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1. Open the library project context menu and choose Properties:
Context Menu Preview
2. Select Java Build Path and choose Libraries tab:
3. Choose Add External JARs… and browse to the location on the JAR file.
4. Select the file and choose Open.
The JAR file is added to the list of JARs.
5. Choose OK to continue.
The JAR is added to the project.
Making Reference to the JAR File