postorder traversalwhich is exactly the algorithm the jvm uses we described that algorithm in recursive wayhowevernot in way that explicitly uses an operand stack neverthelessthis recursive description is equivalent to nonrecursive version based on using an operand stack implementing recursion one of the benefits of using stack to implement method invocation is that it allows programs to use recursion that isit allows method to call itselfas discussed in section interestinglyearly programming languagessuch as cobol and fortrandid not originally use run-time stacks to implement method and procedure calls but because of the elegance and efficiency that recursion allowsall modern programming languagesincluding the modern versions of classic languages like cobol and fortranutilize run-time stack for method and procedure calls in the execution of recursive methodeach box of the recursion trace corresponds to frame of the java method stack alsothe content of the java method stack corresponds to the chain of boxes from the initial method invocation to the current one to better illustrate how run-time stack allows for recursive methodslet us consider java implementation of the classic recursive definition of the factorial functionnn( )( as shown in code fragment code fragment recursive method factorial the first time we call method factorialits stack frame includes local variable storing the value method factorial(recursively calls itself to compute ( )!which pushes new frame on the java run-time stack in turnthis recursive invocation calls itself to compute ( )!etc the chain of