By debugging of Liferay Portal, that is tomcat application, eclipse make usual stop at ThreadPoolExecutor$Worker.run() line: 912
although I don\'t set a breakpoint
You can fix this immediately by opening the Markers view and delete the Java Exception Breakpoints.
However, to permanently remove this type of breakpoints, you have to go to the Java Debug options and uncheck the "Suspend excecution on uncaught exceptions" option. Then this type of breakpoints won't get added again in the future.