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1. Shard Calculation

Query:

Response:

Calculated Shard: 169 (from laksa005)

2. Crawled Status Check

Query:

curl -X POST \
  'http://laksa169.int.ahrefs:8124/' \
  -H 'Content-Type: text/plain' \
  -H 'X-ClickHouse-Database: crawler3' \
  -H 'Authorization: Basic YXBpOg==' \
  -d 'SELECT getAhrefsURLFromUnparsed(src_unparsed) AS found_url, ifNull(toUnixTimestamp(download_stamp), 0) AS crawl_time, ifNull(toUnixTimestamp(props_url_first_seen), 0) AS first_indexed_time, download_http_code AS http_code, src_unparsed AS src_unparsed, src_root_hash AS src_root_hash, history_drop_reason AS history_drop_reason, meta_title AS meta_title, meta_descriptions AS meta_descriptions, attrs_boilerpipe_text AS attrs_boilerpipe_text, attrs_markdown AS attrs_markdown, attrs_readable_markdown AS attrs_readable_markdown, meta_canonical AS meta_canonical FROM crawler3.page_info_local FINAL PREWHERE (src_root_hash, src_unparsed) IN ((getAhrefsRootHashFromUnparsed(getAhrefsUnparsedNoserviceFromURL(\'https://stackoverflow.com/questions/1279542/how-to-execute-a-java-class-from-the-command-line\')), getAhrefsUnparsedNoserviceFromURL(\'https://stackoverflow.com/questions/1279542/how-to-execute-a-java-class-from-the-command-line\'))) FORMAT JSONEachRow'

Response:

{"found_url":"https:\/\/stackoverflow.com\/questions\/1279542\/how-to-execute-a-java-class-from-the-command-line","crawl_time":1774769186,"first_indexed_time":1495651248,"http_code":200,"src_unparsed":"com,stackoverflow!\/questions\/1279542\/how-to-execute-a-java-class-from-the-command-line s443","src_root_hash":"714406497480128969","history_drop_reason":null,"meta_title":"How to execute a java .class from the command line - Stack Overflow","meta_descriptions":[],"attrs_boilerpipe_text":"This question shows research effort; it is useful and clear\n146\nSave this question.\nShow activity on this post.\nI have a compiled java class:\nEcho.class\npublic\nclass\nEcho\n{\npublic\nstatic\nvoid\nmain\n(String arg)\n{\n\n            System.out.println(arg);\n    }\n}\nI\ncd\nto the directory and enter:\njava Echo \"hello\"\nI get this error:\nC:\\Documents and Settings\\joe\\My Documents\\projects\\Misc\\bin>java Echo\n\"hello\"\nException in thread\n\"main\"\njava.lang.NoClassDefFoundError: Echo\nCaused by: java.lang.ClassNotFoundException: Echo\n        at java.net.URLClassLoader$\n1.\nrun(Unknown Source)\n        at java.security.AccessController.doPrivileged(Native Method)\n        at java.net.URLClassLoader.findClass(Unknown Source)\n        at java.lang.ClassLoader.loadClass(Unknown Source)\n        at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)\n        at java.lang.ClassLoader.loadClass(Unknown Source)\n        at java.lang.ClassLoader.loadClassInternal(Unknown Source)\nCould not find the main class: Echo.  Program will exit.\nWhat is the simplest way to get my java code in a form that I can run from the command line as apposed to having to use Eclipse IDE?\nMel\n6,105\n10 gold badges\n40 silver badges\n42 bronze badges\nasked\nAug 14, 2009 at 18:52\n1\nThis answer is useful\n144\nSave this answer.\nShow activity on this post.\nTry:\njava -cp . Echo\n\"hello\"\nAssuming that you compiled with:\njavac Echo.java\nThen there is a chance that the \"current\" directory is not in your classpath ( where java looks for .class definitions )\nIf that's the case and listing the contents of your dir displays:\nEcho.java\nEcho.class\nThen any of this may work:\njava -cp . Echo\n\"hello\"\nor\nSET CLASSPATH=%CLASSPATH;.  \n\njava Echo\n\"hello\"\nAnd later as\nFredrik\npoints out you'll get another error message like.\nException in thread \"main\" java.lang.NoSuchMethodError: main\nWhen that happens, go and read his answer :)\nanswered\nAug 14, 2009 at 18:53\n1 Comment\nThe -cp . to tell Java that he should add . (current working directory) to the classpath, meaning the place where he is looking for code.\n2009-08-14T19:24:39.143Z+00:00\nThis answer is useful\n53\nSave this answer.\nShow activity on this post.\nWith Java 11 you won't have to go through this rigmarole anymore!\nInstead, you can do this:\n> java MyApp.java\nYou don't have to compile beforehand, as it's all done in one step.\nYou can get the Java 11 JDK here:\nJDK 11 GA Release\nanswered\nOct 4, 2018 at 6:12\nRyan Lundy\n211k\n41 gold badges\n187 silver badges\n216 bronze badges\n1 Comment\n> copy C:\\Desenv\\workspaceServer\\TestProject\\src\\WebServiceStandAlone\\MyApp.java . \/y && javac MyApp.java && java -cp . MyApp && del MyApp.class && del MyApp.java  Some guys do prefer the old fashion way =)\n2018-11-13T20:15:04.063Z+00:00\nThis answer is useful\n21\nSave this answer.\nShow activity on this post.\nYou need to specify the classpath. This should do it:\njava -cp . Echo\n\"hello\"\nThis tells java to use\n.\n(the current directory) as its classpath, i.e. the place where it looks for classes. Note than when you use packages, the classpath has to contain the root directory, not the package subdirectories. e.g. if your class is\nmy.package.Echo\nand the .class file is\nbin\/my\/package\/Echo.class\n, the correct classpath directory is\nbin\n.\nanswered\nAug 14, 2009 at 18:54\nComments\nThis answer is useful\n21\nSave this answer.\nShow activity on this post.\nYou have no valid main method... The signature should be:\npublic static void main(\nString[]\nargs);\nHence, in your case the code should look like this:\npublic\nclass\nEcho\n{\npublic\nstatic\nvoid\nmain\n(String[] arg)\n{\n\n            System.out.println(arg[\n0\n]);\n    }\n}\nEdit:\nPlease note that\nOscar\nis also right in that you are missing . in your classpath, you would run into the problem I solve after you have dealt with that error.\nanswered\nAug 14, 2009 at 18:54\nFredrik\n5,859\n2 gold badges\n29 silver badges\n33 bronze badges\n2 Comments\nThe only one to give the right result with newer java's.\n2023-09-03T12:42:17.977Z+00:00\nKeep in mind this thread dates back to 2009 :-)\n2023-09-08T07:30:46.43Z+00:00\nThis answer is useful\n8\nSave this answer.\nShow activity on this post.\nIf you have in your java source\npackage\nmypackage;\nand your class is hello.java\nwith\npublic\nclass\nhello\n{\nand in that hello.java you have\npublic\nstatic\nvoid\nmain\n(String[] args)\n{\nThen\n(after compilation) \nchangeDir (cd) to the directory where your hello.class is. \nThen\njava -cp . mypackage.hello\nMind the current directory and the package name before the class name.\nIt works for my on linux mint and i hope on the other  os's also\nThanks Stack overflow for a wealth of info.\nanswered\nMar 17, 2018 at 8:22\n1 Comment\nThis answer is useful\n3\nSave this answer.\nShow activity on this post.\nMy situation was a little complicated.  I had to do three steps since I was using a .dll in the resources directory, for JNI code.  My files were\nS:\\Accessibility\\tools\\src\\main\\resources\\dlls\\HelloWorld.dll\nS:\\Accessibility\\tools\\src\\test\\java\\com\\accessibility\\HelloWorld.class\nMy code contained the following line\nSystem.load(HelloWorld.class.getResource(\n\"\/dlls\/HelloWorld.dll\"\n).getPath());\nFirst, I had to move to the classpath directory\ncd \/D\n\"S:\\Accessibility\\tools\\src\\test\\java\"\nNext, I had to change the classpath to point to the current directory so that my class would be loaded and I had to change the classpath to point to he resources directory so my dll would be loaded.\nset classpath=%classpath%;.;..\\..\\..\\src\\main\\resources;\nThen, I had to run java using the classname.\njava com.accessibility.HelloWorld\nanswered\nAug 10, 2013 at 1:30\nScott Izu\n2,319\n25 silver badges\n14 bronze badges\nComments\nThis answer is useful\n0\nSave this answer.\nShow activity on this post.\nFirst, have you compiled the class using the command line javac compiler?  Second, it seems that your main method has an incorrect signature - it should be taking in an array of String objects, rather than just one:\npublic\nstatic\nvoid\nmain\n(String[] args)\n{\nOnce you've changed your code to take in an array of String objects, then you need to make sure that you're printing an element of the array, rather than array itself:\nSystem.out.println(args[\n0\n])\nIf you want to print the whole list of command line arguments, you'd need to use a loop, e.g.\nfor\n(\nint\ni\n=\n0\n; i < args.length; i++){\n    System.out.print(args[i]);\n}\nSystem.out.println();\nanswered\nAug 14, 2009 at 19:03\nquanticle\n5,070\n6 gold badges\n35 silver badges\n42 bronze badges\nComments\nStart asking to get answers\nFind the answer to your question by asking.\nAsk question\nExplore related questions\nSee similar questions with these tags.","attrs_markdown":"# ![site logo](https:\/\/stackoverflow.com\/Content\/Img\/SE-logo75.png)\nBy clicking “Sign up”, you agree to our [terms of service](https:\/\/stackoverflow.com\/legal\/terms-of-service\/public) and acknowledge you have read our [privacy policy](https:\/\/stackoverflow.com\/legal\/privacy-policy).\n\n# OR\n\nAlready have an account? 