Cant use packages/classpaths correctly _ never could too
Hello,
I have a directory C:\DIR
In this directory I have a program. Two files both declare the package a.b package a.b;. Both files are in the directory C:\DIR\a\b.
One of my files is KeyInput.java which implements KeyListener for obvious reasons.
The second file is Main.java which has a Frame frame to which I want to add a KeyListener: frame.addKeyListener(new KeyInput()); Now, this works perfectly fine when I have KeyInput as an inner class, but using this (the above) architecture my compiler can't find KeyInput.
I have not set a classpath (though I did try that in my compiling command "javac -classpath C:\ Main.java", but that did not work).
I did check all sorts of documentation on this, so please don't answer that I should do just that. I can't get it running. Until now my remedy was not using packages, but I want to.
Please tell me what I am doing wrong,
Q
thanks
I now have another basic problem with these two classes, which concerns the concept "static".
Here's the problem:
When I add a KeyListener to frame as above I instantiate a KeyInput.
In KeyInput I for instance want to use a key to quit the program. (I also want a lot of other things, but
the same problem applies to them) To do this I create a method "public void kill( )" in Main. mainInst is
an instance of Main (created in the public static void main (String[] args) method), but my instance of KeyInput does not know him.
So now I have a problem. Because I either have to make my instance of KeyInput know mainInst so it
can do "mainInst.kill( )", which I do not know how to do; or I have to use the Main class itself. However:
Main.kill( ) does not work, because kill isn't static. I could make kill static, but then I have a static context
where I don't want any, for know I have a boolean running which has to be declared static etc. etc., and
then I'm not even talking about all the other things to do with the keys.
Ok, one solution is simple... make KeyInput an inner class of Main. But I don't want that! It will wreck
all the little beauty present in my programmature. So what do I do? How does a professional do this? It's such a basic problem I must know the answer.
Many thanks,
Q
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i've got files in a package com.one2one3.io, so i've got a directory structure
/com/one2one3/io/ and i'm wondering where is the generally accepted place to
put that, its working for now in ~/Code/com/one2one3/..., but then i have to
specify the classpath everytime i compile...Note that when the source file that is being compiled includes a package declaration at the top like
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but it isn't i still get class not found errors when compiling. Once you can isolate all of your class files into the classes directory, then you define the classpath as the classpath using the "-classpath" option of the javac command. You may want to include the current working directory too by including "./" with the option.
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http://java.sun.com/j2se/1.5.0/docs/tooldocs/solaris/javac.html#commandlineargfile
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