How to remove launch configuration histories in eclipse?

Question

Right click an arbitrary existing project in Package Explore, choose \"export...\" - \"Java\" - \"Runnable JAR file\", I find all the old projects in the \"launch configuration\

Answer 1

This question seems to be well answered here, however, to make changes I have simply deleted every undesirable launch configuration from the below path.

${WORKSPACE}/.metadata/.plugins/org.eclipse.debug.core/.launches/Delete all the .class LAUNCH Files

After deleting the files, it is necessary to restart Eclipse for the changes to take effect.