2.11. Instruction Set 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.

Ignoring exceptions, the inner loop of a Java Virtual Machine interpreter is effectively

do {     atomically calculate pc and fetch opcode at pc;     if (operands) fetch operands;     execute the action for the opcode; } while (there is more to do);

The number and size of the operands are determined by the opcode. If an operand is more than one byte in size, then it is stored in big-endian order - high-order byte first. For example, an unsigned 16-bit ...

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