Java.lang.OutOfMemoryError: Java heap space with NetBeans

heap-memoryjavanetbeansout-of-memorytomcat

This is the error I get when I run my web application in an instance of the Tomcat servlet container started by NetBeans. To fix this I even changed the heap size in netbeans.conf, but still it shows the same error. How can I keep this from happening?

HTTP Status 500 - 

--------------------------------------------------------------------------------

type Exception report

message 

description The server encountered an internal error () that prevented it from fulfilling this request.

exception 

javax.servlet.ServletException: Servlet execution threw an exception
    org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:362)


root cause 

java.lang.OutOfMemoryError: Java heap space

note The full stack trace of the root cause is available in the Apache Tomcat/5.5.9 logs.

Best Solution

Changing the heap size in netbeans.conf only changes the heap for NetBeans itself, not for applications run through NetBeans.

The correct way is to right-click on the project and select "Properties" and then "Run"; there you can set the VM options appropriately (-Xmx256m, for instance). It should look something like this:

setting the heap size
(Thanks to VonC for finding this picture.)

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