Often developers face permgen and out of memory issues while running applications on integrated WLS. Most of the time the reason is low memory assigned to JVM for the JDeveloper IDE. On Windows platform to start JDeveloper with good memory setting you can create a launch script (a .cmd) file and use it to launch JDeveloper as explained here.
set USER_MEM_ARGS=-Xms256m -Xmx1024m -XX:MaxPermSize=1024m -XX:CompileThreshold=8000
Please note that the launch script provided on the above link will only help in avoiding JDeveloper memory issues. If you face similar issues during the server start or deployment then you need to change the memory arguments in the setDomainEnv.cmd (located in MW_HOME\bin directory) as well. You need to change following parameters:
set MEM_ARGS_32BIT=-Xms32M -Xmx512M set MEM_MAX_PERM_SIZE_32BIT=-XX:MaxPermSize=1024M
Here, Xms argument enforces the minimum memory heap size and Xmx indicates the maximum memory heap size. MaxPermSize parameter is for the things that do not change very often for example, java classes which are generated at the time of deployment. PermSize is separate from the memory heap size so permGen errors are not fixed if heap memory is increased. Some details on the general JVM properties can be found here.