# Incompatibilities between Eclipse JDT 3.1 and 3.2

Eclipse changed in incompatible ways between 3.1 and 3.2 in ways that affect plug-ins. The following entries describe the areas that changed and provide instructions for migrating 3.1 plug-ins to 3.2. Note that you only need to look here if you are experiencing problems running your 3.1 plug-in on 3.2.

1. API contract changes to IJavaReferenceType

## 1. API contract changes to IJavaReferenceType

What is affected: Clients that call `IJavaReferenceType.getClassLoaderObject()`.

Description: In Eclipse 3.1, the method `org.eclipse.jdt.debug.core.IJavaReferenceType.getClassLoaderObject()` was added to `IJavaReferenceType`. The method was not specified to return `null`, but could. In Eclipse 3.2, the specification has been updated to indicate that `null` is a valid return value. The behavior of the method has not changed, but callers should be aware that `null` can be returned and should add appropriate checks.

Action required: Clients calling `IJavaReferenceType.getClassLoaderObject()` should be modified to handle `null` as a return value.