Eclipse presses crl+ left mouse button, cannot find the solution of source file.

This situation typically occurs in tomcat because of a lack of source files for the class. It is rare in JDK that the source files from the JDK are loaded into the JDK when they are configured. And Tomcat does not have the class source files, you need to go to the Internet to download separately. So after clicking on the display, such as: Cannot find the source file

1. The solution is to download the Tomcat source file on the Internet and click "Change attached source ..." To find the path to source, as shown in:

2. Select "External Location", click on the Red box "External file" to find the path of the source file you just downloaded, click "Open" to add the src file, such as:

3, the source file path has been found, click on the "OK" can be the class file normal display

Eclipse presses crl+ left mouse button, cannot find the solution of source file.