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Bring the best of human thought and AI automation together at your work.\n   \n   [Try for free](https:\/\/stackoverflowteams.com\/teams\/create\/free\/?utm_medium=referral&utm_source=stackoverflow-community&utm_campaign=side-bar&utm_content=explore-teams) [Learn more](https:\/\/stackoverflow.co\/internal\/?utm_medium=referral&utm_source=stackoverflow-community&utm_campaign=side-bar&utm_content=explore-teams)\n3. [Stack Internal]()\n4. Bring the best of human thought and AI automation together at your work. [Learn more](https:\/\/stackoverflow.co\/internal\/?utm_medium=referral&utm_source=stackoverflow-community&utm_campaign=side-bar&utm_content=explore-teams-compact)\n\n##### Collectives™ on Stack Overflow\nFind centralized, trusted content and collaborate around the technologies you use most.\n\n[Learn more about Collectives](https:\/\/stackoverflow.com\/collectives)\n\n**Stack Internal**\n\nKnowledge at work\n\nBring the best of human thought and AI automation together at your work.\n\n[Explore Stack Internal](https:\/\/stackoverflow.co\/internal\/?utm_medium=referral&utm_source=stackoverflow-community&utm_campaign=side-bar&utm_content=explore-teams-compact-popover)\n\n# [How to execute a java .class from the command line](https:\/\/stackoverflow.com\/questions\/1279542\/how-to-execute-a-java-class-from-the-command-line)\n[Ask Question](https:\/\/stackoverflow.com\/questions\/ask)\n\nAsked\n\n16 years, 7 months ago\n\nModified [3 years, 8 months ago](https:\/\/stackoverflow.com\/questions\/1279542\/how-to-execute-a-java-class-from-the-command-line?lastactivity \"2022-06-18 04:27:08Z\")\n\nViewed 529k times\n\nThis question shows research effort; it is useful and clear\n\n146\n\nSave this question.\n\nShow activity on this post.\n\nI have a compiled java class:\n\n**Echo.class**\n```\nCopy\n```\nI `cd` to the directory and enter: `java Echo \"hello\"`\n\nI get this error:\n```\nCopy\n```\nWhat is the simplest way to get my java code in a form that I can run from the command line as apposed to having to use Eclipse IDE?\n\n- [java](https:\/\/stackoverflow.com\/questions\/tagged\/java \"show questions tagged 'java'\")\n\n[Share](https:\/\/stackoverflow.com\/q\/1279542 \"Short permalink to this question\")\n\nShare a link to this question\n\nCopy link\n\n[CC BY-SA 3.0](https:\/\/creativecommons.org\/licenses\/by-sa\/3.0\/ \"The current license for this post: CC BY-SA 3.0\")\n\n[Improve this question](https:\/\/stackoverflow.com\/posts\/1279542\/edit)\n\nFollow\n\nFollow this question to receive notifications\n\n[edited Apr 27, 2017 at 10:38](https:\/\/stackoverflow.com\/posts\/1279542\/revisions \"show all edits to this post\")\n\n[![Mel's user avatar](https:\/\/i.sstatic.net\/c8sPO.png?s=64)](https:\/\/stackoverflow.com\/users\/4720935\/mel)\n\n[Mel](https:\/\/stackoverflow.com\/users\/4720935\/mel)\n\n6,1051010 gold badges4040 silver badges4242 bronze badges\n\nasked Aug 14, 2009 at 18:52\n\n[![joe's user avatar](https:\/\/www.gravatar.com\/avatar\/aa22bf0ceed78fdc4f3753d5d24c80de?s=64&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/5653\/joe)\n\n[joe](https:\/\/stackoverflow.com\/users\/5653\/joe)\n\n17\\.6k3737 gold badges9999 silver badges134134 bronze badges\n\n1\n\n- 22\n  Suggestion: The original question would, perhaps, better be left unedited in order not to invalidate the answers, under a quick review. Really weird to see the right method signature and then a bunch of answers that say it was incorrect. Erroneous code is supposed to be left that, for the purpose of comparison with the correct version, at least.\n  \n  JSmyth\n  \n  – [JSmyth](https:\/\/stackoverflow.com\/users\/588966\/jsmyth \"1,504 reputation\")\n  \n  2014-02-03 09:34:18 +00:00\n  \n  [Commented Feb 3, 2014 at 9:34](https:\/\/stackoverflow.com\/questions\/1279542\/how-to-execute-a-java-class-from-the-command-line#comment32497877_1279542)\n\n[Add a comment](https:\/\/stackoverflow.com\/questions\/1279542\/how-to-execute-a-java-class-from-the-command-line \"Use comments to ask for more information or suggest improvements. Avoid answering questions in comments.\")   \\|\n\n## 7 Answers 7\nSorted by:\n\n[Reset to default](https:\/\/stackoverflow.com\/questions\/1279542\/how-to-execute-a-java-class-from-the-command-line?answertab=scoredesc#tab-top)\n\nThis answer is useful\n\n144\n\nSave this answer.\n\nShow activity on this post.\n\nTry:\n```\nCopyjava -cp . Echo \"hello\"\n```\n***\nAssuming that you compiled with:\n```\nCopyjavac Echo.java\n```\nThen there is a chance that the \"current\" directory is not in your classpath ( where java looks for .class definitions )\n\nIf that's the case and listing the contents of your dir displays:\n```\nCopy\n```\nThen any of this may work:\n```\nCopyjava -cp . Echo \"hello\"\n```\nor\n```\nCopy\n```\nAnd later as [Fredrik](https:\/\/stackoverflow.com\/questions\/1279542\/how-to-execute-a-java-class-from-the-command-line\/1279560#1279560) points out you'll get another error message like.\n\n> *Exception in thread \"main\" java.lang.NoSuchMethodError: main*\n\nWhen that happens, go and read his answer :)\n\n[Share](https:\/\/stackoverflow.com\/a\/1279556 \"Short permalink to this answer\")\n\nShare a link to this answer\n\nCopy link\n\n[CC BY-SA 2.5](https:\/\/creativecommons.org\/licenses\/by-sa\/2.5\/ \"The current license for this post: CC BY-SA 2.5\")\n\n[Improve this answer](https:\/\/stackoverflow.com\/posts\/1279556\/edit)\n\nFollow\n\nFollow this answer to receive notifications\n\n[edited May 23, 2017 at 10:31](https:\/\/stackoverflow.com\/posts\/1279556\/revisions \"show all edits to this post\")\n\n[![Community's user avatar](https:\/\/www.gravatar.com\/avatar\/a007be5a61f6aa8f3e85ae2fc18dd66e?s=64&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/-1\/community)\n\n[Community](https:\/\/stackoverflow.com\/users\/-1\/community)Bot\n\n111 silver badge\n\nanswered Aug 14, 2009 at 18:53\n\n[![OscarRyz's user avatar](https:\/\/www.gravatar.com\/avatar\/94066dfa49c2feb14706cb081848fda7?s=64&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/20654\/oscarryz)\n\n[OscarRyz](https:\/\/stackoverflow.com\/users\/20654\/oscarryz)\n\n200k119119 gold badges399399 silver badges577577 bronze badges\n\nSign up to request clarification or add additional context in comments.\n\n## 1 Comment\nAdd a comment\n\n[![](https:\/\/www.gravatar.com\/avatar\/826f4d6edd2e93e07aacd04bf07da069?s=48&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/59572\/fredrik)\n\nFredrik\n\n[Fredrik](https:\/\/stackoverflow.com\/users\/59572\/fredrik)\n\n[Over a year ago](https:\/\/stackoverflow.com\/questions\/1279542\/how-to-execute-a-java-class-from-the-command-line#comment1108622_1279556)\n\nThe -cp . to tell Java that he should add . (current working directory) to the classpath, meaning the place where he is looking for code.\n\n2009-08-14T19:24:39.143Z+00:00\n\n3\n\nReply\n\n- Copy link\n\nThis answer is useful\n\n53\n\nSave this answer.\n\nShow activity on this post.\n\nWith Java 11 you won't have to go through this rigmarole anymore\\!\n\nInstead, you can do this:\n```\nCopy> java MyApp.java\n```\nYou don't have to compile beforehand, as it's all done in one step.\n\nYou can get the Java 11 JDK here: [JDK 11 GA Release](https:\/\/jdk.java.net\/11\/)\n\n[Share](https:\/\/stackoverflow.com\/a\/52640128 \"Short permalink to this answer\")\n\nShare a link to this answer\n\nCopy link\n\n[CC BY-SA 4.0](https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/ \"The current license for this post: CC BY-SA 4.0\")\n\n[Improve this answer](https:\/\/stackoverflow.com\/posts\/52640128\/edit)\n\nFollow\n\nFollow this answer to receive notifications\n\nanswered Oct 4, 2018 at 6:12\n\n[![Ryan Lundy's user avatar](https:\/\/www.gravatar.com\/avatar\/750159e9cdab58c4b6547d382311c9af?s=64&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/5486\/ryan-lundy)\n\n[Ryan Lundy](https:\/\/stackoverflow.com\/users\/5486\/ryan-lundy)\n\n211k4141 gold badges187187 silver badges216216 bronze badges\n\n## 1 Comment\nAdd a comment\n\n[![](https:\/\/i.sstatic.net\/1O0b6.jpg?s=64)](https:\/\/stackoverflow.com\/users\/929263\/jr)\n\nJr.\n\n[Jr.](https:\/\/stackoverflow.com\/users\/929263\/jr)\n\n[Over a year ago](https:\/\/stackoverflow.com\/questions\/1279542\/how-to-execute-a-java-class-from-the-command-line#comment93459597_52640128)\n\n\\> copy C:\\\\Desenv\\\\workspaceServer\\\\TestProject\\\\src\\\\WebServiceStandAlone\\\\MyApp.java . \/y && javac MyApp.java && java -cp . MyApp && del MyApp.class && del MyApp.java Some guys do prefer the old fashion way =)\n\n2018-11-13T20:15:04.063Z+00:00\n\n0\n\nReply\n\n- Copy link\n\nThis answer is useful\n\n21\n\nSave this answer.\n\nShow activity on this post.\n\nYou need to specify the classpath. This should do it:\n```\nCopyjava -cp . Echo \"hello\"\n```\nThis tells java to use `.` (the current directory) as its classpath, i.e. the place where it looks for classes. Note than when you use packages, the classpath has to contain the root directory, not the package subdirectories. e.g. if your class is `my.package.Echo` and the .class file is `bin\/my\/package\/Echo.class`, the correct classpath directory is `bin`.