AbstractAnalysis (checker-framework 3.7.0 API)

java.lang.Object
- org.checkerframework.dataflow.analysis.AbstractAnalysis<V,S,T>

Type Parameters:

V - the abstract value type to be tracked by the analysis

S - the store type used in the analysis

T - the transfer function type that is used to approximated runtime behavior

All Implemented Interfaces:

Analysis<V,S,T>

Direct Known Subclasses:

BackwardAnalysisImpl, ForwardAnalysisImpl
```
public abstract class AbstractAnalysis<V extends AbstractValue<V>,S extends Store<S>,T extends TransferFunction<V,S>>
extends Object
implements Analysis<V,S,T>
```
Implementation of common features for BackwardAnalysisImpl and ForwardAnalysisImpl.

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`protected static class`	`AbstractAnalysis.Worklist` A worklist is a priority queue of blocks in which the order is given by depth-first ordering to place non-loop predecessors ahead of successors.

Nested classes/interfaces inherited from interface org.checkerframework.dataflow.analysis.Analysis
Analysis.Direction

Field Summary

Fields
Modifier and Type	Field and Description
`protected @MonotonicNonNull ControlFlowGraph`	`cfg` The current control flow graph to perform the analysis on.
`protected @Nullable TransferInput<V,S>`	`currentInput` The current transfer input when the analysis is running.
`protected @InternedDistinct @Nullable Node`	`currentNode` The node that is currently handled in the analysis (if it is running).
`protected @InternedDistinct @Nullable Tree`	`currentTree` The tree that is currently being looked at.
`protected Analysis.Direction`	`direction` The direction of this analysis.
`protected HashMap<Element,V>`	`finalLocalValues` Map from (effectively final) local variable elements to their abstract value.
`protected IdentityHashMap<Block,TransferInput<V,S>>`	`inputs` The transfer inputs of every basic block (assumed to be 'no information' if not present, inputs before blocks in forward analysis, after blocks in backward analysis).
`protected boolean`	`isRunning` Is the analysis currently running?
`protected IdentityHashMap<Node,V>`	`nodeValues` Abstract values of nodes.
`protected T`	`transferFunction` The transfer function for regular nodes.
`protected AbstractAnalysis.Worklist`	`worklist` The worklist used for the fix-point iteration.

Constructor Summary

Constructors
Modifier	Constructor and Description
`protected`	`AbstractAnalysis(Analysis.Direction direction)` Implementation of common features for `BackwardAnalysisImpl` and `ForwardAnalysisImpl`.

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`protected void`	`addToWorklist(Block b)` Add a basic block to `worklist`.
`protected TransferResult<V,S>`	`callTransferFunction(Node node, TransferInput<V,S> transferInput)` Call the transfer function for node `node`, and set that node as current node first.
`@Nullable ClassTree`	`getContainingClass(Tree t)` Get the `ClassTree` of the current CFG if the argument `Tree` maps to a `Node` in the CFG or `null` otherwise.
`@Nullable MethodTree`	`getContainingMethod(Tree t)` Get the `MethodTree` of the current CFG if the argument `Tree` maps to a `Node` in the CFG or `null` otherwise.
`@Nullable Tree`	`getCurrentTree()` Returns the tree that is currently being looked at.
`Analysis.Direction`	`getDirection()` Get the direction of this analysis.
`S`	`getExceptionalExitStore()` Returns the exceptional exit store.
`@Nullable Set<Node>`	`getNodesForTree(Tree t)` Get the set of `Node`s for a given `Tree`.
`IdentityHashMap<Node,V>`	`getNodeValues()` Returns all current node values.
`S`	`getRegularExitStore()` Returns the regular exit store, or `null`, if there is no such store (because the method cannot exit through the regular exit block).
`AnalysisResult<V,S>`	`getResult()` The result of running the analysis.
`T`	`getTransferFunction()` Get the transfer function of this analysis.
`V`	`getValue(Node n)` Returns the abstract value for `Node` `n`, or `null` if no information is available.
`V`	`getValue(Tree t)` Return the abstract value for `Tree` `t`, or `null` if no information is available.
`protected void`	`init(ControlFlowGraph cfg)` Initialize the analysis with a new control flow graph.
`protected void`	`initFields(ControlFlowGraph cfg)` Initialize class fields based on a given control flow graph.
`protected abstract void`	`initInitialInputs()` Initialize the transfer inputs of every basic block before performing the analysis.
`boolean`	`isRunning()` Is the analysis currently running?
`protected abstract void`	`propagateStoresTo(Block nextBlock, Node node, TransferInput<V,S> currentInput, Store.FlowRule flowRule, boolean addToWorklistAgain)` Propagate the stores in `currentInput` to the next block in the direction of analysis, according to the `flowRule`.
`protected static <S> S`	`readFromStore(Map<Block,S> stores, Block b)` Read the store for a particular basic block from a map of stores (or `null` if none exists yet).
`protected void`	`setCurrentNode(@Nullable Node currentNode)` Set the node that is currently being looked at.
`void`	`setCurrentTree(Tree currentTree)` Set the tree that is currently being looked at.
`protected boolean`	`updateNodeValues(Node node, TransferResult<V,S> transferResult)` Updates the value of node `node` to the value of the `transferResult`.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.checkerframework.dataflow.analysis.Analysis
getInput, performAnalysis, performAnalysisBlock, runAnalysisFor

