I don\'t get the exact method to do this. I want a method not for a single project for all projects in eclipse. Please tell me how to solve this problem.
This is for a jar on your classpath in Eclipse, where you have
attached a javadoc zip which Eclipse for some reason dislikes.
NOT attached a valid source jar.
The easiest way is to right-click the jar in question (in the referenced jars, not the physical jar) and choose Preferences -> Javadoc. Here give a correct location (zip/URL) to the correct javadoc. Remember to use the "Validate" button to ensure that it is correctly set up.