Search code examples
javajvmoverridingjvm-arguments

Xbooting a Java class

Basically I want to replace the Canvas class at runtime by an application that uses my custom Canvas class, I heard xbooting can do this but there are no tutorials or anything.

So I'm just wondering what the vm arguments are, can you help me please?

Solution

  • By xboooting you probably mean the -Xbootclasspath parameter?

    You can use the -Xbootclasspath to override the classes that are being loaded when the VM is booting. This way you can give the VM your own implementation of a certain class and it will be used right from the start of the VM. You can do something like this:

    java -Xbootclasspath/p:path_to_the_jar_with_myCanvas_class.jar HelloWorld.class

    But the -Xbootclasspath won't replace the Canvas class at runtime, the replacement will occur already at the start of the VM.

    Here is a nice post about Xbootclasspath : When to use -Xbootclasspath on HotSpot?