- Field Detail
  - direction
```
protected final Analysis.Direction direction
```
    The direction of this analysis.
  - isRunning
```
protected boolean isRunning
```
    Is the analysis currently running?
  - transferFunction
```
protected T extends TransferFunction<V,S> transferFunction
```
    The transfer function for regular nodes.
  - cfg
```
protected @MonotonicNonNull ControlFlowGraph cfg
```
    The current control flow graph to perform the analysis on.
  - inputs
```
protected final IdentityHashMap<Block,TransferInput<V extends AbstractValue<V>,S extends Store<S>>> inputs
```
    The transfer inputs of every basic block (assumed to be 'no information' if not present, inputs before blocks in forward analysis, after blocks in backward analysis).
  - worklist
```
protected final AbstractAnalysis.Worklist worklist
```
    The worklist used for the fix-point iteration.
  - nodeValues
```
protected final IdentityHashMap<Node,V extends AbstractValue<V>> nodeValues
```
    Abstract values of nodes.
  - finalLocalValues
```
protected final HashMap<Element,V extends AbstractValue<V>> finalLocalValues
```
    Map from (effectively final) local variable elements to their abstract value.
  - currentNode
```
protected @InternedDistinct @Nullable Node currentNode
```
    The node that is currently handled in the analysis (if it is running). The following invariant holds:
```
   !isRunning ==> (currentNode == null)
 
```
  - currentTree
```
protected @InternedDistinct @Nullable Tree currentTree
```
    The tree that is currently being looked at. The transfer function can set this tree to make sure that calls to getValue will not return information for this given tree.
  - currentInput
```
protected @Nullable TransferInput<V extends AbstractValue<V>,S extends Store<S>> currentInput
```
    The current transfer input when the analysis is running.
- Constructor Detail
  - AbstractAnalysis
```
protected AbstractAnalysis(Analysis.Direction direction)
```
    Implementation of common features for BackwardAnalysisImpl and ForwardAnalysisImpl.
    
    Parameters:
    
    direction - direction of the analysis
- Method Detail
  - getCurrentTree
```
public @Nullable Tree getCurrentTree()
```
    Returns the tree that is currently being looked at. The transfer function can set this tree to make sure that calls to getValue will not return information for this given tree.
    
    Returns:
    
    the tree that is currently being looked at
  - setCurrentTree
```
public void setCurrentTree(@FindDistinct
                           Tree currentTree)
```
    Set the tree that is currently being looked at.
    
    Parameters:
    
    currentTree - the tree that should be currently looked at
  - setCurrentNode
```
protected void setCurrentNode(@FindDistinct
                              @Nullable Node currentNode)
```
    Set the node that is currently being looked at.
    