\n\n[Share](https:\/\/stackoverflow.com\/a\/1279559 \"Short permalink to this answer\")\n\nShare a link to this answer\n\nCopy link\n\n[CC BY-SA 2.5](https:\/\/creativecommons.org\/licenses\/by-sa\/2.5\/ \"The current license for this post: CC BY-SA 2.5\")\n\n[Improve this answer](https:\/\/stackoverflow.com\/posts\/1279559\/edit)\n\nFollow\n\nFollow this answer to receive notifications\n\nanswered Aug 14, 2009 at 18:54\n\n[![Michael Borgwardt's user avatar](https:\/\/www.gravatar.com\/avatar\/0382297f273df0a544b0c6c2734de096?s=64&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/16883\/michael-borgwardt)\n\n[Michael Borgwardt](https:\/\/stackoverflow.com\/users\/16883\/michael-borgwardt)\n\n347k8181 gold badges491491 silver badges726726 bronze badges\n\n## Comments\nAdd a comment\n\nThis answer is useful\n\n21\n\nSave this answer.\n\nShow activity on this post.\n\nYou have no valid main method... The signature should be: public static void main(**String\\[\\]** args);\n\nHence, in your case the code should look like this:\n```\nCopy\n```\n**Edit:** Please note that [Oscar](https:\/\/stackoverflow.com\/questions\/1279542\/how-to-execute-a-java-class-from-the-command-line\/1279556#1279556) is also right in that you are missing . in your classpath, you would run into the problem I solve after you have dealt with that error.\n\n[Share](https:\/\/stackoverflow.com\/a\/1279560 \"Short permalink to this answer\")\n\nShare a link to this answer\n\nCopy link\n\n[CC BY-SA 3.0](https:\/\/creativecommons.org\/licenses\/by-sa\/3.0\/ \"The current license for this post: CC BY-SA 3.0\")\n\n[Improve this answer](https:\/\/stackoverflow.com\/posts\/1279560\/edit)\n\nFollow\n\nFollow this answer to receive notifications\n\n[edited May 23, 2017 at 12:02](https:\/\/stackoverflow.com\/posts\/1279560\/revisions \"show all edits to this post\")\n\n[![Community's user avatar](https:\/\/www.gravatar.com\/avatar\/a007be5a61f6aa8f3e85ae2fc18dd66e?s=64&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/-1\/community)\n\n[Community](https:\/\/stackoverflow.com\/users\/-1\/community)Bot\n\n111 silver badge\n\nanswered Aug 14, 2009 at 18:54\n\n[![Fredrik's user avatar](https:\/\/www.gravatar.com\/avatar\/826f4d6edd2e93e07aacd04bf07da069?s=64&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/59572\/fredrik)\n\n[Fredrik](https:\/\/stackoverflow.com\/users\/59572\/fredrik)\n\n5,85922 gold badges2929 silver badges3333 bronze badges\n\n## 2 Comments\nAdd a comment\n\n[![](https:\/\/www.gravatar.com\/avatar\/481b12c3fecaf223af0522000fbcb531?s=48&d=identicon&r=PG&f=y&so-version=2)](https:\/\/stackoverflow.com\/users\/4952917\/erich-k%C3%BCster)\n\nErich Küster\n\n[Erich Küster](https:\/\/stackoverflow.com\/users\/4952917\/erich-k%C3%BCster)\n\n[Over a year ago](https:\/\/stackoverflow.com\/questions\/1279542\/how-to-execute-a-java-class-from-the-command-line#comment135798271_1279560)\n\nThe only one to give the right result with newer java's.\n\n2023-09-03T12:42:17.977Z+00:00\n\n0\n\nReply\n\n- Copy link\n\n[![](https:\/\/www.gravatar.com\/avatar\/826f4d6edd2e93e07aacd04bf07da069?s=48&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/59572\/fredrik)\n\nFredrik\n\n[Fredrik](https:\/\/stackoverflow.com\/users\/59572\/fredrik)\n\n[Over a year ago](https:\/\/stackoverflow.com\/questions\/1279542\/how-to-execute-a-java-class-from-the-command-line#comment135857198_1279560)\n\nKeep in mind this thread dates back to 2009 :-)\n\n2023-09-08T07:30:46.43Z+00:00\n\n0\n\nReply\n\n- Copy link\n\nThis answer is useful\n\n8\n\nSave this answer.\n\nShow activity on this post.\n\nIf you have in your java source\n```\nCopypackage mypackage;\n```\nand your class is hello.java with\n```\nCopypublic class hello {\n```\nand in that hello.java you have\n```\nCopy public static void main(String[] args) {\n```\nThen (after compilation) changeDir (cd) to the directory where your hello.class is. Then\n```\nCopyjava -cp . mypackage.hello\n```\nMind the current directory and the package name before the class name. It works for my on linux mint and i hope on the other os's also\n\nThanks Stack overflow for a wealth of info.\n\n[Share](https:\/\/stackoverflow.com\/a\/49333968 \"Short permalink to this answer\")\n\nShare a link to this answer\n\nCopy link\n\n[CC BY-SA 3.0](https:\/\/creativecommons.org\/licenses\/by-sa\/3.0\/ \"The current license for this post: CC BY-SA 3.0\")\n\n[Improve this answer](https:\/\/stackoverflow.com\/posts\/49333968\/edit)\n\nFollow\n\nFollow this answer to receive notifications\n\nanswered Mar 17, 2018 at 8:22\n\n[![Gerard Doets's user avatar](https:\/\/www.gravatar.com\/avatar\/835cd24768924bfe5ec75bae4c72ad4e?s=64&d=identicon&r=PG&f=y&so-version=2)](https:\/\/stackoverflow.com\/users\/8344297\/gerard-doets)\n\n[Gerard Doets](https:\/\/stackoverflow.com\/users\/8344297\/gerard-doets)\n\n8111 silver badge22 bronze badges\n\n## 1 Comment\nAdd a comment\n\n[![](https:\/\/www.gravatar.com\/avatar\/600a453e63e5e8d9f735e91cdc5cb839?s=48&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/1300170\/ruvim)\n\nruvim\n\n[ruvim](https:\/\/stackoverflow.com\/users\/1300170\/ruvim)\n\n[Over a year ago](https:\/\/stackoverflow.com\/questions\/1279542\/how-to-execute-a-java-class-from-the-command-line#comment87017442_49333968)\n\nNB: the class file should be foundable via `.\/mypackage\/hello.class` name. See also: \"[Running java in package from command line](https:\/\/stackoverflow.com\/questions\/19433366\/running-java-in-package-from-command-line)\" question.\n\n2018-04-24T11:40:03.46Z+00:00\n\n3\n\nReply\n\n- Copy link\n\nThis answer is useful\n\n3\n\nSave this answer.\n\nShow activity on this post.\n\nMy situation was a little complicated. I had to do three steps since I was using a .dll in the resources directory, for JNI code. My files were\n```\nCopy\n```\nMy code contained the following line\n```\nCopySystem.load(HelloWorld.class.getResource(\"\/dlls\/HelloWorld.dll\").getPath());\n```\nFirst, I had to move to the classpath directory\n```\nCopycd \/D \"S:\\Accessibility\\tools\\src\\test\\java\"\n```\nNext, I had to change the classpath to point to the current directory so that my class would be loaded and I had to change the classpath to point to he resources directory so my dll would be loaded.\n```\nCopyset classpath=%classpath%;.;..\\..\\..\\src\\main\\resources;\n```\nThen, I had to run java using the classname.\n```\nCopyjava com.accessibility.HelloWorld\n```\n\n[Share](https:\/\/stackoverflow.com\/a\/18157831 \"Short permalink to this answer\")\n\nShare a link to this answer\n\nCopy link\n\n[CC BY-SA 3.0](https:\/\/creativecommons.org\/licenses\/by-sa\/3.0\/ \"The current license for this post: CC BY-SA 3.0\")\n\n[Improve this answer](https:\/\/stackoverflow.com\/posts\/18157831\/edit)\n\nFollow\n\nFollow this answer to receive notifications\n\nanswered Aug 10, 2013 at 1:30\n\n[![Scott Izu's user avatar](https:\/\/www.gravatar.com\/avatar\/da28e044b5207cc1dff86a86cb31432d?s=64&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/2663340\/scott-izu)\n\n[Scott Izu](https:\/\/stackoverflow.com\/users\/2663340\/scott-izu)\n\n2,3192525 silver badges1414 bronze badges\n\n## Comments\nAdd a comment\n\nThis answer is useful\n\n0\n\nSave this answer.\n\nShow activity on this post.\n\nFirst, have you compiled the class using the command line javac compiler? Second, it seems that your main method has an incorrect signature - it should be taking in an array of String objects, rather than just one:\n```\nCopypublic static void main(String[] args){\n```\nOnce you've changed your code to take in an array of String objects, then you need to make sure that you're printing an element of the array, rather than array itself:\n```\nCopySystem.out.println(args[0])\n```\nIf you want to print the whole list of command line arguments, you'd need to use a loop, e.g.\n```\nCopy\n```\n\n[Share](https:\/\/stackoverflow.com\/a\/1279608 \"Short permalink to this answer\")\n\nShare a link to this answer\n\nCopy link\n\n[CC BY-SA 2.5](https:\/\/creativecommons.org\/licenses\/by-sa\/2.5\/ \"The current license for this post: CC BY-SA 2.5\")\n\n[Improve this answer](https:\/\/stackoverflow.com\/posts\/1279608\/edit)\n\nFollow\n\nFollow this answer to receive notifications\n\nanswered Aug 14, 2009 at 19:03\n\n[![quanticle's user avatar](https:\/\/www.gravatar.com\/avatar\/31fa94a51ce1eb3edd1fefbfcd684484?s=64&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/149125\/quanticle)\n\n[quanticle](https:\/\/stackoverflow.com\/users\/149125\/quanticle)\n\n5,07066 gold badges3535 silver badges4242 bronze badges\n\n## Comments\nAdd a comment\n\nStart asking to get answers\n\nFind the answer to your question by asking.\n\n[Ask question](https:\/\/stackoverflow.com\/questions\/ask)\n\nExplore related questions\n\n- [java](https:\/\/stackoverflow.com\/questions\/tagged\/java \"show questions tagged 'java'\")\n\nSee similar questions with these tags.