joeq.Compiler.BytecodeAnalysis
Class Bytecodes.Instruction

java.lang.Object
  joeq.Compiler.BytecodeAnalysis.Bytecodes.Instruction

All Implemented Interfaces:

Serializable, Cloneable

Direct Known Subclasses:

Bytecodes.ACONST_NULL, Bytecodes.ArithmeticInstruction, Bytecodes.ArrayInstruction, Bytecodes.ARRAYLENGTH, Bytecodes.ATHROW, Bytecodes.BIPUSH, Bytecodes.BranchInstruction, Bytecodes.BREAKPOINT, Bytecodes.ConversionInstruction, Bytecodes.CPInstruction, Bytecodes.DCMPG, Bytecodes.DCMPL, Bytecodes.DCONST, Bytecodes.FCMPG, Bytecodes.FCMPL, Bytecodes.FCONST, Bytecodes.ICONST, Bytecodes.LCMP, Bytecodes.LCONST, Bytecodes.LocalVariableInstruction, Bytecodes.MONITORENTER, Bytecodes.MONITOREXIT, Bytecodes.NEWARRAY, Bytecodes.NOP, Bytecodes.RET, Bytecodes.ReturnInstruction, Bytecodes.SIPUSH, Bytecodes.StackInstruction

Enclosing interface:

Bytecodes

public abstract static class Bytecodes.Instruction
extends Object
implements Cloneable, Serializable

See Also:

Serialized Form

Field Summary

protected short	length
protected short	opcode

Constructor Summary

Bytecodes.Instruction(short opcode, short length)

Method Summary

abstract void	accept(Bytecodes.Visitor v) Call corresponding visitor method(s).
int	consumeStack()
Bytecodes.Instruction	copy() Use with caution, since `BranchInstruction's have a `target' reference which is not copied correctly (only basic types are).
void	dump(DataOutputStream out) Dump instruction as byte code to stream out.
int	getLength()
short	getOpcode()
protected void	initFromFile(jq_ConstantPool cp, jwutil.io.ByteSequence bytes, boolean wide) Read needed data (e.g.
int	produceStack()
static Bytecodes.Instruction	readInstruction(jq_ConstantPool cp, jwutil.io.ByteSequence bytes) Read an instruction from (byte code) input stream and return the appropiate object.
String	toString()
String	toString(boolean verbose) Long output format: <name of opcode> "["<opcode number>"]" "("<length of instruction>")"

Methods inherited from class java.lang.Object

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

Field Detail

length

protected short length

opcode

protected short opcode

Constructor Detail

Bytecodes.Instruction

public Bytecodes.Instruction(short opcode,
                             short length)

Method Detail

dump

public void dump(DataOutputStream out)
          throws IOException

Dump instruction as byte code to stream out.

Parameters:

out - Output stream

Throws:

IOException

toString

public String toString(boolean verbose)

Long output format: <name of opcode> "["<opcode number>"]" "("<length of instruction>")"

Parameters:

verbose - long/short format switch

Returns:

mnemonic for instruction

toString

public String toString()

Overrides:

toString in class Object

Returns:

mnemonic for instruction in verbose format

copy

public Bytecodes.Instruction copy()

Use with caution, since `BranchInstruction's have a `target' reference which is not copied correctly (only basic types are). This also applies for `Select' instructions with their multiple branch targets.

Returns:

(shallow) copy of an instruction

See Also:

Bytecodes.BranchInstruction

initFromFile

protected void initFromFile(jq_ConstantPool cp,
                            jwutil.io.ByteSequence bytes,
                            boolean wide)
                     throws IOException

Read needed data (e.g. index) from file.

Parameters:

cp - constant pool of class we are reading

bytes - byte sequence to read from

wide - "wide" instruction flag

Throws:

IOException

readInstruction

public static final Bytecodes.Instruction readInstruction(jq_ConstantPool cp,
                                                          jwutil.io.ByteSequence bytes)
                                                   throws IOException

Read an instruction from (byte code) input stream and return the appropiate object.

Parameters:

cp - constant pool of class we are reading from

bytes - sequence of bytes to read

Returns:

instruction object being read

Throws:

IOException

consumeStack

public int consumeStack()

Returns:

Number of words consumed from stack by this instruction

produceStack

public int produceStack()

Returns:

Number of words produced onto stack by this instruction

getOpcode

public short getOpcode()

Returns:

this instructions opcode

getLength

public int getLength()

Returns:

length (in bytes) of instruction

accept

public abstract void accept(Bytecodes.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, i.e., the most specific visitXXX() call comes last.

Parameters:

v - Visitor object