WindowBuilder is a tool that can be used to create graphical user interface (GUI) components in the Eclipse IDE. To install WindowBuilder on Eclipse, you can follow these steps:
Start Eclipse and go to the Help menu.
Click on Install New Software.
In the Work with field, enter the URL for the WindowBuilder update site, depending on your version of Eclipse:
For Eclipse 4.8 (Photon) or later: http://download.eclipse.org/windowbuilder/latest/
For Eclipse 4.7 (Oxygen) or earlier: http://download.eclipse.org/windowbuilder/WB/release/
Click Add.
In the Name field, enter a name for the update site (e.g. "WindowBuilder").
Select the WindowBuilder component and click Next.
Follow the prompts to accept the terms of the license agreement and complete the installation.
Restart Eclipse when prompted.
After installation, you can create a new GUI component by going to the File menu and selecting New > Other. In the New dialog, select the WindowBuilder category and the type of component you want to create (e.g. Swing Designer > JFrame).
For more information on installing WindowBuilder on Eclipse, you can refer to the WindowBuilder documentation.