java.lang.OutOfMemoryError: PermGen space

java.lang.OutOfMemoryError: PermGen space

Problem :

We come across this common exception when starting STS Eclipse or trying to compile java classes through maven command.

Exception I Encountered Was :

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[ERROR] PermGen space -> [Help 1]
java.lang.OutOfMemoryError: PermGen space
        at java.lang.ClassLoader.defineClass1(Native Method)
        at java.lang.ClassLoader.defineClassCond(ClassLoader.java:631)
        at java.lang.ClassLoader.defineClass(ClassLoader.java:615)
        at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:14
1)
        at java.net.URLClassLoader.defineClass(URLClassLoader.java:283)
        at java.net.URLClassLoader.access$000(URLClassLoader.java:58)
        at java.net.URLClassLoader$1.run(URLClassLoader.java:197)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
        at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClassFromSelf(Cl
assRealm.java:389)
        at org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy.loadClass(
SelfFirstStrategy.java:42)
        at org.codehaus.plexus.classworlds.realm.ClassRealm.unsynchronizedLoadCl
ass(ClassRealm.java:259)
        at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm
.java:242)
        at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm
.java:227)
        at java.lang.ClassLoader.defineClass1(Native Method)
        at java.lang.ClassLoader.defineClassCond(ClassLoader.java:631)
        at java.lang.ClassLoader.defineClass(ClassLoader.java:615)
        at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:14
1)
        at java.net.URLClassLoader.defineClass(URLClassLoader.java:283)
        at java.net.URLClassLoader.access$000(URLClassLoader.java:58)
        at java.net.URLClassLoader$1.run(URLClassLoader.java:197)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
        at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClassFromSelf(Cl
assRealm.java:389)
        at org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy.loadClass(
SelfFirstStrategy.java:42)
        at org.codehaus.plexus.classworlds.realm.ClassRealm.unsynchronizedLoadCl
ass(ClassRealm.java:259)
        at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm
.java:242)
        at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm
.java:227)
        at org.apache.maven.plugin.jar.AbstractJarMojo.createArchive(AbstractJar
Mojo.java:202)
        at org.apache.maven.plugin.jar.AbstractJarMojo.execute(AbstractJarMojo.j
ava:255)
        at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(Default
BuildPluginManager.java:106)
        at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor
.java:208)
[ERROR]
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please rea
d the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/OutOfMemoryErr
or

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Solution :

This exception was caused when i was starting the Eclipse for the very first time and also while i was using the mvn compile command to compile the java classes. To resolve this exception i increased the memory size in command prompt before restarting eclipse and increasing the memory in maven options. See below for the examples.

Example :

- Follow the above steps outlined and you should be able to resolve it :


1)Add this to command line JVM before starting tomcat server : -XX:+CMSClassUnloadingEnabled -XX:+CMSPermGenSweepingEnabled
2)For Maven options use this : set MAVEN_OPTS=-Xmx512m -XX:MaxPermSize=128m

This should resolve the above exceptions.

Similar Exception :

     

- java.lang.OutOfMemoryError: PermGen space