The procedures correspond to static methods and local variables to local java variables. This constant pool is a table of structures representing various string constants, class names, field names, etc. Our tools will save us from worrying about the detailed structure of constant pool entries. In our case, these will hold information about the global variables of the W program. Instruction Summary A Java virtual machine instruction consists of a one-byte opcode specifying the operation to be performed, followed by zero or more operands supplying arguments or data that are used by the operation.
Many instructions have no operands and consist only of an opcode.
Each method that is invoked, causes the creation of a new frame. The frame contains an array of local variables for the method, and an operand stack where most of the work is done. The first items in the local variable array are the parameters of the method. The remaining elements of the array are the variables declared locally in the method. These variables are accessed by their index in the array.