\n\n- The Overflow Blog\n- [DeveloperWeek 2026: Making AI tools that are actually good](https:\/\/stackoverflow.blog\/2026\/03\/05\/developerweek-2026\/?cb=1)\n- [Building brains for bulldozers](https:\/\/stackoverflow.blog\/2026\/03\/06\/building-brains-for-bulldozers\/?cb=1)\n- Featured on Meta\n- [Logo updates to Stack Overflow's visual identity](https:\/\/meta.stackexchange.com\/questions\/417394\/logo-updates-to-stack-overflows-visual-identity?cb=1)\n- [Policy: Generative AI (e.g., ChatGPT) is banned](https:\/\/meta.stackoverflow.com\/questions\/421831\/policy-generative-ai-e-g-chatgpt-is-banned?cb=1)\n- [New site design and philosophy for Stack Overflow: Starting February 24, 2026...](https:\/\/meta.stackoverflow.com\/questions\/438177\/new-site-design-and-philosophy-for-stack-overflow-starting-february-24-2026-at?cb=1 \"New site design and philosophy for Stack Overflow: Starting February 24, 2026 at beta.stackoverflow.com\")\n- [I’m Jody, the Chief Product and Technology Officer at Stack Overflow. 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[What's reputation and how do I get it?](https:\/\/stackoverflow.com\/help\/whats-reputation)\n\nInstead, you can save this post to reference later.\n\nSave this post for later\n\nNot now\n\n##### [Stack Overflow](https:\/\/stackoverflow.com\/)\n- [Questions](https:\/\/stackoverflow.com\/questions)\n- [Help](https:\/\/stackoverflow.com\/help)\n- [Chat](https:\/\/chat.stackoverflow.com\/?tab=explore)\n\n##### [Business](https:\/\/stackoverflow.co\/)\n- [Stack Internal](https:\/\/stackoverflow.co\/internal\/?utm_medium=referral&utm_source=stackoverflow-community&utm_campaign=footer&utm_content=teams)\n- [Stack Data Licensing](https:\/\/stackoverflow.co\/data-licensing\/?utm_medium=referral&utm_source=stackoverflow-community&utm_campaign=footer&utm_content=data-licensing)\n- [Stack Ads](https:\/\/stackoverflow.co\/advertising\/?utm_medium=referral&utm_source=stackoverflow-community&utm_campaign=footer&utm_content=advertising)\n\n##### [Company](https:\/\/stackoverflow.co\/)\n- [About](https:\/\/stackoverflow.co\/)\n- [Press](https:\/\/stackoverflow.co\/company\/press\/)\n- [Work Here](https:\/\/stackoverflow.co\/company\/work-here\/)\n- [Legal](https:\/\/stackoverflow.com\/legal)\n- [Privacy Policy](https:\/\/stackoverflow.com\/legal\/privacy-policy)\n- [Terms of Service](https:\/\/stackoverflow.com\/legal\/terms-of-service\/public)\n- [Contact Us](https:\/\/stackoverflow.com\/contact)\n- Cookie Settings\n- [Cookie Policy](https:\/\/policies.stackoverflow.co\/stack-overflow\/cookie-policy)\n\n##### [Stack Exchange Network](https:\/\/stackexchange.com\/)\n- [Technology](https:\/\/stackexchange.com\/sites#technology)\n- [Culture & recreation](https:\/\/stackexchange.com\/sites#culturerecreation)\n- [Life & arts](https:\/\/stackexchange.com\/sites#lifearts)\n- [Science](https:\/\/stackexchange.com\/sites#science)\n- [Professional](https:\/\/stackexchange.com\/sites#professional)\n- [Business](https:\/\/stackexchange.com\/sites#business)\n- [API](https:\/\/api.stackexchange.com\/)\n- [Data](https:\/\/data.stackexchange.com\/)\n\n- [Blog](https:\/\/stackoverflow.blog\/?blb=1)\n- [Facebook](https:\/\/www.facebook.com\/officialstackoverflow\/)\n- [Twitter](https:\/\/twitter.com\/stackoverflow)\n- [LinkedIn](https:\/\/linkedin.com\/company\/stack-overflow)\n- [Instagram](https:\/\/www.instagram.com\/thestackoverflow)\n\nSite design \/ logo © 2026 Stack Exchange Inc;  user contributions licensed under  [CC BY-SA](https:\/\/stackoverflow.com\/help\/licensing) .  rev 2026.3.6.40623","attrs_readable_markdown":"This question shows research effort; it is useful and clear\n\n146\n\nSave this question.\n\nShow activity on this post.\n\nI have a compiled java class:\n\n**Echo.class**\n```\npublic class Echo {\n    public static void main (String arg) {\n\n            System.out.println(arg);\n    }\n}\n```\nI `cd` to the directory and enter: `java Echo \"hello\"`\n\nI get this error:\n```\nC:\\Documents and Settings\\joe\\My Documents\\projects\\Misc\\bin>java Echo \"hello\"\nException in thread \"main\" java.lang.NoClassDefFoundError: Echo\nCaused by: java.lang.ClassNotFoundException: Echo\n        at java.net.URLClassLoader$1.run(Unknown Source)\n        at java.security.AccessController.doPrivileged(Native Method)\n        at java.net.URLClassLoader.findClass(Unknown Source)\n        at java.lang.ClassLoader.loadClass(Unknown Source)\n        at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)\n        at java.lang.ClassLoader.loadClass(Unknown Source)\n        at java.lang.ClassLoader.loadClassInternal(Unknown Source)\nCould not find the main class: Echo.  Program will exit.\n```\nWhat is the simplest way to get my java code in a form that I can run from the command line as apposed to having to use Eclipse IDE?\n\n[![Mel's user avatar](https:\/\/i.sstatic.net\/c8sPO.png?s=64)](https:\/\/stackoverflow.com\/users\/4720935\/mel)\n\n[Mel](https:\/\/stackoverflow.com\/users\/4720935\/mel)\n\n6,10510 gold badges40 silver badges42 bronze badges\n\nasked Aug 14, 2009 at 18:52\n\n[![joe's user avatar](https:\/\/www.gravatar.com\/avatar\/aa22bf0ceed78fdc4f3753d5d24c80de?s=64&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/5653\/joe)\n\n1\n\nThis answer is useful\n\n144\n\nSave this answer.\n\nShow activity on this post.\n\nTry:\n```\njava -cp . Echo \"hello\"\n```\n***\nAssuming that you compiled with:\n```\njavac Echo.java\n```\nThen there is a chance that the \"current\" directory is not in your classpath ( where java looks for .class definitions )\n\nIf that's the case and listing the contents of your dir displays:\n```\nEcho.java\nEcho.class\n```\nThen any of this may work:\n```\njava -cp . Echo \"hello\"\n```\nor\n```\nSET CLASSPATH=%CLASSPATH;.  \n\njava Echo \"hello\"\n```\nAnd later as [Fredrik](https:\/\/stackoverflow.com\/questions\/1279542\/how-to-execute-a-java-class-from-the-command-line\/1279560#1279560) points out you'll get another error message like.\n\n> *Exception in thread \"main\" java.lang.NoSuchMethodError: main*\n\nWhen that happens, go and read his answer :)\n\n[![Community's user avatar](https:\/\/www.gravatar.com\/avatar\/a007be5a61f6aa8f3e85ae2fc18dd66e?s=64&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/-1\/community)\n\nanswered Aug 14, 2009 at 18:53\n\n[![OscarRyz's user avatar](https:\/\/www.gravatar.com\/avatar\/94066dfa49c2feb14706cb081848fda7?s=64&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/20654\/oscarryz)\n\n1 Comment\n\n[![](https:\/\/www.gravatar.com\/avatar\/826f4d6edd2e93e07aacd04bf07da069?s=48&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/59572\/fredrik)\n\nThe -cp . to tell Java that he should add . (current working directory) to the classpath, meaning the place where he is looking for code.\n\n2009-08-14T19:24:39.143Z+00:00\n\nThis answer is useful\n\n53\n\nSave this answer.\n\nShow activity on this post.\n\nWith Java 11 you won't have to go through this rigmarole anymore\\!\n\nInstead, you can do this:\n```\n> java MyApp.java\n```\nYou don't have to compile beforehand, as it's all done in one step.\n\nYou can get the Java 11 JDK here: [JDK 11 GA Release](https:\/\/jdk.java.net\/11\/)\n\nanswered Oct 4, 2018 at 6:12\n\n[![Ryan Lundy's user avatar](https:\/\/www.gravatar.com\/avatar\/750159e9cdab58c4b6547d382311c9af?s=64&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/5486\/ryan-lundy)\n\n[Ryan Lundy](https:\/\/stackoverflow.com\/users\/5486\/ryan-lundy)\n\n211k41 gold badges187 silver badges216 bronze badges\n\n1 Comment\n\n[![](https:\/\/i.sstatic.net\/1O0b6.jpg?s=64)](https:\/\/stackoverflow.com\/users\/929263\/jr)\n\n\\> copy C:\\\\Desenv\\\\workspaceServer\\\\TestProject\\\\src\\\\WebServiceStandAlone\\\\MyApp.java . \/y && javac MyApp.java && java -cp . MyApp && del MyApp.class && del MyApp.java Some guys do prefer the old fashion way =)\n\n2018-11-13T20:15:04.063Z+00:00\n\nThis answer is useful\n\n21\n\nSave this answer.\n\nShow activity on this post.\n\nYou need to specify the classpath. This should do it:\n```\njava -cp . Echo \"hello\"\n```\nThis tells java to use `.` (the current directory) as its classpath, i.e. the place where it looks for classes. Note than when you use packages, the classpath has to contain the root directory, not the package subdirectories. e.g. if your class is `my.package.Echo` and the .class file is `bin\/my\/package\/Echo.class`, the correct classpath directory is `bin`.\n\nanswered Aug 14, 2009 at 18:54\n\n[![Michael Borgwardt's user avatar](https:\/\/www.gravatar.com\/avatar\/0382297f273df0a544b0c6c2734de096?s=64&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/16883\/michael-borgwardt)\n\nComments\n\nThis answer is useful\n\n21\n\nSave this answer.\n\nShow activity on this post.\n\nYou have no valid main method... The signature should be: public static void main(**String\\[\\]** args);\n\nHence, in your case the code should look like this:\n```\npublic class Echo {\n    public static void main (String[] arg) {\n\n            System.out.println(arg[0]);\n    }\n}\n```\n**Edit:** Please note that [Oscar](https:\/\/stackoverflow.com\/questions\/1279542\/how-to-execute-a-java-class-from-the-command-line\/1279556#1279556) is also right in that you are missing . in your classpath, you would run into the problem I solve after you have dealt with that error.