Add External Class File When You Run Java

To add external class file as input,

1. On the eclipse left pane, right click the project folder name
2. Click on Run As and then click on Run Configurations
3. On the left side, you will see your project folder name nest under Java Application
4. Click on your project folder name

How to Add ASM Library Files in Eclipse

1. On the eclipse left pane, right click the project folder name
2. Click on Properties
3. New window will appear.
In a new window, see the left pane,
a. Click on Java Build Path
b. Click on Libraries tab
c. You will see "Add External Jars" on the right side, click on that button
d. Select the asm library jar files.