build a jdk rt.jar with debug option

1)download the src.zip for your jdk 2)unzip src.zip into a tmp/src folder:unzip src.zip -d /src 3)get list of all java class into a file: find -name "*.java* > files.txt 4)compile all java files:javac -verbose -g -d ..\out -J-Xmx2048m -cp c:\jdk7u80\jre\lib\rt.jar;c:\jdk7u80\lib\tools.jar @files.txt 5)create jar file:cd tmp\out; jar cvf rt.jar * 6)copy the rt.jar into jdk\jre\lib\endorsed