\n\n[![Community's user avatar](https:\/\/www.gravatar.com\/avatar\/a007be5a61f6aa8f3e85ae2fc18dd66e?s=64&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/-1\/community)\n\nanswered Aug 14, 2009 at 18:54\n\n[![Fredrik's user avatar](https:\/\/www.gravatar.com\/avatar\/826f4d6edd2e93e07aacd04bf07da069?s=64&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/59572\/fredrik)\n\n[Fredrik](https:\/\/stackoverflow.com\/users\/59572\/fredrik)\n\n5,8592 gold badges29 silver badges33 bronze badges\n\n2 Comments\n\n[![](https:\/\/www.gravatar.com\/avatar\/481b12c3fecaf223af0522000fbcb531?s=48&d=identicon&r=PG&f=y&so-version=2)](https:\/\/stackoverflow.com\/users\/4952917\/erich-k%C3%BCster)\n\nThe only one to give the right result with newer java's.\n\n2023-09-03T12:42:17.977Z+00:00\n\n[![](https:\/\/www.gravatar.com\/avatar\/826f4d6edd2e93e07aacd04bf07da069?s=48&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/59572\/fredrik)\n\nKeep in mind this thread dates back to 2009 :-)\n\n2023-09-08T07:30:46.43Z+00:00\n\nThis answer is useful\n\n8\n\nSave this answer.\n\nShow activity on this post.\n\nIf you have in your java source\n```\npackage mypackage;\n```\nand your class is hello.java with\n```\npublic class hello {\n```\nand in that hello.java you have\n```\n public static void main(String[] args) {\n```\nThen (after compilation) changeDir (cd) to the directory where your hello.class is. Then\n```\njava -cp . mypackage.hello\n```\nMind the current directory and the package name before the class name. It works for my on linux mint and i hope on the other os's also\n\nThanks Stack overflow for a wealth of info.\n\nanswered Mar 17, 2018 at 8:22\n\n[![Gerard Doets's user avatar](https:\/\/www.gravatar.com\/avatar\/835cd24768924bfe5ec75bae4c72ad4e?s=64&d=identicon&r=PG&f=y&so-version=2)](https:\/\/stackoverflow.com\/users\/8344297\/gerard-doets)\n\n1 Comment\n\n[![](https:\/\/www.gravatar.com\/avatar\/600a453e63e5e8d9f735e91cdc5cb839?s=48&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/1300170\/ruvim)\n\nThis answer is useful\n\n3\n\nSave this answer.\n\nShow activity on this post.\n\nMy situation was a little complicated. I had to do three steps since I was using a .dll in the resources directory, for JNI code. My files were\n```\nS:\\Accessibility\\tools\\src\\main\\resources\\dlls\\HelloWorld.dll\nS:\\Accessibility\\tools\\src\\test\\java\\com\\accessibility\\HelloWorld.class\n```\nMy code contained the following line\n```\nSystem.load(HelloWorld.class.getResource(\"\/dlls\/HelloWorld.dll\").getPath());\n```\nFirst, I had to move to the classpath directory\n```\ncd \/D \"S:\\Accessibility\\tools\\src\\test\\java\"\n```\nNext, I had to change the classpath to point to the current directory so that my class would be loaded and I had to change the classpath to point to he resources directory so my dll would be loaded.\n```\nset classpath=%classpath%;.;..\\..\\..\\src\\main\\resources;\n```\nThen, I had to run java using the classname.\n```\njava com.accessibility.HelloWorld\n```\n\nanswered Aug 10, 2013 at 1:30\n\n[![Scott Izu's user avatar](https:\/\/www.gravatar.com\/avatar\/da28e044b5207cc1dff86a86cb31432d?s=64&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/2663340\/scott-izu)\n\n[Scott Izu](https:\/\/stackoverflow.com\/users\/2663340\/scott-izu)\n\n2,31925 silver badges14 bronze badges\n\nComments\n\nThis answer is useful\n\n0\n\nSave this answer.\n\nShow activity on this post.\n\nFirst, have you compiled the class using the command line javac compiler? Second, it seems that your main method has an incorrect signature - it should be taking in an array of String objects, rather than just one:\n```\npublic static void main(String[] args){\n```\nOnce you've changed your code to take in an array of String objects, then you need to make sure that you're printing an element of the array, rather than array itself:\n```\nSystem.out.println(args[0])\n```\nIf you want to print the whole list of command line arguments, you'd need to use a loop, e.g.\n```\nfor(int i = 0; i < args.length; i++){\n    System.out.print(args[i]);\n}\nSystem.out.println();\n```\n\nanswered Aug 14, 2009 at 19:03\n\n[![quanticle's user avatar](https:\/\/www.gravatar.com\/avatar\/31fa94a51ce1eb3edd1fefbfcd684484?s=64&d=identicon&r=PG)](https:\/\/stackoverflow.com\/users\/149125\/quanticle)\n\n[quanticle](https:\/\/stackoverflow.com\/users\/149125\/quanticle)\n\n5,0706 gold badges35 silver badges42 bronze badges\n\nComments\n\nStart asking to get answers\n\nFind the answer to your question by asking.\n\n[Ask question](https:\/\/stackoverflow.com\/questions\/ask)\n\nExplore related questions\n\nSee similar questions with these tags.","meta_canonical":null}

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Boilerpipe Text	This question shows research effort; it is useful and clear 146 Save this question. Show activity on this post. I have a compiled java class: Echo.class public class Echo { public static void main (String arg) { System.out.println(arg); } } I cd to the directory and enter: java Echo "hello" I get this error: C:\Documents and Settings\joe\My Documents\projects\Misc\bin>java Echo "hello" Exception in thread "main" java.lang.NoClassDefFoundError: Echo Caused by: java.lang.ClassNotFoundException: Echo at java.net.URLClassLoader$ 1. run(Unknown Source) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at java.lang.ClassLoader.loadClassInternal(Unknown Source) Could not find the main class: Echo. Program will exit. What is the simplest way to get my java code in a form that I can run from the command line as apposed to having to use Eclipse IDE? Mel 6,105 10 gold badges 40 silver badges 42 bronze badges asked Aug 14, 2009 at 18:52 1 This answer is useful 144 Save this answer. Show activity on this post. Try: java -cp . Echo "hello" Assuming that you compiled with: javac Echo.java Then there is a chance that the "current" directory is not in your classpath ( where java looks for .class definitions ) If that's the case and listing the contents of your dir displays: Echo.java Echo.class Then any of this may work: java -cp . Echo "hello" or SET CLASSPATH=%CLASSPATH;. java Echo "hello" And later as Fredrik points out you'll get another error message like. Exception in thread "main" java.lang.NoSuchMethodError: main When that happens, go and read his answer :) answered Aug 14, 2009 at 18:53 1 Comment The -cp . to tell Java that he should add . (current working directory) to the classpath, meaning the place where he is looking for code. 2009-08-14T19:24:39.143Z+00:00 This answer is useful 53 Save this answer. Show activity on this post. With Java 11 you won't have to go through this rigmarole anymore! Instead, you can do this: > java MyApp.java You don't have to compile beforehand, as it's all done in one step. You can get the Java 11 JDK here: JDK 11 GA Release answered Oct 4, 2018 at 6:12 Ryan Lundy 211k 41 gold badges 187 silver badges 216 bronze badges 1 Comment > copy C:\Desenv\workspaceServer\TestProject\src\WebServiceStandAlone\MyApp.java . /y && javac MyApp.java && java -cp . MyApp && del MyApp.class && del MyApp.java Some guys do prefer the old fashion way =) 2018-11-13T20:15:04.063Z+00:00 This answer is useful 21 Save this answer. Show activity on this post. You need to specify the classpath. This should do it: java -cp . Echo "hello" This tells java to use . (the current directory) as its classpath, i.e. the place where it looks for classes. Note than when you use packages, the classpath has to contain the root directory, not the package subdirectories. e.g. if your class is my.package.Echo and the .class file is bin/my/package/Echo.class , the correct classpath directory is bin . answered Aug 14, 2009 at 18:54 Comments This answer is useful 21 Save this answer. Show activity on this post. You have no valid main method... The signature should be: public static void main( String[] args); Hence, in your case the code should look like this: public class Echo { public static void main (String[] arg) { System.out.println(arg[ 0 ]); } } Edit: Please note that Oscar is also right in that you are missing . in your classpath, you would run into the problem I solve after you have dealt with that error. answered Aug 14, 2009 at 18:54 Fredrik 5,859 2 gold badges 29 silver badges 33 bronze badges 2 Comments The only one to give the right result with newer java's. 2023-09-03T12:42:17.977Z+00:00 Keep in mind this thread dates back to 2009 :-) 2023-09-08T07:30:46.43Z+00:00 This answer is useful 8 Save this answer. Show activity on this post. If you have in your java source package mypackage; and your class is hello.java with public class hello { and in that hello.java you have public static void main (String[] args) { Then (after compilation) changeDir (cd) to the directory where your hello.class is. Then java -cp . mypackage.hello Mind the current directory and the package name before the class name. It works for my on linux mint and i hope on the other os's also Thanks Stack overflow for a wealth of info. answered Mar 17, 2018 at 8:22 1 Comment This answer is useful 3 Save this answer. Show activity on this post. My situation was a little complicated. I had to do three steps since I was using a .dll in the resources directory, for JNI code. My files were S:\Accessibility\tools\src\main\resources\dlls\HelloWorld.dll S:\Accessibility\tools\src\test\java\com\accessibility\HelloWorld.class My code contained the following line System.load(HelloWorld.class.getResource( "/dlls/HelloWorld.dll" ).getPath()); First, I had to move to the classpath directory cd /D "S:\Accessibility\tools\src\test\java" Next, I had to change the classpath to point to the current directory so that my class would be loaded and I had to change the classpath to point to he resources directory so my dll would be loaded. set classpath=%classpath%;.;..