Performing builds automatically
  To indicate that you want the Workbench to perform incremental builds whenever resources are saved:
  
    - Open the 
    
 General > Workspace
    preference page. 
    - Select the Build automatically checkbox.
 
    - Click OK to close the Preferences page. The Workbench will automatically perform incremental builds of
    resources modified since the last build. Whenever a resource is modified, another incremental build occurs.
 
  
  Builds
  Performing builds manually
  Changing build order