Local Variable Array in JVM stack

java

Local Variable Array in JVM stack

Unlike static method, for non-static method the first local varaible is always this. For example, here is a piece of code:

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public class LocalVariableDemo {
    
    public static void staticFoo() {
        int i = 1;
    }

    public void foo() {
        int i = 1;
    }

}

And we compile this file into class file and then disassemble the class file:

local_variable_array

As shown, in the static method staticFoo, JVM stores the constant 1 into local varaible array at index 0, while in the non-static method foo, it stores at index 1. The value at index 0 is this, which means this foo method belongs to one certain instance.