\..\..\src\main\resources; Then, I had to run java using the classname. java com.accessibility.HelloWorld answered Aug 10, 2013 at 1:30 Scott Izu 2,319 25 silver badges 14 bronze badges Comments This answer is useful 0 Save this answer. Show activity on this post. First, have you compiled the class using the command line javac compiler? Second, it seems that your main method has an incorrect signature - it should be taking in an array of String objects, rather than just one: public static void main (String[] args) { Once you've changed your code to take in an array of String objects, then you need to make sure that you're printing an element of the array, rather than array itself: System.out.println(args[ 0 ]) If you want to print the whole list of command line arguments, you'd need to use a loop, e.g. for ( int i = 0 ; i < args.length; i++){ System.out.print(args[i]); } System.out.println(); answered Aug 14, 2009 at 19:03 quanticle 5,070 6 gold badges 35 silver badges 42 bronze badges Comments Start asking to get answers Find the answer to your question by asking. Ask question Explore related questions See similar questions with these tags.
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[Explore Stack Internal](https://stackoverflow.co/internal/?utm_medium=referral&utm_source=stackoverflow-community&utm_campaign=side-bar&utm_content=explore-teams-compact-popover) # [How to execute a java .class from the command line](https://stackoverflow.com/questions/1279542/how-to-execute-a-java-class-from-the-command-line) [Ask Question](https://stackoverflow.com/questions/ask) Asked 16 years, 7 months ago Modified [3 years, 8 months ago](https://stackoverflow.com/questions/1279542/how-to-execute-a-java-class-from-the-command-line?lastactivity "2022-06-18 04:27:08Z") Viewed 529k times This question shows research effort; it is useful and clear 146 Save this question. Show activity on this post. I have a compiled java class: Echo.class ``` Copy ``` I `cd` to the directory and enter: `java Echo "hello"` I get this error: ``` Copy ``` What is the simplest way to get my java code in a form that I can run from the command line as apposed to having to use Eclipse IDE? - [java](https://stackoverflow.com/questions/tagged/java "show questions tagged 'java'") [Share](https://stackoverflow.com/q/1279542 "Short permalink to this question") Share a link to this question Copy link [CC BY-SA 3.0](https://creativecommons.org/licenses/by-sa/3.0/ "The current license for this post: CC BY-SA 3.0") [Improve this question](https://stackoverflow.com/posts/1279542/edit) Follow Follow this question to receive notifications [edited Apr 27, 2017 at 10:38](https://stackoverflow.com/posts/1279542/revisions "show all edits to this post") [![Mel's user avatar](https://i.sstatic.net/c8sPO.png?s=64)](https://stackoverflow.com/users/4720935/mel) [Mel](https://stackoverflow.com/users/4720935/mel) 6,1051010 gold badges4040 silver badges4242 bronze badges asked Aug 14, 2009 at 18:52 [![joe's user avatar](https://www.gravatar.com/avatar/aa22bf0ceed78fdc4f3753d5d24c80de?s=64&d=identicon&r=PG)](https://stackoverflow.com/users/5653/joe) [joe](https://stackoverflow.com/users/5653/joe) 17\.6k3737 gold badges9999 silver badges134134 bronze badges 1 - 22 Suggestion: The original question would, perhaps, better be left unedited in order not to invalidate the answers, under a quick review. Really weird to see the right method signature and then a bunch of answers that say it was incorrect. Erroneous code is supposed to be left that, for the purpose of comparison with the correct version, at least. JSmyth – [JSmyth](https://stackoverflow.com/users/588966/jsmyth "1,504 reputation") 2014-02-03 09:34:18 +00:00 [Commented Feb 3, 2014 at 9:34](https://stackoverflow.com/questions/1279542/how-to-execute-a-java-class-from-the-command-line#comment32497877_1279542) [Add a comment](https://stackoverflow.com/questions/1279542/how-to-execute-a-java-class-from-the-command-line "Use comments to ask for more information or suggest improvements. Avoid answering questions in comments.") \\| ## 7 Answers 7 Sorted by: [Reset to default](https://stackoverflow.com/questions/1279542/how-to-execute-a-java-class-from-the-command-line?answertab=scoredesc#tab-top) This answer is useful 144 Save this answer. Show activity on this post. Try: ``` Copyjava -cp . Echo "hello" ``` *** Assuming that you compiled with: ``` Copyjavac Echo.java ``` Then there is a chance that the "current" directory is not in your classpath ( where java looks for .class definitions ) If that's the case and listing the contents of your dir displays: ``` Copy ``` Then any of this may work: ``` Copyjava -cp . Echo "hello" ``` or ``` Copy ``` And later as [Fredrik](https://stackoverflow.com/questions/1279542/how-to-execute-a-java-class-from-the-command-line/1279560#1279560) points out you'll get another error message like. > Exception in thread "main" java.lang.NoSuchMethodError: main When that happens, go and read his answer :) [Share](https://stackoverflow.com/a/1279556 "Short permalink to this answer") Share a link to this answer Copy link [CC BY-SA 2.5](https://creativecommons.org/licenses/by-sa/2.5/ "The current license for this post: CC BY-SA 2.5") [Improve this answer](https://stackoverflow.com/posts/1279556/edit) Follow Follow this answer to receive notifications [edited May 23, 2017 at 10:31](https://stackoverflow.com/posts/1279556/revisions "show all edits to this post") [![Community's user avatar](https://www.gravatar.com/avatar/a007be5a61f6aa8f3e85ae2fc18dd66e?s=64&d=identicon&r=PG)](https://stackoverflow.com/users/-1/community) [Community](https://stackoverflow.com/users/-1/community)Bot 111 silver badge answered Aug 14, 2009 at 18:53 [![OscarRyz's user avatar](https://www.gravatar.com/avatar/94066dfa49c2feb14706cb081848fda7?s=64&d=identicon&r=PG)](https://stackoverflow.com/users/20654/oscarryz) [OscarRyz](https://stackoverflow.com/users/20654/oscarryz) 200k119119 gold badges399399 silver badges577577 bronze badges Sign up to request clarification or add additional context in comments. ## 1 Comment Add a comment [![](https://www.gravatar.com/avatar/826f4d6edd2e93e07aacd04bf07da069?s=48&d=identicon&r=PG)](https://stackoverflow.com/users/59572/fredrik) Fredrik [Fredrik](https://stackoverflow.com/users/59572/fredrik) [Over a year ago](https://stackoverflow.com/questions/1279542/how-to-execute-a-java-class-from-the-command-line#comment1108622_1279556) The -cp . to tell Java that he should add . (current working directory) to the classpath, meaning the place where he is looking for code. 2009-08-14T19:24:39.143Z+00:00 3 Reply - Copy link This answer is useful 53 Save this answer. Show activity on this post. With Java 11 you won't have to go through this rigmarole anymore\! Instead, you can do this: ``` Copy> java MyApp.java ``` You don't have to compile beforehand, as it's all done in one step. You can get the Java 11 JDK here: [JDK 11 GA Release](https://jdk.java.net/11/) [Share](https://stackoverflow.com/a/52640128 "Short permalink to this answer") Share a link to this answer Copy link [CC BY-SA 4.0](https://creativecommons.org/licenses/by-sa/4.0/ "The current license for this post: CC BY-SA 4.0") [Improve this answer](https://stackoverflow.com/posts/52640128/edit) Follow Follow this answer to receive notifications answered Oct 4, 2018 at 6:12 [![Ryan Lundy's user avatar](https://www.gravatar.com/avatar/750159e9cdab58c4b6547d382311c9af?s=64&d=identicon&r=PG)](https://stackoverflow.com/users/5486/ryan-lundy) [Ryan Lundy](https://stackoverflow.com/users/5486/ryan-lundy) 211k4141 gold badges187187 silver badges216216 bronze badges ## 1 Comment Add a comment [![](https://i.sstatic.net/1O0b6.jpg?s=64)](https://stackoverflow.com/users/929263/jr) Jr. [Jr.](https://stackoverflow.com/users/929263/jr) [Over a year ago](https://stackoverflow.com/questions/1279542/how-to-execute-a-java-class-from-the-command-line#comment93459597_52640128) \> copy C:\\Desenv\\workspaceServer\\TestProject\\src\\WebServiceStandAlone\\MyApp.java . /y && javac MyApp.java && java -cp . MyApp && del MyApp.class && del MyApp.java Some guys do prefer the old fashion way =) 2018-11-13T20:15:04.063Z+00:00 0 Reply - Copy link This answer is useful 21 Save this answer. Show activity on this post. You need to specify the classpath. This should do it: ``` Copyjava -cp . Echo "hello" ``` This tells java to use `.