how to import .jar lib files

When using Eclipse, first go to the workspace, then to the current project and then create a new folder called 'lib'. Before doing this, select the jar files from the lib folder of the application (Eg: C:\Documents and Settings\grad-cri\My Documents\NetBeansProjects\JavaLibrary1\lib\jfreechart-1.0.10\jfreechart-1.0.10\lib). And then copy-paste these files in the lib folder in the current project. Now using 'Configure build path' you 'Add JAR' files.
Now, all set.