org.zmpp.vm
Class Short1Instruction

java.lang.Object
  org.zmpp.vm.AbstractInstruction
      org.zmpp.vm.Short1Instruction

All Implemented Interfaces:

Instruction

public class Short1Instruction
extends AbstractInstruction

This class represents instructions of type SHORT, 1OP.

Version:

1.0

Author:

Wei-ju Wu

Nested Class Summary

Nested classes/interfaces inherited from class org.zmpp.vm.AbstractInstruction

AbstractInstruction.InstructionForm, AbstractInstruction.OperandCount

Field Summary

static int	OP_DEC
static int	OP_GET_CHILD
static int	OP_GET_PARENT
static int	OP_GET_PROP_LEN
static int	OP_GET_SIBLING
static int	OP_INC
static int	OP_JUMP
static int	OP_JZ List of opcodes.
static int	OP_LOAD
static int	OP_NOT
static int	OP_PRINT_ADDR
static int	OP_PRINT_OBJ
static int	OP_PRINT_PADDR
static int	OP_REMOVE_OBJ
static int	OP_RET

Fields inherited from class org.zmpp.vm.AbstractInstruction

FALSE, TRUE

Constructor Summary

Short1Instruction(Machine machineState, int opcode)
Constructor.

Method Summary

void	execute() Execute the instruction.
AbstractInstruction.InstructionForm	getInstructionForm() Returns the instruction's form.
AbstractInstruction.OperandCount	getOperandCount() Returns the instruction's operand count type.
boolean	isBranch() Returns true, if this instruction is a branch, false, otherwise.
boolean	storesResult() Returns true, if this instruction stores a result, false, otherwise.

Methods inherited from class org.zmpp.vm.AbstractInstruction

addOperand, branchIfTrue, branchOnTest, getBranchOffset, getLength, getMachine, getNumOperands, getOpcode, getOperand, getStoreVariable, getUnsignedValue, getValue, nextInstruction, returnFromRoutine, setBranchIfTrue, setBranchOffset, setLength, setOpcode, setStoreVariable, storeResult, throwInvalidOpcode

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

OP_JZ

public static final int OP_JZ

List of opcodes. See Z-Machine Standards document 1.0 for explanations.

See Also:

Constant Field Values

OP_GET_SIBLING

public static final int OP_GET_SIBLING

See Also:

Constant Field Values

OP_GET_CHILD

public static final int OP_GET_CHILD

See Also:

Constant Field Values

OP_GET_PARENT

public static final int OP_GET_PARENT

See Also:

Constant Field Values

OP_GET_PROP_LEN

public static final int OP_GET_PROP_LEN

See Also:

Constant Field Values

OP_INC

public static final int OP_INC

See Also:

Constant Field Values

OP_DEC

public static final int OP_DEC

See Also:

Constant Field Values

OP_PRINT_ADDR

public static final int OP_PRINT_ADDR

See Also:

Constant Field Values

OP_REMOVE_OBJ

public static final int OP_REMOVE_OBJ

See Also:

Constant Field Values

OP_PRINT_OBJ

public static final int OP_PRINT_OBJ

See Also:

Constant Field Values

OP_RET

public static final int OP_RET

See Also:

Constant Field Values

OP_JUMP

public static final int OP_JUMP

See Also:

Constant Field Values

OP_PRINT_PADDR

public static final int OP_PRINT_PADDR

See Also:

Constant Field Values

OP_LOAD

public static final int OP_LOAD

See Also:

Constant Field Values

OP_NOT

public static final int OP_NOT

See Also:

Constant Field Values

Constructor Detail

Short1Instruction

public Short1Instruction(Machine machineState,
                         int opcode)

Constructor.

Parameters:

machineState - a reference to the MachineState object

opcode - the instruction's opcode

Method Detail

execute

public void execute()

Execute the instruction.

getInstructionForm

public AbstractInstruction.InstructionForm getInstructionForm()

Returns the instruction's form.

Specified by:

getInstructionForm in class AbstractInstruction

Returns:

the instruction form

getOperandCount

public AbstractInstruction.OperandCount getOperandCount()

Returns the instruction's operand count type.

Specified by:

getOperandCount in class AbstractInstruction

Returns:

the operand count type

storesResult

public boolean storesResult()

Returns true, if this instruction stores a result, false, otherwise.

Overrides:

storesResult in class AbstractInstruction

Returns:

true if a result is stored, false otherwise

isBranch

public boolean isBranch()

Returns true, if this instruction is a branch, false, otherwise.

Overrides:

isBranch in class AbstractInstruction

Returns:

true if branch, false otherwise