Systems, methods and computer program products are provided for debugging markup language source code of JSP files via Java class files generated therefrom. A Java class file is subjected to introspection to locate a source file specifier that identifies the filename of a Java source file from which the Java class file was compiled. The Java class file is also subjected to introspection to identify one or more source-to-bytecode tables associated with the Java class file. Identified source-to-bytecode tables are modified to include information provided within the comments of the Java source file source code to link respective portions of the Java source code with respective portions of the markup language source code of the JSP file. The located source file specifier is modified to indicate the JSP file as the source file from which the Java class file is compiled.