Re: Issues with package declarations

From:

ankur <ankur.a.agarwal@gmail.com>

Newsgroups:

comp.lang.java.programmer

Date:

Sun, 3 Aug 2008 17:36:10 -0700 (PDT)

Message-ID:

<e40e0689-36e4-4330-ab33-9cb156856d24@t1g2000pra.googlegroups.com>

On Aug 3, 5:00 pm, Arne Vajh=F8j <a...@vajhoej.dk> wrote:

ankur wrote:

On Aug 3, 4:08 pm, Arne Vajh=F8j <a...@vajhoej.dk> wrote:

ankur wrote:

On Aug 3, 2:16 pm, Arne Vajh=F8j <a...@vajhoej.dk> wrote:

ankur wrote:

On Aug 3, 1:07 pm, Arne Vajh=F8j <a...@vajhoej.dk> wrote:

ankur wrote:

This is what my class path contains:
.;C:\Program Files\Java\jdk1.6.0\bin;C:\Documents and Settings\An=

kur

Agarwal\My Documents\eclipse\eclipse.exe;C:\Program Files\Java
\jre1.6.0_03\lib\ext\QTJava.zip;
My C:\Java Files contains thisisatest.java and NullTest.java
On windows cmd prompt I cd to C:\Java Files
and do
C:\Java Files>javac -d . NullTest.java
and then I do
C:\Java Files>javac thisisatest.java
which gives me the following error:
thisisatest.java:7: cannot access NullTest
bad class file: .\NullTest.java
file does not contain class NullTest
Please remove or make sure it appears in the correct subdirectory=

the classpath.
        NullTest var = new NullTest();
        ^
1 error
My NullTest.java contains:
package forpackagetest;
public class NullTest {
   final int c[] = {1,2};
           final int d[] = {1,2};
           //c = null;
    }
   class abc {
   }
   class def {
   }
My thisisatest.java contains:
import forpackagetest.*;
public class thisisatest {
public static void main ( String args[])
{
   NullTest var = new NullTest();
}
}
I do not understand why am I getting the error. Could you help ?

Package structure and directory structure must match.
package forpackagetest;
means that the files mus be:
forpackagetest\NullTest.java
forpackagetest\NullTest.class

So u r saying that I should create forpackagetest folder under C:\J=

ava

Files manually.

Yes.

Then what would be the use of :
C:\Java Files>javac -d . NullTest.java
command ?

You will use the same command down on the forpackagetest folder !

This does not make sense to me because I thought that -d option can
create the package subdirectory for you and to instantiate a class
object you only needed the .class files (I am instantiating NullTest
object in thisisatest ).

I forgot that.

So:

javac NullTest.java

or

javac -d .. NullTest.java

down in that dir.

Arne

I started off with :

C:\Java Files> dir
Volume in drive C has no label.
Volume Serial Number is 2EB8-82AA

Directory of C:\Java Files

08/03/2008 04:45 PM <DIR> .
08/03/2008 04:45 PM <DIR> ..
08/03/2008 11:40 AM 180 NullTest.java
08/03/2008 12:30 PM 144 thisisatest.java
2 File(s) 324 byt=

2 Dir(s) 30,197,694,464 bytes free

Then I did:
C:\Java Files>javac -d . NullTest.java

which led to :

C:\Java Files>dir
Volume in drive C has no label.
Volume Serial Number is 2EB8-82AA

Directory of C:\Java Files

08/03/2008 04:48 PM <DIR> .
08/03/2008 04:48 PM <DIR> ..
08/03/2008 04:48 PM <DIR> forpackagetest
08/03/2008 11:40 AM 180 NullTest.java
08/03/2008 12:30 PM 144 thisisatest.java
2 File(s) 324 byt=

3 Dir(s) 30,197,686,272 bytes free

And

C:\Java Files\forpackagetest>dir
Volume in drive C has no label.
Volume Serial Number is 2EB8-82AA

Directory of C:\Java Files\forpackagetest

08/03/2008 04:48 PM <DIR> .
08/03/2008 04:48 PM <DIR> ..
08/03/2008 04:48 PM 200 abc.class
08/03/2008 04:48 PM 200 def.class
08/03/2008 04:48 PM 292 NullTest.class
3 File(s) 692 byt=

               2 Dir(s) 30,197,686,272 bytes free

Now this gives error:

C:\Java Files>javac thisisatest.java
thisisatest.java:7: cannot access NullTest
bad class file: .\NullTest.java
file does not contain class NullTest
Please remove or make sure it appears in the correct subdirectory of
the classpath.
        NullTest var = new NullTest();
        ^
1 error

I specifically asked you to put NullTest.java down in that dir as well.

And you may need to use:

javac -classpath . thisisatest.java

(and it should be ThisIsATest.java)

My class path is:

.;C:\Program Files\Java\jdk1.6.0\bin;C:\Documents and Settings\Ankur
Agarwal\My Documents\eclipse\eclipse.exe;C:\Program Files\Java
\jre1.6.0_03\lib\ext\QTJava.zip;

bin dir + exe + zip in "class path" ? That will never work !

Arne

I had made that change. Okay forget that:

I have :

package testpack;

public class testclass {

public static void main (String args[])

{
    System.out.println("Hi there");
}

}

C:\Jfiles\testpack>dir
Volume in drive C has no label.
Volume Serial Number is 2EB8-82AA

Directory of C:\Jfiles\testpack

08/03/2008 05:32 PM <DIR> .
08/03/2008 05:32 PM <DIR> ..
08/03/2008 05:26 PM 135 testclass.java
               1 File(s) 135 bytes
               2 Dir(s) 30,197,583,872 bytes free

This works:

C:\Jfiles\testpack>javac testclass.java

Leads to :

C:\Jfiles\testpack>dir
Volume in drive C has no label.
Volume Serial Number is 2EB8-82AA

Directory of C:\Jfiles\testpack

08/03/2008 05:33 PM <DIR> .
08/03/2008 05:33 PM <DIR> ..
08/03/2008 05:33 PM 429 testclass.class
08/03/2008 05:26 PM 135 testclass.java
               2 File(s) 564 bytes
               2 Dir(s) 30,197,583,872 bytes free

Now why this error?? :

C:\Jfiles\testpack>java testclass
Exception in thread "main" java.lang.NoClassDefFoundError: testclass
(wrong name: testpack/testclass)
        at java.lang.ClassLoader.defineClass1(Native Method)
        at java.lang.ClassLoader.defineClass(Unknown Source)
        at java.security.SecureClassLoader.defineClass(Unknown Source)
        at java.net.URLClassLoader.defineClass(Unknown Source)
        at java.net.URLClassLoader.access$000(Unknown Source)
        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)

Thanks,