Class LDC

java.lang.Object

org.apache.bcel.generic.Instruction

org.apache.bcel.generic.CPInstruction

org.apache.bcel.generic.LDC

All Implemented Interfaces:

Cloneable, ExceptionThrower, IndexedInstruction, PushInstruction, StackProducer, TypedInstruction

Direct Known Subclasses:

LDC_W

public class LDC
extends CPInstruction
implements PushInstruction, ExceptionThrower

LDC - Push item from constant pool.

Stack: ... -> ..., item

Field Summary

Fields inherited from class CPInstruction

index

Modifier and Type	Field	Description
protected int	index	Deprecated. (since 6.0) will be made private; do not access directly, use getter/setter

Fields inherited from class Instruction

length, opcode

Modifier and Type	Field	Description
protected short	length	Deprecated. (since 6.0) will be made private; do not access directly, use getter/setter
protected short	opcode	Deprecated. (since 6.0) will be made private; do not access directly, use getter/setter

Constructor Summary

Constructors

Constructor	Description
LDC(int index)	Constructs an LDC instruction.

Method Summary

Modifier and Type	Method	Description
void	accept(Visitor v)	Call corresponding visitor method(s).
void	dump(DataOutputStream out)	Dumps instruction as byte code to stream out.
Class<?>[]	getExceptions()	Gets the exceptions that may be thrown by this instruction.
Type	getType(ConstantPoolGen cpg)	Gets the type associated with this instruction.
Object	getValue(ConstantPoolGen cpg)	Gets the constant value from the constant pool.
protected void	initFromFile(ByteSequence bytes, boolean wide)	Reads needed data (for example index) from file.
final void	setIndex(int index)	Sets the index to constant pool and adjust size.
protected final void	setSize()	Sets the opcode and length to accommodate the constant pool index.

Methods inherited from class CPInstruction

getIndex, toString, toString

Modifier and Type	Method	Description
final int	getIndex()	Gets the constant pool index referred to by this instruction.
String	toString(boolean verbose)	Long output format: <name of opcode> "["<opcode number>"]" "("<length of instruction>")" "<"< constant pool index>">"
String	toString(ConstantPool cp)	Gets the mnemonic for instruction with symbolic references resolved.

Methods inherited from class Instruction

consumeStack, copy, equals, getComparator, getLength, getName, getOpcode, hashCode, isValidByte, isValidShort, produceStack, readInstruction, setComparator, toString

Modifier and Type	Method	Description
int	consumeStack(ConstantPoolGen cpg)	This method also gives right results for instructions whose effect on the stack depends on the constant pool entry they reference.
Instruction	copy()	Use with caution, since 'BranchInstruction's have a 'target' reference which is not copied correctly (only basic types are).
boolean	equals(Object that)	Tests for equality, delegated to comparator
static InstructionComparator	getComparator()	Deprecated. (6.0) use the built in comparator, or wrap this class in another object that implements these methods
int	getLength()	Gets the length (in bytes) of instruction.
String	getName()	Gets the name of instruction, that is, opcode name.
short	getOpcode()	Gets this instruction's opcode.
int	hashCode()	Gets the hashCode of this object.
static boolean	isValidByte(int value)	Tests if the value can fit in a byte (signed).
static boolean	isValidShort(int value)	Tests if the value can fit in a short (signed).
int	produceStack(ConstantPoolGen cpg)	This method also gives right results for instructions whose effect on the stack depends on the constant pool entry they reference.
static Instruction	readInstruction(ByteSequence bytes)	Reads an instruction from (byte code) input stream and return the appropriate object.
static void	setComparator(InstructionComparator c)	Deprecated. (6.0) use the built in comparator, or wrap this class in another object that implements these methods
String	toString()

Methods inherited from class Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface StackProducer

produceStack

Modifier and Type	Method	Description
int	produceStack(ConstantPoolGen cpg)	Gets how many words are produced on stack.

Constructor Details

LDC

public LDC(int index)

Constructs an LDC instruction.

Parameters:

index - index into constant pool.

Method Details

accept

public void accept(Visitor v)

Call corresponding visitor method(s). The order is: Call visitor methods of implemented interfaces first, then call methods according to the class hierarchy in descending order, that is, the most specific visitXXX() call comes last.

Specified by:

accept in class Instruction

Parameters:

v - Visitor object.

dump

public void dump(DataOutputStream out)
          throws IOException

Dumps instruction as byte code to stream out.

Overrides:

dump in class CPInstruction

Parameters:

out - Output stream.

Throws:

IOException - Thrown when an I/O exception of some sort has occurred.

getExceptions

public Class<?>[] getExceptions()

Description copied from interface: ExceptionThrower

Gets the exceptions that may be thrown by this instruction.

Specified by:

getExceptions in interface ExceptionThrower

Returns:

The exceptions that may be thrown by this instruction.

getType

public Type getType(ConstantPoolGen cpg)

Description copied from class: CPInstruction

Gets the type associated with this instruction.

Specified by:

getType in interface TypedInstruction

Overrides:

getType in class CPInstruction

Parameters:

cpg - The constant pool generator.

Returns:

type related with this instruction.

getValue

public Object getValue(ConstantPoolGen cpg)

Gets the constant value from the constant pool.

Parameters:

cpg - constant pool generator.

Returns:

The constant value.

initFromFile

protected void initFromFile(ByteSequence bytes,
 boolean wide)
                     throws IOException

Reads needed data (for example index) from file.

Overrides:

initFromFile in class CPInstruction

Parameters:

bytes - input stream.

wide - wide prefix?.

Throws:

IOException - Thrown if the implementation needs to read data from the file

setIndex

public final void setIndex(int index)

Sets the index to constant pool and adjust size.

Specified by:

setIndex in interface IndexedInstruction

Overrides:

setIndex in class CPInstruction

Parameters:

index - in constant pool.

setSize

protected final void setSize()

Sets the opcode and length to accommodate the constant pool index.