` (the current directory) as its classpath, i.e. the place where it looks for classes. Note than when you use packages, the classpath has to contain the root directory, not the package subdirectories. e.g. if your class is `my.package.Echo` and the .class file is `bin/my/package/Echo.class`, the correct classpath directory is `bin`. [Share](https://stackoverflow.com/a/1279559 "Short permalink to this answer") Share a link to this answer Copy link [CC BY-SA 2.5](https://creativecommons.org/licenses/by-sa/2.5/ "The current license for this post: CC BY-SA 2.5") [Improve this answer](https://stackoverflow.com/posts/1279559/edit) Follow Follow this answer to receive notifications answered Aug 14, 2009 at 18:54 [![Michael Borgwardt's user avatar](https://www.gravatar.com/avatar/0382297f273df0a544b0c6c2734de096?s=64&d=identicon&r=PG)](https://stackoverflow.com/users/16883/michael-borgwardt) [Michael Borgwardt](https://stackoverflow.com/users/16883/michael-borgwardt) 347k8181 gold badges491491 silver badges726726 bronze badges ## Comments Add a comment This answer is useful 21 Save this answer. Show activity on this post. You have no valid main method... The signature should be: public static void main(String\[\] args); Hence, in your case the code should look like this: ``` Copy ``` Edit: Please note that [Oscar](https://stackoverflow.com/questions/1279542/how-to-execute-a-java-class-from-the-command-line/1279556#1279556) is also right in that you are missing . in your classpath, you would run into the problem I solve after you have dealt with that error. [Share](https://stackoverflow.com/a/1279560 "Short permalink to this answer") Share a link to this answer Copy link [CC BY-SA 3.0](https://creativecommons.org/licenses/by-sa/3.0/ "The current license for this post: CC BY-SA 3.0") [Improve this answer](https://stackoverflow.com/posts/1279560/edit) Follow Follow this answer to receive notifications [edited May 23, 2017 at 12:02](https://stackoverflow.com/posts/1279560/revisions "show all edits to this post") [![Community's user avatar](https://www.gravatar.com/avatar/a007be5a61f6aa8f3e85ae2fc18dd66e?s=64&d=identicon&r=PG)](https://stackoverflow.com/users/-1/community) [Community](https://stackoverflow.com/users/-1/community)Bot 111 silver badge answered Aug 14, 2009 at 18:54 [![Fredrik's user avatar](https://www.gravatar.com/avatar/826f4d6edd2e93e07aacd04bf07da069?s=64&d=identicon&r=PG)](https://stackoverflow.com/users/59572/fredrik) [Fredrik](https://stackoverflow.com/users/59572/fredrik) 5,85922 gold badges2929 silver badges3333 bronze badges ## 2 Comments Add a comment [![](https://www.gravatar.com/avatar/481b12c3fecaf223af0522000fbcb531?s=48&d=identicon&r=PG&f=y&so-version=2)](https://stackoverflow.com/users/4952917/erich-k%C3%BCster) Erich Küster [Erich Küster](https://stackoverflow.com/users/4952917/erich-k%C3%BCster) [Over a year ago](https://stackoverflow.com/questions/1279542/how-to-execute-a-java-class-from-the-command-line#comment135798271_1279560) The only one to give the right result with newer java's. 2023-09-03T12:42:17.977Z+00:00 0 Reply - Copy link [![](https://www.gravatar.com/avatar/826f4d6edd2e93e07aacd04bf07da069?s=48&d=identicon&r=PG)](https://stackoverflow.com/users/59572/fredrik) Fredrik [Fredrik](https://stackoverflow.com/users/59572/fredrik) [Over a year ago](https://stackoverflow.com/questions/1279542/how-to-execute-a-java-class-from-the-command-line#comment135857198_1279560) Keep in mind this thread dates back to 2009 :-) 2023-09-08T07:30:46.43Z+00:00 0 Reply - Copy link This answer is useful 8 Save this answer. Show activity on this post. If you have in your java source ``` Copypackage mypackage; ``` and your class is hello.java with ``` Copypublic class hello { ``` and in that hello.java you have ``` Copy public static void main(String[] args) { ``` Then (after compilation) changeDir (cd) to the directory where your hello.class is. Then ``` Copyjava -cp . mypackage.hello ``` Mind the current directory and the package name before the class name. It works for my on linux mint and i hope on the other os's also Thanks Stack overflow for a wealth of info. [Share](https://stackoverflow.com/a/49333968 "Short permalink to this answer") Share a link to this answer Copy link [CC BY-SA 3.0](https://creativecommons.org/licenses/by-sa/3.0/ "The current license for this post: CC BY-SA 3.0") [Improve this answer](https://stackoverflow.com/posts/49333968/edit) Follow Follow this answer to receive notifications answered Mar 17, 2018 at 8:22 [![Gerard Doets's user avatar](https://www.gravatar.com/avatar/835cd24768924bfe5ec75bae4c72ad4e?s=64&d=identicon&r=PG&f=y&so-version=2)](https://stackoverflow.com/users/8344297/gerard-doets) [Gerard Doets](https://stackoverflow.com/users/8344297/gerard-doets) 8111 silver badge22 bronze badges ## 1 Comment Add a comment [![](https://www.gravatar.com/avatar/600a453e63e5e8d9f735e91cdc5cb839?s=48&d=identicon&r=PG)](https://stackoverflow.com/users/1300170/ruvim) ruvim [ruvim](https://stackoverflow.com/users/1300170/ruvim) [Over a year ago](https://stackoverflow.com/questions/1279542/how-to-execute-a-java-class-from-the-command-line#comment87017442_49333968) NB: the class file should be foundable via `./mypackage/hello.class` name. See also: "[Running java in package from command line](https://stackoverflow.com/questions/19433366/running-java-in-package-from-command-line)" question. 2018-04-24T11:40:03.46Z+00:00 3 Reply - Copy link This answer is useful 3 Save this answer. Show activity on this post. My situation was a little complicated. I had to do three steps since I was using a .dll in the resources directory, for JNI code. My files were ``` Copy ``` My code contained the following line ``` CopySystem.load(HelloWorld.class.getResource("/dlls/HelloWorld.dll").getPath()); ``` First, I had to move to the classpath directory ``` Copycd /D "S:\Accessibility\tools\src\test\java" ``` Next, I had to change the classpath to point to the current directory so that my class would be loaded and I had to change the classpath to point to he resources directory so my dll would be loaded. ``` Copyset classpath=%classpath%;.;..\..\..\src\main\resources; ``` Then, I had to run java using the classname. ``` Copyjava com.accessibility.HelloWorld ``` [Share](https://stackoverflow.com/a/18157831 "Short permalink to this answer") Share a link to this answer Copy link [CC BY-SA 3.0](https://creativecommons.org/licenses/by-sa/3.0/ "The current license for this post: CC BY-SA 3.0") [Improve this answer](https://stackoverflow.com/posts/18157831/edit) Follow Follow this answer to receive notifications answered Aug 10, 2013 at 1:30 [![Scott Izu's user avatar](https://www.gravatar.com/avatar/da28e044b5207cc1dff86a86cb31432d?s=64&d=identicon&r=PG)](https://stackoverflow.com/users/2663340/scott-izu) [Scott Izu](https://stackoverflow.com/users/2663340/scott-izu) 2,3192525 silver badges1414 bronze badges ## Comments Add a comment This answer is useful 0 Save this answer. Show activity on this post. First, have you compiled the class using the command line javac compiler? Second, it seems that your main method has an incorrect signature - it should be taking in an array of String objects, rather than just one: ``` Copypublic static void main(String[] args){ ``` Once you've changed your code to take in an array of String objects, then you need to make sure that you're printing an element of the array, rather than array itself: ``` CopySystem.out.println(args[0]) ``` If you want to print the whole list of command line arguments, you'd need to use a loop, e.g. ``` Copy ``` [Share](https://stackoverflow.com/a/1279608 "Short permalink to this answer") Share a link to this answer Copy link [CC BY-SA 2.5](https://creativecommons.org/licenses/by-sa/2.5/ "The current license for this post: CC BY-SA 2.5") [Improve this answer](https://stackoverflow.com/posts/1279608/edit) Follow Follow this answer to receive notifications answered Aug 14, 2009 at 19:03 [![quanticle's user avatar](https://www.gravatar.com/avatar/31fa94a51ce1eb3edd1fefbfcd684484?s=64&d=identicon&r=PG)](https://stackoverflow.com/users/149125/quanticle) [quanticle](https://stackoverflow.com/users/149125/quanticle) 5,07066 gold badges3535 silver badges4242 bronze badges ## Comments Add a comment Start asking to get answers Find the answer to your question by asking. 