edu.umd.cs.findbugs.ba

Class BlockTypeAnalysis

java.lang.Object

edu.umd.cs.findbugs.ba.BasicAbstractDataflowAnalysis<BlockType>

edu.umd.cs.findbugs.ba.BlockTypeAnalysis

All Implemented Interfaces:

DataflowAnalysis<BlockType>

public class BlockTypeAnalysis
extends BasicAbstractDataflowAnalysis<BlockType>

Dataflow analysis to determine the nesting of catch and finally blocks within a method.

Author:

David Hovemeyer

See Also:

BlockType

Constructor Summary

Constructors

Constructor and Description
BlockTypeAnalysis(DepthFirstSearch dfs) Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
void	copy(BlockType source, BlockType dest) Copy dataflow facts.
BlockType	createFact() Create empty (uninitialized) dataflow facts for one program point.
BlockOrder	getBlockOrder(CFG cfg) Return the BlockOrder specifying the order in which BasicBlocks should be visited in the main dataflow loop.
void	initEntryFact(BlockType result) Initialize the "entry" fact for the graph.
boolean	isForwards() Returns true if the analysis is forwards, false if backwards.
boolean	isTop(BlockType fact) Is the given fact the top value.
void	makeFactTop(BlockType fact) Make given fact the top value.
void	meetInto(BlockType fact, Edge edge, BlockType result) Meet a dataflow fact associated with an incoming edge into another fact.
boolean	same(BlockType fact1, BlockType fact2) Are given dataflow facts the same?
void	transfer(BasicBlock basicBlock, org.apache.bcel.generic.InstructionHandle end, BlockType start, BlockType result) Transfer function for the analysis.

Methods inherited from class edu.umd.cs.findbugs.ba.BasicAbstractDataflowAnalysis

edgeTransfer, factToString, finishIteration, getFactAfterLocation, getFactAtLocation, getFactOnEdge, getLastUpdateTimestamp, getResultFact, getStartFact, resultFactIterator, setLastUpdateTimestamp, startIteration

Methods inherited from class java.lang.Object

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

Constructor Detail

BlockTypeAnalysis

public BlockTypeAnalysis(DepthFirstSearch dfs)

Constructor.

Parameters:

dfs - a DepthFirstSearch for the method to be analyzed

Method Detail

createFact

public BlockType createFact()

Description copied from interface: DataflowAnalysis

Create empty (uninitialized) dataflow facts for one program point. A valid value will be copied into it before it is used.

copy

public void copy(BlockType source,
        BlockType dest)

Description copied from interface: DataflowAnalysis

Copy dataflow facts.

initEntryFact

public void initEntryFact(BlockType result)
                   throws DataflowAnalysisException

Description copied from interface: DataflowAnalysis

Initialize the "entry" fact for the graph.

Throws:

DataflowAnalysisException

makeFactTop

public void makeFactTop(BlockType fact)

Description copied from interface: DataflowAnalysis

Make given fact the top value.

isTop

public boolean isTop(BlockType fact)

Description copied from interface: DataflowAnalysis

Is the given fact the top value.

isForwards

public boolean isForwards()

Description copied from interface: DataflowAnalysis

Returns true if the analysis is forwards, false if backwards.

getBlockOrder

public BlockOrder getBlockOrder(CFG cfg)

Description copied from interface: DataflowAnalysis

Return the BlockOrder specifying the order in which BasicBlocks should be visited in the main dataflow loop.

Parameters:

cfg - the CFG upon which we're performing dataflow analysis

same

public boolean same(BlockType fact1,
           BlockType fact2)

Description copied from interface: DataflowAnalysis

Are given dataflow facts the same?

transfer

public void transfer(BasicBlock basicBlock,
            @CheckForNull
            org.apache.bcel.generic.InstructionHandle end,
            BlockType start,
            BlockType result)
              throws DataflowAnalysisException

Description copied from interface: DataflowAnalysis

Transfer function for the analysis. Taking dataflow facts at start (which might be either the entry or exit of the block, depending on whether the analysis is forwards or backwards), modify result to be the facts at the other end of the block.

Parameters:

basicBlock - the basic block

end - if nonnull, stop before considering this instruction; otherwise, consider all of the instructions in the basic block

start - dataflow facts at beginning of block (if forward analysis) or end of block (if backwards analysis)

result - resulting dataflow facts at other end of block

Throws:

DataflowAnalysisException

meetInto

public void meetInto(BlockType fact,
            Edge edge,
            BlockType result)
              throws DataflowAnalysisException

Description copied from interface: DataflowAnalysis

Meet a dataflow fact associated with an incoming edge into another fact. This is used to determine the start fact for a basic block.

Parameters:

fact - the predecessor fact (incoming edge)

edge - the edge from the predecessor

result - the result fact

Throws:

DataflowAnalysisException