I want a tool which will see my java code or eclipse java project and convert it into diagrams which show relations and dependencies between classes and methods. Such a tool would greatly reduce the need to explain my code to others. It will make the relevant diagrams/pictures which are much easier to understand than only comments and java docs.
Are there any reliable tools for such purposes ? I prefer free/open source tools. But, anything is okay as long as its accepted by the industry.
EDIT
I need all possible diagrams that one can think of - UML, Sequence, State, Interaction, Show which method calls which, etc. Its not a problem if each functionality is provided by a different tool. I can use multiple tools to generate different types of diagrams.