CODEWITHSUNDEEP
javapackage
Sukhbir
Sukhbir

Reputation: 661

Relationship between a package statement and the directory of a .java file?

Consider a package hierarchy folder1/hi. folder1 contains B.java and hi contains A.java.

B.java:

package hi.a12.pkg;
public class B { }

A.java:

package a12.pkg;
public class A {B b; }

Now B.java compiles successfully, but A.java does not.

Since both should produce class files in same location. Hence they should be able to find each other without import statement.

But still It says class B not found.

Anyone suggest the measures...or whats going wrong..

Upvotes: 3

Views: 1414

Answers (2)

Chetan Kinger
Chetan Kinger

Reputation: 15212

Consider a package hierarchy folder1/hi. folder1 contains B.java and hi contains A.java.

So B.java is in folder1 and A.java is in a folder named hi. So far so good.

B.java looks like this :

package hi.a12.pkg;
public class B { }

Oops. B.java says that it is in a package named hi.a12.pkg and yet it's physical location on the disk is folder1. That's where the problem is. Put your files in the folder indicated by the package statement or else other classes will not be able to find them.

A quick way to understand the concept and fix your problem would be to :

  1. Change the package statement in B.java to package folder1;.
  2. Change the package statement in A.java to package folder1.hi;
  3. import B in A.java after the package statement as import folder.B;
  4. Compile B.java from one directory above folder1 as javac folder1\B.java
  5. Compile A.java from one directory above folder1 as javac folder1\hi\A.java

You can read all about it in the Oracle documentation

Upvotes: 2

johnsgp
johnsgp

Reputation: 103

There are several problems.

First, it looks like your packages are named the wrong way around. Try

for A.java (which should be in the directory ..../pkg/a12):

package pkg.a12;

for B.java (which must be in the directory .../pkg/a12/hi):

package pkg.a12.hi;

Second, your file A.java needs to say where B is located using an import statement:

package pkg.a12;
import pkg.a12.hi.B;
public class A {B b; }

Third, when you compile A you must be in the folder above pkg and refer to the full path of A:

javac pkg/a12/A.java

This will also compile B.java

Upvotes: -1

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