Adding a JAR file as a library

From the workbench menu bar, select File > Import. The Import wizard opens

Select File System, then click Next.

In the Directory field, type or browse to select the directory where the JAR file resides.

In the import selection panes, expand the hierarchy and use the buttons to select the JAR file you want to import.

In the Where Do You Want The Imported Resources To Go? field, type or browse to select a workbench container for the JAR file.

Click Finish when you are done.

You now must add the JAR file to the build class path of any projects that need this library.

Java builder
Build classpath

Adding a JAR file to the build path
Attaching source to a JAR file
Working with build paths
Adding source code as individual files

Java Build Path