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For some reason, I cannot run my Java code in command prompt

 
Greenhorn
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Hello. I have been programming Java for a while now, but I've always only used IDE's such as eclipse.  
But, when I had to test Console.readPassword(), Eclipse wouldn't work. So I had to use the command prompt to test it.  
But after hours of searching, I still cannot find out why it tells me it cannot find the main class, when I explicitly point to it.  
Here is my file hierarchy and my command.
D:\Java projects\Irrelevant folder1
                        Irrelevant folder 2
                        JavaEms\bin\ems\[.class files. Including the Main.class]
                                      src\ems\[.Java files.]
                                      .classpath
                                      .project
                                      3 .txt's used by the app
And the command is : Java -classpath D:\Java_projects\JavaEms\bin ems.Main
And it tells me that it cannot find or load main class ems.Main.
Any help is appreciated.
 
Marshal
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I am having difficulty finding an error in that information you have posted. Please show us the package declaration in your Main class.

I never use Console. When it came out it was a great thing, but there is a serious problem with Console. If you export your app as an executable .jar, your users will probably open it with javaw rather than java at the command line/terminal, and there won't be a visible Console and System.console() will return null. So any attempt to use the console will cause an exceeption to be thrown.
 
Saloon Keeper
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Maybe because you have an underscore in Java_projects, and that's not the name of the folder?
 
F Lucas
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Hello. Thanks for the reply. I do not know how to quote you two, so I will reply in a list.
Campbell : Is a package declaration this? -> package ems;
Also, what would be a good alternative to console?
Stephan : Without an underscore, it ends up searching for a main class called projects\JavaEms\bin ems.Main
Because the command ends up getting separated on the space.
 
Rancher
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You can't just put an underscore in there because of that, as 'Java_projects' != 'Java projects'.

Put the classpath in quotes:
java -classpath "D:\Java projects\JavaEms\bin" ems.Main
 
Campbell Ritchie
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F Lucas wrote:. . . Campbell : Is a package declaration this? -> package ems;

Yes. And I missed the underscore: good catch, Stephan.

Also, what would be a good alternative to console?  . . ..

Consider a GUI with a password field. There is such a class but I have forgotten its correct name. Maybe JPasswordField.
 
F Lucas
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Thanks to Stephan and Dave, it now works. Thank you.
Also thanks to Campbell for the tip about not using console.
 
Campbell Ritchie
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That's a pleasure
 
It is sorta covered in the JavaRanch Style Guide.
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