net.sf.jode.flow
Class TryBlock

java.lang.Object
  net.sf.jode.flow.StructuredBlock
      net.sf.jode.flow.TryBlock

public class TryBlock
extends StructuredBlock

A TryBlock is created for each exception in the ExceptionHandlers attribute.
For each catch block (there may be more than one catch block appending a single try block) and for each finally and each synchronized block such a TryBlock is created. The finally/synchronized-blocks have a null exception type so that they are easily distinguishable from the catch blocks.
A TryBlock may be converted later into a SynchronizedBlock.

Author:

Jochen Hoenicke

See Also:

CatchBlock, FinallyBlock, SynchronizedBlock

Constructor Summary

TryBlock(FlowBlock tryFlow)

Method Summary

void	addCatchBlock(StructuredBlock catchBlock)
boolean	checkJikesArrayClone() A special transformation for try blocks: jikes generate try/catch-blocks for array clone:
boolean	doTransformations() Do simple transformation on the structuredBlock.
void	dumpInstruction(TabbedPrintWriter writer) Print the instruction expressing this structured block.
StructuredBlock[]	getSubBlocks() Returns all sub block of this structured block.
boolean	jumpMayBeChanged() Determines if there is a sub block, that flows through to the end of this block.
VariableStack	mapStackToLocal(VariableStack stack) This does take the instr into account and modifies stack accordingly.
boolean	replaceSubBlock(StructuredBlock oldBlock, StructuredBlock newBlock) Replaces the given sub block with a new block.

Methods inherited from class net.sf.jode.flow.StructuredBlock

appendBlock, checkConsistent, contains, copyJump, dumpSource, fillInGenSet, flowMayBeChanged, getBCELInstructions, getBytecodeInstructions, getDeclarables, getNextBlock, getNextBlock, getNextFlowBlock, getNextFlowBlock, isEmpty, isSingleExit, makeDeclaration, moveJump, needsBraces, prependBlock, propagateUsage, removeBlock, removeJump, removeOnetimeLocals, removePush, replace, setFlowBlock, setJump, setSuccessors, simplify, swapJump, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

TryBlock

public TryBlock(FlowBlock tryFlow)

Method Detail

addCatchBlock

public void addCatchBlock(StructuredBlock catchBlock)

replaceSubBlock

public boolean replaceSubBlock(StructuredBlock oldBlock,
                               StructuredBlock newBlock)

Replaces the given sub block with a new block.

Overrides:

replaceSubBlock in class StructuredBlock

Parameters:

oldBlock - the old sub block.

newBlock - the new sub block.

Returns:

false, if oldBlock wasn't a direct sub block.

getSubBlocks

public StructuredBlock[] getSubBlocks()

Returns all sub block of this structured block.

Overrides:

getSubBlocks in class StructuredBlock

mapStackToLocal

public VariableStack mapStackToLocal(VariableStack stack)

This does take the instr into account and modifies stack accordingly. It then calls super.mapStackToLocal.

Overrides:

mapStackToLocal in class StructuredBlock

Parameters:

stack - the stack before the instruction is called

Returns:

stack the stack afterwards.

dumpInstruction

public void dumpInstruction(TabbedPrintWriter writer)
                     throws IOException

Description copied from class: StructuredBlock

Print the instruction expressing this structured block.

Specified by:

dumpInstruction in class StructuredBlock

Parameters:

writer - The tabbed print writer, where we print to.

Throws:

IOException

jumpMayBeChanged

public boolean jumpMayBeChanged()

Determines if there is a sub block, that flows through to the end of this block. If this returns true, you know that jump is null.

Overrides:

jumpMayBeChanged in class StructuredBlock

Returns:

true, if the jump may be safely changed.

checkJikesArrayClone

public boolean checkJikesArrayClone()

A special transformation for try blocks: jikes generate try/catch-blocks for array clone:

 try {
     PUSH ARRAY.clone()
 } catch (CloneNotSupportedException ex) {
     throw new InternalError(ex.getMessage());
 }
 

which is simply transformed to the content of the try block.

doTransformations

public boolean doTransformations()

Description copied from class: StructuredBlock

Do simple transformation on the structuredBlock.

Overrides:

doTransformations in class StructuredBlock

Returns:

true, if some transformation was done.