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Readable Markdown	This question shows research effort; it is useful and clear 146 Save this question. Show activity on this post. I have a compiled java class: Echo.class ``` public class Echo { public static void main (String arg) { System.out.println(arg); } } ``` I `cd` to the directory and enter: `java Echo "hello"` I get this error: ``` C:\Documents and Settings\joe\My Documents\projects\Misc\bin>java Echo "hello" Exception in thread "main" java.lang.NoClassDefFoundError: Echo Caused by: java.lang.ClassNotFoundException: Echo at java.net.URLClassLoader$1.run(Unknown Source) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at java.lang.ClassLoader.loadClassInternal(Unknown Source) Could not find the main class: Echo. Program will exit. ``` What is the simplest way to get my java code in a form that I can run from the command line as apposed to having to use Eclipse IDE? [![Mel's user avatar](https://i.sstatic.net/c8sPO.png?s=64)](https://stackoverflow.com/users/4720935/mel) [Mel](https://stackoverflow.com/users/4720935/mel) 6,10510 gold badges40 silver badges42 bronze badges asked Aug 14, 2009 at 18:52 [![joe's user avatar](https://www.gravatar.com/avatar/aa22bf0ceed78fdc4f3753d5d24c80de?s=64&d=identicon&r=PG)](https://stackoverflow.com/users/5653/joe) 1 This answer is useful 144 Save this answer. Show activity on this post. Try: ``` java -cp . Echo "hello" ``` *** Assuming that you compiled with: ``` javac Echo.java ``` Then there is a chance that the "current" directory is not in your classpath ( where java looks for .class definitions ) If that's the case and listing the contents of your dir displays: ``` Echo.java Echo.class ``` Then any of this may work: ``` java -cp . Echo "hello" ``` or ``` SET CLASSPATH=%CLASSPATH;. java Echo "hello" ``` And later as [Fredrik](https://stackoverflow.com/questions/1279542/how-to-execute-a-java-class-from-the-command-line/1279560#1279560) points out you'll get another error message like. > Exception in thread "main" java.lang.NoSuchMethodError: main When that happens, go and read his answer :) [![Community's user avatar](https://www.gravatar.com/avatar/a007be5a61f6aa8f3e85ae2fc18dd66e?s=64&d=identicon&r=PG)](https://stackoverflow.com/users/-1/community) answered Aug 14, 2009 at 18:53 [![OscarRyz's user avatar](https://www.gravatar.com/avatar/94066dfa49c2feb14706cb081848fda7?s=64&d=identicon&r=PG)](https://stackoverflow.com/users/20654/oscarryz) 1 Comment [![](https://www.gravatar.com/avatar/826f4d6edd2e93e07aacd04bf07da069?s=48&d=identicon&r=PG)](https://stackoverflow.com/users/59572/fredrik) The -cp . to tell Java that he should add . (current working directory) to the classpath, meaning the place where he is looking for code. 2009-08-14T19:24:39.143Z+00:00 This answer is useful 53 Save this answer. Show activity on this post. With Java 11 you won't have to go through this rigmarole anymore\! Instead, you can do this: ``` > java MyApp.java ``` You don't have to compile beforehand, as it's all done in one step. You can get the Java 11 JDK here: [JDK 11 GA Release](https://jdk.java.net/11/) answered Oct 4, 2018 at 6:12 [![Ryan Lundy's user avatar](https://www.gravatar.com/avatar/750159e9cdab58c4b6547d382311c9af?s=64&d=identicon&r=PG)](https://stackoverflow.com/users/5486/ryan-lundy) [Ryan Lundy](https://stackoverflow.com/users/5486/ryan-lundy) 211k41 gold badges187 silver badges216 bronze badges 1 Comment [![](https://i.sstatic.net/1O0b6.jpg?s=64)](https://stackoverflow.com/users/929263/jr) \> copy C:\\Desenv\\workspaceServer\\TestProject\\src\\WebServiceStandAlone\\MyApp.java . /y && javac MyApp.java && java -cp . MyApp && del MyApp.class && del MyApp.java Some guys do prefer the old fashion way =) 2018-11-13T20:15:04.063Z+00:00 This answer is useful 21 Save this answer. Show activity on this post. You need to specify the classpath. This should do it: ``` java -cp . Echo "hello" ``` This tells java to use `.` (the current directory) as its classpath, i.e. the place where it looks for classes. Note than when you use packages, the classpath has to contain the root directory, not the package subdirectories. e.g. if your class is `my.package.Echo` and the .class file is `bin/my/package/Echo.class`, the correct classpath directory is `bin`. answered Aug 14, 2009 at 18:54 [![Michael Borgwardt's user avatar](https://www.gravatar.com/avatar/0382297f273df0a544b0c6c2734de096?s=64&d=identicon&r=PG)](https://stackoverflow.com/users/16883/michael-borgwardt) Comments This answer is useful 21 Save this answer. Show activity on this post. You have no valid main method... The signature should be: public static void main(String\[\] args); Hence, in your case the code should look like this: ``` public class Echo { public static void main (String[] arg) { System.out.println(arg[0]); } } ``` Edit: Please note that [Oscar](https://stackoverflow.com/questions/1279542/how-to-execute-a-java-class-from-the-command-line/1279556#1279556) is also right in that you are missing . in your classpath, you would run into the problem I solve after you have dealt with that error. [![Community's user avatar](https://www.gravatar.com/avatar/a007be5a61f6aa8f3e85ae2fc18dd66e?s=64&d=identicon&r=PG)](https://stackoverflow.com/users/-1/community) answered Aug 14, 2009 at 18:54 [![Fredrik's user avatar](https://www.gravatar.com/avatar/826f4d6edd2e93e07aacd04bf07da069?s=64&d=identicon&r=PG)](https://stackoverflow.com/users/59572/fredrik) [Fredrik](https://stackoverflow.com/users/59572/fredrik) 5,8592 gold badges29 silver badges33 bronze badges 2 Comments [![](https://www.gravatar.com/avatar/481b12c3fecaf223af0522000fbcb531?s=48&d=identicon&r=PG&f=y&so-version=2)](https://stackoverflow.com/users/4952917/erich-k%C3%BCster) The only one to give the right result with newer java's. 2023-09-03T12:42:17.977Z+00:00 [![](https://www.gravatar.com/avatar/826f4d6edd2e93e07aacd04bf07da069?s=48&d=identicon&r=PG)](https://stackoverflow.com/users/59572/fredrik) Keep in mind this thread dates back to 2009 :-) 2023-09-08T07:30:46.43Z+00:00 This answer is useful 8 Save this answer. Show activity on this post. If you have in your java source ``` package mypackage; ``` and your class is hello.java with ``` public class hello { ``` and in that hello.java you have ``` public static void main(String[] args) { ``` Then (after compilation) changeDir (cd) to the directory where your hello.class is. Then ``` java -cp . mypackage.hello ``` Mind the current directory and the package name before the class name. It works for my on linux mint and i hope on the other os's also Thanks Stack overflow for a wealth of info. answered Mar 17, 2018 at 8:22 [![Gerard Doets's user avatar](https://www.gravatar.com/avatar/835cd24768924bfe5ec75bae4c72ad4e?s=64&d=identicon&r=PG&f=y&so-version=2)](https://stackoverflow.com/users/8344297/gerard-doets) 1 Comment [![](https://www.gravatar.com/avatar/600a453e63e5e8d9f735e91cdc5cb839?s=48&d=identicon&r=PG)](https://stackoverflow.com/users/1300170/ruvim) This answer is useful 3 Save this answer. Show activity on this post. My situation was a little complicated. I had to do three steps since I was using a .dll in the resources directory, for JNI code. My files were ``` S:\Accessibility\tools\src\main\resources\dlls\HelloWorld.dll S:\Accessibility\tools\src\test\java\com\accessibility\HelloWorld.class ``` My code contained the following line ``` System.load(HelloWorld.class.getResource("/dlls/HelloWorld.dll").getPath()); ``` First, I had to move to the classpath directory ``` cd /D "S:\Accessibility\tools\src\test\java" ``` Next, I had to change the classpath to point to the current directory so that my class would be loaded and I had to change the classpath to point to he resources directory so my dll would be loaded. ``` set classpath=%classpath%;.;..\..\..\src\main\resources; ``` Then, I had to run java using the classname. ``` java com.accessibility.HelloWorld ``` answered Aug 10, 2013 at 1:30 [![Scott Izu's user avatar](https://www.gravatar.com/avatar/da28e044b5207cc1dff86a86cb31432d?s=64&d=identicon&r=PG)](https://stackoverflow.com/users/2663340/scott-izu) [Scott Izu](https://stackoverflow.com/users/2663340/scott-izu) 2,31925 silver badges14 bronze badges Comments This answer is useful 0 Save this answer. Show activity on this post. First, have you compiled the class using the command line javac compiler? Second, it seems that your main method has an incorrect signature - it should be taking in an array of String objects, rather than just one: ``` public static void main(String[] args){ ``` Once you've changed your code to take in an array of String objects, then you need to make sure that you're printing an element of the array, rather than array itself: ``` System.out.println(args[0]) ``` If you want to print the whole list of command line arguments, you'd need to use a loop, e.g. ``` for(int i = 0; i < args.length; i++){ System.out.print(args[i]); } System.out.println(); ``` answered Aug 14, 2009 at 19:03 [![quanticle's user avatar](https://www.gravatar.com/avatar/31fa94a51ce1eb3edd1fefbfcd684484?s=64&d=identicon&r=PG)](https://stackoverflow.com/users/149125/quanticle) [quanticle](https://stackoverflow.com/users/149125/quanticle) 5,0706 gold badges35 silver badges42 bronze badges Comments Start asking to get answers Find the answer to your question by asking. 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