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| No Format |
|---|
# Do this in your JDK build directory.
# The exploded JDK build:
$ jdk/bin/javac -J-verbose ~/tmp/HelloWorld.java | grep LambdaForm | grep __JVM_LookupDefineClass__
[0.142s][info][class,load] java.lang.invoke.LambdaForm$MH/0x0000000800066c40 source: __JVM_LookupDefineClass__
[0.143s][info][class,load] java.lang.invoke.LambdaForm$DMH/0x0000000800066040 source: __JVM_LookupDefineClass__
[0.143s][info][class,load] java.lang.invoke.LambdaForm$MH/0x0000000800066440 source: __JVM_LookupDefineClass__
[snip]
$ jdk/bin/javac -J-verbose ~/tmp/HelloWorld.java | grep LambdaForm | grep __JVM_LookupDefineClass__ | wc
102 408 11400
# The final JDK image:
$ images/jdk/bin/javac -J-verbose ~/tmp/HelloWorld.java | grep LambdaForm | grep __JVM_LookupDefineClass__ | wc
34 136 3800 |
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We regenerate the XXX$Holder classes to contain all necessary methods used by the application.
Static Dump
This is being has been implemented in JDK-8247536 (Support for pre-generated java.lang.invoke classes in CDS static archive - integrated into JDK 16).
During the trial run (with -XX:DumpLoadedClassList=classlist), we can save the list of LambdaForm handlers using a special syntax like:
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