Java.lang.OutOfMemoryError: Java heap space in Maven

javamavenout-of-memory

When I run maven test, java.lang.OutOfMemoryError happens. I googled it for solutions and have tried to export MAVEN_OPTS=-Xmx1024m, but it did not work.
Anyone know other solutions for this problem? I am using maven 3.0

Paste the error message here when run mvn test -e

Failed tests:
  warning(junit.framework.TestSuite$1)
  testDefaultPigJob_1(com.snda.dw.pig.impl.DefaultPigJobLocalTest)
  testDefaultPigJob_2(com.snda.dw.pig.impl.DefaultPigJobLocalTest)

Tests run: 11, Failures: 3, Errors: 0, Skipped: 0

10/11/01 13:37:18 INFO executionengine.HExecutionEngine: Connecting to hadoop fi
le system at: file:///
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 30.063s
[INFO] Finished at: Mon Nov 01 13:37:18 PDT 2010
[INFO] Final Memory: 3M/6M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-surefire-plugin:2.
5:test (default-test) on project dw.pig: There are test failures.
[ERROR]
[ERROR] Please refer to E:\Code\Java\workspace\dw.pig\target\surefire-reports fo
r the individual test results.
[ERROR] -> [Help 1]
org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal o
rg.apache.maven.plugins:maven-surefire-plugin:2.5:test (default-test) on project
 dw.pig: There are test failures.

Please refer to E:\Code\Java\workspace\dw.pig\target\surefire-reports for the in
dividual test results.
        at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor
.java:199)
        at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor
.java:148)
        at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor
.java:140)
        at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProje
ct(LifecycleModuleBuilder.java:84)
        at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProje
ct(LifecycleModuleBuilder.java:59)
        at org.apache.maven.lifecycle.internal.LifecycleStarter.singleThreadedBu
ild(LifecycleStarter.java:183)
        at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(Lifecycl
eStarter.java:161)
        at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:314)
        at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:151)
        at org.apache.maven.cli.MavenCli.execute(MavenCli.java:445)
        at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:168)
        at org.apache.maven.cli.MavenCli.main(MavenCli.java:132)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.
java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAcces
sorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Laun
cher.java:290)
        at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.jav
a:230)
        at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(La
uncher.java:409)
        at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:
352)
Caused by: org.apache.maven.plugin.MojoFailureException: There are test failures
.

Please refer to E:\Code\Java\workspace\dw.pig\target\surefire-reports for the in
dividual test results.
        at org.apache.maven.plugin.surefire.SurefirePlugin.execute(SurefirePlugi
n.java:629)
        at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(Default
BuildPluginManager.java:107)
        at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor
.java:195)
        ... 19 more
[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/MojoFailureExc

Best Answer

When I run maven test, java.lang.OutOfMemoryError happens. I google it for solutions and have tried to export MAVEN_OPTS=-Xmx1024m, but it did not work.

Setting the Xmx options using MAVEN_OPTS does work, it does configure the JVM used to start Maven. That being said, the maven-surefire-plugin forks a new JVM by default, and your MAVEN_OPTS are thus not passed.

To configure the sizing of the JVM used by the maven-surefire-plugin, you would either have to:

change the forkMode to never (which is be a not so good idea because Maven won't be isolated from the test) ~or~
use the argLine parameter (the right way):

In the later case, something like this:

<configuration>
  <argLine>-Xmx1024m</argLine>
</configuration>

But I have to say that I tend to agree with Stephen here, there is very likely something wrong with one of your test and I'm not sure that giving more memory is the right solution to "solve" (hide?) your problem.

References

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Hashtable does not allow null keys or values. HashMap allows one null key and any number of null values.
One of HashMap's subclasses is LinkedHashMap, so in the event that you'd want predictable iteration order (which is insertion order by default), you could easily swap out the HashMap for a LinkedHashMap. This wouldn't be as easy if you were using Hashtable.

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It goes like this:

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Best Answer

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