The Clover Eclipse Plugin allows you to instrument your Java code easily from within the Eclipse Java IDE, and to view your coverage results inside Eclipse.
We recommend starting your adventure with Clover for Eclipse with a following lecture:
If you need more details how given features work, or how to efficiently work with Clover, you can read about:
If you work with Ant-based projects under Eclipse IDE, read the:
For more advanced topics, like performance tuning or instrumentation of RCP application, see:
See the Eclipse Plugin FAQ. You can also search posts with the clover tag on Atlassian Answers.