通过源代码确定jar文件的优先级

Question

I have a java project in eclipse 3.2.1

I have a java class com.abc.Dinesh in source. And I also have a some jar file that has a class with the same name and package.

I imported the jar file in my project. However, in my source code when I'm referencing class Dinesh, the class is resolved to the source and not the binary version. I want to refer to the class file in from the jar.

How can I do this?

~Thanks

Answer 1

You could try the following:

right click on your project > Build Path > Configure Build Path...

Then go to the tab

Order and Export

Select (simple click) your jar and press Top or just Up until it is above the src entry.

Answer 2

The only way to resolve your problem (within or outside Eclipse) is to code you own ClassLoader to prioritize Jar files over class files. :

see http://kalanir.blogspot.fr/2010/01/how-to-write-custom-class-loader-to.html

And then setting the jvm "java.system.class.loader" property with the new one

Answer 3

Workaround : Do not refer to the .java files. Remove the .java file / move it to a different project? and do not refer to that project in this, only to the jar, either directly or to a copy of the version you want in your lib

Answer 4

The load order of classloaders is Bootstrap CL-->System CL-->Extended CL

Now the jar & your source files are in System CL. Move the JAR file to ext folder in you JDK. That way you give precedence to classes on system classpath over jars.

Answer 5

If you have two class with same name in classpath in different packages. In this case if you are using both the class in same code you will need to qualify with its package. eg to reference Dinesh you will need to do something like

com.abc.Dinesh dinesh = new com.abc.Dinesh();