How to step into tomcat source?

You can debug Tomcat as a remote Java application.

Here is the steps:

1. Create a Java project and copy Tomcat source files into project's source folder. (You can ignore compile errors.)
2. Open Bootstrap.java and set a breakpoint at main method.

3. Create a CATALINA_BASE/bin/setenv.bat(or .sh) file and put following line into the file.

   set JPDA_OPTS=-agentlib:jdwp=transport=dt_socket,address=8000,server=y,suspend=y

4. Start the Tomcat in debug mode using catalina.bat (or .sh) from command line.

   catalina.bat jpda start

5. From Eclipse, set up a Debug Configuration under Remote Java Application and connect to the Tomcat process. (Run -> Debug Configurations -> Remote Java Application.)

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