With Hot Method Replace, you can modify your source code while debugging without restarting the application or server.
To enable hot method replace for WebSphere® Application Servers started from within IBM® Rational® Software Development Platform: In the Overview tab for the server editor, ensure that the Enable hot method replace in debug mode check box is selected.
To enable hot method replace when starting WebSphere Application Servers from outside IBM Rational Software Development Platform:
When debugging applications on WebSphere Application Server using hot method replace, there are some limitations. To learn about these limitations, see the WebSphere Application Server debug limitations topic.