Package org.apache.commons.compress.harmony.unpack200.bytecode.forms

Class ByteCodeForm

java.lang.Object

org.apache.commons.compress.harmony.unpack200.bytecode.forms.ByteCodeForm

Direct Known Subclasses:

ByteForm, IincForm, LabelForm, LocalForm, NoArgumentForm, ReferenceForm, ShortForm, VariableInstructionForm

public abstract class ByteCodeForm
extends Object

Field Summary

Fields

Modifier and Type	Field	Description
protected static final ByteCodeForm[]	byteCodeArray
protected static final Map<String,ByteCodeForm>	byteCodesByName
protected static final boolean	WIDENED

Constructor Summary

Constructors

Constructor	Description
ByteCodeForm(int opcode, String name)	Answer a new instance of this class with the specified opcode and name.
ByteCodeForm(int opcode, String name, int[] rewrite)	Answer a new instance of this class with the specified opcode, name, operandType and rewrite

Method Summary

Modifier and Type	Method	Description
protected void	calculateOperandPosition()
int	firstOperandIndex()
void	fixUpByteCodeTargets(ByteCode byteCode, CodeAttribute codeAttribute)	The ByteCodeForm knows how to fix up a bytecode if it needs to be fixed up because it holds a Label bytecode.
static ByteCodeForm	get(int opcode)
String	getName()
int	getOpcode()
int[]	getRewrite()
int[]	getRewriteCopy()
boolean	hasMultipleByteCodes()	This method will answer true if the receiver is a multi-bytecode instruction (such as aload0_putfield_super); otherwise, it will answer false.
boolean	hasNoOperand()
boolean	nestedMustStartClassPool()
int	operandLength()
abstract void	setByteCodeOperands(ByteCode byteCode, OperandManager operandManager, int codeLength)	When passed a byteCode, an OperandTable and a SegmentConstantPool, this method will set the rewrite of the byteCode appropriately.
String	toString()

Methods inherited from class java.lang.Object

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

Field Details

WIDENED

protected static final boolean WIDENED

See Also:

• Constant Field Values

byteCodeArray

protected static final ByteCodeForm[] byteCodeArray

byteCodesByName

protected static final Map<String,ByteCodeForm> byteCodesByName

Constructor Details

ByteCodeForm

public ByteCodeForm(int opcode,
 String name)

Answer a new instance of this class with the specified opcode and name. Assume no rewrite.

Parameters:

opcode - int corresponding to the opcode's value

name - String printable name of the opcode

ByteCodeForm

public ByteCodeForm(int opcode,
 String name,
 int[] rewrite)

Answer a new instance of this class with the specified opcode, name, operandType and rewrite

Parameters:

opcode - int corresponding to the opcode's value

name - String printable name of the opcode

rewrite - int[] Array of ints. Operand positions (which will later be rewritten in ByteCodes) are indicated by -1.

Method Details

get

public static ByteCodeForm get(int opcode)

calculateOperandPosition

protected void calculateOperandPosition()

firstOperandIndex

public int firstOperandIndex()

fixUpByteCodeTargets

public void fixUpByteCodeTargets(ByteCode byteCode,
 CodeAttribute codeAttribute)

The ByteCodeForm knows how to fix up a bytecode if it needs to be fixed up because it holds a Label bytecode.

Parameters:

byteCode - a ByteCode to be fixed up

codeAttribute - a CodeAttribute used to determine how the ByteCode should be fixed up.

getName

public String getName()

getOpcode

public int getOpcode()

getRewrite

public int[] getRewrite()

getRewriteCopy

public int[] getRewriteCopy()

hasMultipleByteCodes

public boolean hasMultipleByteCodes()

This method will answer true if the receiver is a multi-bytecode instruction (such as aload0_putfield_super); otherwise, it will answer false.

Returns:

boolean true if multibytecode, false otherwise

hasNoOperand

public boolean hasNoOperand()

nestedMustStartClassPool

public boolean nestedMustStartClassPool()

operandLength

public int operandLength()

setByteCodeOperands

public abstract void setByteCodeOperands(ByteCode byteCode,
 OperandManager operandManager,
 int codeLength)

When passed a byteCode, an OperandTable and a SegmentConstantPool, this method will set the rewrite of the byteCode appropriately.

Parameters:

byteCode - ByteCode to be updated (!)

operandManager - OperandTable from which to draw info

codeLength - Length of bytes (excluding this bytecode) from the beginning of the method. Used in calculating padding for some variable-length bytecodes (such as lookupswitch, tableswitch).

toString

public String toString()

Overrides:

toString in class Object