Frequently Asked Questions for JDT.
- Java Development in Eclipse - The Official Eclipse FAQs
- Java Development Tools - IRC FAQ
The navigation bar is called Breadcrumb, to disable the breadcrumb invoke Toggle Java Editor Breadcrumb in the toolbar or press Alt+Shift+B in the Java editor. More details on the Java editor breadcrumb can be found in Eclipse help.
- Java Development Tool API - The Official Eclipse FAQs
If your question is not answered above
Consider browsing through the frequently asked questions on Stackoverflow
- FAQs on Stackoverflow - Questions with tag jdt
- FAQs on Stackoverflow - Questions with tag eclipse-jdt
Ask a question on the Official JDT forum, however search for topics that might be related before asking!