    Parameters:
    
    currentNode - the node that should be currently looked at
  - initInitialInputs
```
@RequiresNonNull(value="cfg")
protected abstract void initInitialInputs()
```
    Initialize the transfer inputs of every basic block before performing the analysis.
  - propagateStoresTo
```
protected abstract void propagateStoresTo(Block nextBlock,
                                          Node node,
                                          TransferInput<V,S> currentInput,
                                          Store.FlowRule flowRule,
                                          boolean addToWorklistAgain)
```
    Propagate the stores in currentInput to the next block in the direction of analysis, according to the flowRule.
    
    Parameters:
    
    nextBlock - the target block to propagate the stores to
    
    node - the node of the target block
    
    currentInput - the current transfer input
    
    flowRule - the flow rule being used
    
    addToWorklistAgain - whether the block should be added to worklist again
  - isRunning
```
public boolean isRunning()
```
    Description copied from interface: Analysis
    
    Is the analysis currently running?
    
    Specified by:
    
    isRunning in interface Analysis<V extends AbstractValue<V>,S extends Store<S>,T extends TransferFunction<V,S>>
    
    Returns:
    
    true if the analysis is running currently, else false
  - getDirection
```
public Analysis.Direction getDirection()
```
    Description copied from interface: Analysis
    
    Get the direction of this analysis.
    
    Specified by:
    
    getDirection in interface Analysis<V extends AbstractValue<V>,S extends Store<S>,T extends TransferFunction<V,S>>
    
    Returns:
    
    the direction of this analysis
  - getResult
```
@RequiresNonNull(value="cfg")
public AnalysisResult<V,S> getResult()
```
    Description copied from interface: Analysis
    
    The result of running the analysis. This is only available once the analysis finished running.
    
    Specified by:
    
    getResult in interface Analysis<V extends AbstractValue<V>,S extends Store<S>,T extends TransferFunction<V,S>>
    
    Returns:
    
    the result of running the analysis
  - getTransferFunction
```
public T getTransferFunction()
```
    Description copied from interface: Analysis
    
    Get the transfer function of this analysis.
    
    Specified by:
    
    getTransferFunction in interface Analysis<V extends AbstractValue<V>,S extends Store<S>,T extends TransferFunction<V,S>>
    
    Returns:
    
    the transfer function of this analysis
  - getValue
```
public V getValue(Node n)
```
    Description copied from interface: Analysis
    
    Returns the abstract value for Node n, or null if no information is available. Note that if the analysis has not finished yet, this value might not represent the final value for this node.
    
    Specified by:
    
    getValue in interface Analysis<V extends AbstractValue<V>,S extends Store<S>,T extends TransferFunction<V,S>>
    
    Parameters:
    
    n - n a node
    
    Returns:
    
    the abstract value for node n, or null if no information is available
  - getNodeValues
```
public IdentityHashMap<Node,V> getNodeValues()
```
    Returns all current node values.
    
    Returns:
    
    nodeValues
  - getRegularExitStore
```
@RequiresNonNull(value="cfg")
public S getRegularExitStore()
```
    Description copied from interface: Analysis
    
    Returns the regular exit store, or null, if there is no such store (because the method cannot exit through the regular exit block).
    
    Specified by:
    
    getRegularExitStore in interface Analysis<V extends AbstractValue<V>,S extends Store<S>,T extends TransferFunction<V,S>>
    
    Returns:
    
    the regular exit store, or null, if there is no such store (because the method cannot exit through the regular exit block)
  - getExceptionalExitStore
```
@RequiresNonNull(value="cfg")
public S getExceptionalExitStore()
```
    Description copied from interface: Analysis
    
    Returns the exceptional exit store.
    
    Specified by:
    
    getExceptionalExitStore in interface Analysis<V extends AbstractValue<V>,S extends Store<S>,T extends TransferFunction<V,S>>
    
    Returns:
    
    the exceptional exit store
  - getNodesForTree
```
public @Nullable Set<Node> getNodesForTree(Tree t)
```
    Get the set of Nodes for a given Tree. Returns null for trees that don't produce a value.
    
