Package edu.umd.cs.findbugs.ba

Class LockSet

  • public final class LockSet
extends java.lang.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:
    ValueNumberAnalysis

    • Field Summary

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

    • Constructor Summary

      Constructors 
      Constructor Description
      LockSet()
      Constructor.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      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.
      java.util.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.
      java.lang.String toString()  

      • Methods inherited from class java.lang.Object

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

    • Field Detail

      • BOTTOM

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

    • Constructor Detail

      • LockSet

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

    • Method Detail

      • 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 java.lang.String toString()
        Overrides:
        toString in class java.lang.Object

      • getLockedValueNumbers

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