Package edu.umd.cs.findbugs.ba

Class LockSet

java.lang.Object
edu.umd.cs.findbugs.ba.LockSet
public final class LockSet extends Object
Lock counts for values (as produced by ValueNumberAnalysis). A LockSet tells us the lock counts for all values in a method, insofar as we can accurately determine them.
Author:
David Hovemeyer
See Also:

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final int
    BOTTOM
    An invalid lock count resulting from the meet of two different (inconsistent) lock counts.
    static final int
    TOP
    An uninitialized lock value.

  • Constructor Summary

    Constructors
    Constructor
    Description
    LockSet()
    Constructor.

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    clear()
    Clear all entries out of this LockSet.
    boolean
    containsReturnValue(ValueNumberFactory factory)
    Determine whether or not this lock set contains any locked values which are method return values.
    void
    copyFrom(LockSet other)
    Make this LockSet the same as the given one.
    int
    getLockCount(int valueNumber)
    Get the lock count for given lock object.
    Collection<ValueNumber>
    getLockedValueNumbers(ValueNumberFrame frame)
     
    int
    getNumLockedObjects()
    Get the number of distinct lock values with positive lock counts.
    void
    intersectWith(LockSet other)
    Destructively intersect this lock set with another.
    boolean
    isEmpty()
    Return whether or not this lock set is empty, meaning that no locks have a positive lock count.
    boolean
    isTop()
     
    void
    meetWith(LockSet other)
    Meet this LockSet with another LockSet, storing the result in this object.
    boolean
    sameAs(LockSet other)
    Return whether or not this LockSet is the same as the one given.
    void
    setDefaultLockCount(int defaultLockCount)
    Set the default lock count to return for nonexistent lock entries.
    void
    setLockCount(int valueNumber, int lockCount)
    Set the lock count for a lock object.
    String
    toString()
     

    Methods inherited from class java.lang.Object

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

  • Field Details

    • TOP

      public static final int TOP
      An uninitialized lock value.
      See Also:

    • BOTTOM

      public static final int BOTTOM
      An invalid lock count resulting from the meet of two different (inconsistent) lock counts.
      See Also:

  • Constructor Details

    • LockSet

      public LockSet()
      Constructor. Creates an empty lock set which returns TOP for nonexistent lock entries.

  • Method Details

    • getLockCount

      public int getLockCount(int valueNumber)
      Get the lock count for given lock object.
      Parameters:
      valueNumber - value number of the lock object
      Returns:
      the lock count for the lock object

    • isTop

      public boolean isTop()

    • setLockCount

      public void setLockCount(int valueNumber, int lockCount)
      Set the lock count for a lock object.
      Parameters:
      valueNumber - value number of the lock object
      lockCount - the lock count for the lock

    • setDefaultLockCount

      public void setDefaultLockCount(int defaultLockCount)
      Set the default lock count to return for nonexistent lock entries.
      Parameters:
      defaultLockCount - the default lock count value

    • getNumLockedObjects

      public int getNumLockedObjects()
      Get the number of distinct lock values with positive lock counts.

    • copyFrom

      public void copyFrom(LockSet other)
      Make this LockSet the same as the given one.
      Parameters:
      other - the LockSet to copy

    • clear

      public void clear()
      Clear all entries out of this LockSet.

    • meetWith

      public void meetWith(LockSet other)
      Meet this LockSet with another LockSet, storing the result in this object.
      Parameters:
      other - the other LockSet

    • sameAs

      public boolean sameAs(LockSet other)
      Return whether or not this LockSet is the same as the one given.
      Parameters:
      other - the other LockSet

    • containsReturnValue

      public boolean containsReturnValue(ValueNumberFactory factory)
      Determine whether or not this lock set contains any locked values which are method return values.
      Parameters:
      factory - the ValueNumberFactory that produced the lock values

    • intersectWith

      public void intersectWith(LockSet other)
      Destructively intersect this lock set with another. Note that this is not a dataflow merge: we are interested in finding out which locks are held in both sets, not in the exact lock counts.
      Parameters:
      other - the other LockSet

    • isEmpty

      public boolean isEmpty()
      Return whether or not this lock set is empty, meaning that no locks have a positive lock count.
      Returns:
      true if no locks are held, false if at least one lock is held

    • toString

      public String toString()
      Overrides:
      toString in class Object

    • getLockedValueNumbers

      public Collection<ValueNumber> getLockedValueNumbers(ValueNumberFrame frame)
      Parameters:
      frame -
      Returns:
      a set of the locked value numbers