    Parameters:
    
    t - the given tree
    
    Returns:
    
    the set of corresponding nodes to the given tree
  - getValue
```
public V getValue(Tree t)
```
    Description copied from interface: Analysis
    
    Return the abstract value for Tree t, or null if no information is available. Note that if the analysis has not finished yet, this value might not represent the final value for this node.
    
    Specified by:
    
    getValue in interface Analysis<V extends AbstractValue<V>,S extends Store<S>,T extends TransferFunction<V,S>>
    
    Parameters:
    
    t - the given tree
    
    Returns:
    
    the abstract value for the given tree
  - getContainingMethod
```
public @Nullable MethodTree getContainingMethod(Tree t)
```
    Get the MethodTree of the current CFG if the argument Tree maps to a Node in the CFG or null otherwise.
    
    Parameters:
    
    t - the given tree
    
    Returns:
    
    the contained method tree of the given tree
  - getContainingClass
```
public @Nullable ClassTree getContainingClass(Tree t)
```
    Get the ClassTree of the current CFG if the argument Tree maps to a Node in the CFG or null otherwise.
    
    Parameters:
    
    t - the given tree
    
    Returns:
    
    the contained class tree of the given tree
  - callTransferFunction
```
protected TransferResult<V,S> callTransferFunction(Node node,
                                                   TransferInput<V,S> transferInput)
```
    Call the transfer function for node node, and set that node as current node first. This method requires a transferInput that the method can modify.
    
    Parameters:
    
    node - the given node
    
    transferInput - the transfer input
    
    Returns:
    
    the output of the transfer function
  - init
```
protected final void init(ControlFlowGraph cfg)
```
    Initialize the analysis with a new control flow graph.
    
    Parameters:
    
    cfg - the control flow graph to use
  - initFields
```
@EnsuresNonNull(value="this.cfg")
protected void initFields(ControlFlowGraph cfg)
```
    Initialize class fields based on a given control flow graph. Sub-class may override this method to initialize customized fields.
    
    Parameters:
    
    cfg - a given control flow graph
  - updateNodeValues
```
protected boolean updateNodeValues(Node node,
                                   TransferResult<V,S> transferResult)
```
    Updates the value of node node to the value of the transferResult. Returns true if the node's value changed, or a store was updated.
    
    Parameters:
    
    node - the node to update
    
    transferResult - the transfer result being updated
    
    Returns:
    
    true if the node's value changed, or a store was updated
  - readFromStore
```
protected static <S> S readFromStore(Map<Block,S> stores,
                                     Block b)
```
    Read the store for a particular basic block from a map of stores (or null if none exists yet).
    
    Type Parameters:
    
    S - method return type should be a subtype of Store
    
    Parameters:
    
    stores - a map of stores
    
    b - the target block
    
    Returns:
    
    the store for the target block
  - addToWorklist
```
protected void addToWorklist(Block b)
```
    Add a basic block to worklist. If b is already present, the method does nothing.
    
    Parameters:
    
    b - the block to add to worklist

Class AbstractAnalysis<V extends AbstractValue<V>,S extends Store<S>,T extends TransferFunction<V,S>>

Nested Class Summary

Nested classes/interfaces inherited from interface org.checkerframework.dataflow.analysis.Analysis

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface org.checkerframework.dataflow.analysis.Analysis

Field Detail

direction

isRunning

transferFunction

cfg

inputs

worklist

nodeValues

finalLocalValues

currentNode

currentTree

currentInput

Constructor Detail

AbstractAnalysis

Method Detail

getCurrentTree

setCurrentTree

setCurrentNode

initInitialInputs

propagateStoresTo

isRunning

getDirection

getResult

getTransferFunction

getValue

getNodeValues

getRegularExitStore

getExceptionalExitStore

getNodesForTree

getValue

getContainingMethod

getContainingClass

callTransferFunction

init

initFields

updateNodeValues

readFromStore

addToWorklist