The checking of the @Nonnull and @Nullable annotations in Eclipse is an early beta. The largest problem is that there it no knowing over the null behavior of the Java API.
Are there any other plugins that are better currently?
It's now integrated in Eclipse Kepler.
I have found that FindBugs works well and is easy to use. FindBugs Plugin
Get Eclipse SDK 3.7(or Indigo) Enter this update URL: http://download.eclipse.org/objectteams/updates/contrib Select and install : JDT Null Annotation Checker (Early Access) Object Teams Equinox Integration
The largest problem is that there it no knowing over the null behavior of the Java API.
The lack of annotated libraries continues to be a problem with Eclipse's built in nullness cehcking.
Another nullness-checking tool is the Checker Framework, which ships with thousands of annotated APIs from the JDK. The Checker Framework also does more accurate checking. Eclipse and FindBugs are bug detectors that find some null pointer errors, but the Checker Framework is a verifier that gives a guarantee of no null pointer errors.
The Checker Framework has an Eclipse plugin. Eclipse' built-in nullness checking has slicker IDE integration, but you can use the Checker Framework Eclipse plugin if you want more powerful checking.
来源：https://stackoverflow.com/questions/7659637/is-there-a-good-eclipse-plugin-for-checking-nonnull-and-nullable-annotations