Since this method is static, one particular difference will be the fact that the first argument won't be a "this" pointer, but other than that it'll look similar to what we saw with the HelloWorld constructor. The first opcode, "getstatic", fetches a static field and pushes its value onto the stack, which in this case is the "System.out" reference, described by constant pool entry #2 and displayed in the javap comment after the opcode. Next, we load the constant string "Hello, world!", stored in constant pool entry #3. With both of those references on the stack, we "invokevirtual" the PrintStream.println(String[]) method; since it expects one argument (plus the initial "this" reference on which to invoke the method), both of those items we just pushed onto the stack are consumed, and since println() returns nothing (again, as described by the "V" at the end of the signature), nothing is left on the stack when we're finished. A simple "return" opcode terminates the method, and we're done.
Java Virtual Machine Jon Meyer Pdf 12
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