edu.emory.mathcs.util.concurrent.atomic
Class AtomicReferenceArray

java.lang.Object
  |
  +--edu.emory.mathcs.util.concurrent.atomic.AtomicReferenceArray
All Implemented Interfaces:
java.io.Serializable

public class AtomicReferenceArray
extends java.lang.Object
implements java.io.Serializable

An array of object references in which elements may be updated atomically. See the java.util.concurrent.atomic package specification for description of the properties of atomic variables.

Since:
1.5
See Also:
Serialized Form

Constructor Summary
AtomicReferenceArray(int length)
          Create a new AtomicReferenceArray of given length.
AtomicReferenceArray(java.lang.Object[] array)
          Create a new AtomicReferenceArray with the same length as, and all elements copied from, the given array.
 
Method Summary
 boolean compareAndSet(int i, java.lang.Object expect, java.lang.Object update)
          Atomically set the value to the given updated value if the current value == the expected value.
 java.lang.Object get(int i)
          Get the current value at position i.
 java.lang.Object getAndSet(int i, java.lang.Object newValue)
          Set the element at position i to the given value and return the old value.
 int length()
          Returns the length of the array.
 void set(int i, java.lang.Object newValue)
          Set the element at position i to the given value.
 java.lang.String toString()
          Returns the String representation of the current values of array.
 boolean weakCompareAndSet(int i, java.lang.Object expect, java.lang.Object update)
          Atomically set the value to the given updated value if the current value == the expected value.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

AtomicReferenceArray

public AtomicReferenceArray(int length)
Create a new AtomicReferenceArray of given length.

Parameters:
length - the length of the array

AtomicReferenceArray

public AtomicReferenceArray(java.lang.Object[] array)
Create a new AtomicReferenceArray with the same length as, and all elements copied from, the given array.

Parameters:
array - the array to copy elements from
Throws:
java.lang.NullPointerException - if array is null
Method Detail

length

public final int length()
Returns the length of the array.

Returns:
the length of the array

get

public final java.lang.Object get(int i)
Get the current value at position i.

Parameters:
i - the index
Returns:
the current value

set

public final void set(int i,
                      java.lang.Object newValue)
Set the element at position i to the given value.

Parameters:
i - the index
newValue - the new value

getAndSet

public final java.lang.Object getAndSet(int i,
                                        java.lang.Object newValue)
Set the element at position i to the given value and return the old value.

Parameters:
i - the index
newValue - the new value
Returns:
the previous value

compareAndSet

public final boolean compareAndSet(int i,
                                   java.lang.Object expect,
                                   java.lang.Object update)
Atomically set the value to the given updated value if the current value == the expected value.

Parameters:
i - the index
expect - the expected value
update - the new value
Returns:
true if successful. False return indicates that the actual value was not equal to the expected value.

weakCompareAndSet

public final boolean weakCompareAndSet(int i,
                                       java.lang.Object expect,
                                       java.lang.Object update)
Atomically set the value to the given updated value if the current value == the expected value. May fail spuriously.

Parameters:
i - the index
expect - the expected value
update - the new value
Returns:
true if successful.

toString

public java.lang.String toString()
Returns the String representation of the current values of array.

Overrides:
toString in class java.lang.Object
Returns:
the String representation of the current values of array.