org.apache.commons.pool
Class BaseKeyedObjectPool<K,V>

java.lang.Object
  extended by org.apache.commons.pool.BaseKeyedObjectPool<K,V>
Type Parameters:
K - the type of keys in this pool
V - the type of objects held in this pool
All Implemented Interfaces:
KeyedObjectPool<K,V>
Direct Known Subclasses:
GenericKeyedObjectPool, StackKeyedObjectPool

public abstract class BaseKeyedObjectPool<K,V>
extends java.lang.Object
implements KeyedObjectPool<K,V>

A simple base implementation of KeyedObjectPool. Optional operations are implemented to either do nothing, return a value indicating it is unsupported or throw UnsupportedOperationException.

Since:
Pool 1.0
Version:
$Revision: 1222396 $ $Date: 2011-12-22 14:02:25 -0500 (Thu, 22 Dec 2011) $
Author:
Rodney Waldhoff, Sandy McArthur

Constructor Summary
BaseKeyedObjectPool()
           
 
Method Summary
 void addObject(K key)
          Not supported in this base implementation.
abstract  V borrowObject(K key)
          Obtains an instance from this pool for the specified key.
 void clear()
          Not supported in this base implementation.
 void clear(K key)
          Not supported in this base implementation.
 void close()
          Close this pool.
 int getNumActive()
          Not supported in this base implementation.
 int getNumActive(K key)
          Not supported in this base implementation.
 int getNumIdle()
          Not supported in this base implementation.
 int getNumIdle(K key)
          Not supported in this base implementation.
abstract  void invalidateObject(K key, V obj)
          Invalidates an object from the pool.
abstract  void returnObject(K key, V obj)
          Return an instance to the pool.
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

BaseKeyedObjectPool

public BaseKeyedObjectPool()
Method Detail

addObject

public void addObject(K key)
               throws java.lang.Exception,
                      java.lang.UnsupportedOperationException
Not supported in this base implementation. Always throws an UnsupportedOperationException, subclasses should override this behavior.

Specified by:
addObject in interface KeyedObjectPool<K,V>
Parameters:
key - ignored
Throws:
java.lang.UnsupportedOperationException
java.lang.Exception - when KeyedPoolableObjectFactory.makeObject(K) fails.
java.lang.IllegalStateException - after KeyedObjectPool.close() has been called on this pool.

borrowObject

public abstract V borrowObject(K key)
                        throws java.lang.Exception
Obtains an instance from this pool for the specified key.

Instances returned from this method will have been either newly created with makeObject or will be a previously idle object and have been activated with activateObject and then validated with validateObject.

By contract, clients must return the borrowed object using returnObject, invalidateObject, or a related method as defined in an implementation or sub-interface, using a key that is equivalent to the one used to borrow the instance in the first place.

The behaviour of this method when the pool has been exhausted is not strictly specified (although it may be specified by implementations). Older versions of this method would return null to indicate exhaustion, newer versions are encouraged to throw a NoSuchElementException.

Specified by:
borrowObject in interface KeyedObjectPool<K,V>
Parameters:
key - the key used to obtain the object
Returns:
an instance from this pool.
Throws:
java.lang.IllegalStateException - after close has been called on this pool
java.lang.Exception - when makeObject throws an exception
java.util.NoSuchElementException - when the pool is exhausted and cannot or will not return another instance

clear

public void clear()
           throws java.lang.Exception,
                  java.lang.UnsupportedOperationException
Not supported in this base implementation.

Specified by:
clear in interface KeyedObjectPool<K,V>
Throws:
java.lang.UnsupportedOperationException
java.lang.Exception

clear

public void clear(K key)
           throws java.lang.Exception,
                  java.lang.UnsupportedOperationException
Not supported in this base implementation.

Specified by:
clear in interface KeyedObjectPool<K,V>
Parameters:
key - ignored
Throws:
java.lang.UnsupportedOperationException
java.lang.Exception

close

public void close()
           throws java.lang.Exception
Close this pool. This affects the behavior of isClosed and assertOpen.

Specified by:
close in interface KeyedObjectPool<K,V>
Throws:
java.lang.Exception

getNumActive

public int getNumActive()
                 throws java.lang.UnsupportedOperationException
Not supported in this base implementation.

Specified by:
getNumActive in interface KeyedObjectPool<K,V>
Returns:
a negative value.
Throws:
java.lang.UnsupportedOperationException - deprecated: when this implementation doesn't support the operation

getNumActive

public int getNumActive(K key)
                 throws java.lang.UnsupportedOperationException
Not supported in this base implementation.

Specified by:
getNumActive in interface KeyedObjectPool<K,V>
Parameters:
key - ignored
Returns:
a negative value.
Throws:
java.lang.UnsupportedOperationException - deprecated: when this implementation doesn't support the operation

getNumIdle

public int getNumIdle()
               throws java.lang.UnsupportedOperationException
Not supported in this base implementation.

Specified by:
getNumIdle in interface KeyedObjectPool<K,V>
Returns:
a negative value.
Throws:
java.lang.UnsupportedOperationException - deprecated: when this implementation doesn't support the operation

getNumIdle

public int getNumIdle(K key)
               throws java.lang.UnsupportedOperationException
Not supported in this base implementation.

Specified by:
getNumIdle in interface KeyedObjectPool<K,V>
Parameters:
key - ignored
Returns:
a negative value.
Throws:
java.lang.UnsupportedOperationException - deprecated: when this implementation doesn't support the operation

invalidateObject

public abstract void invalidateObject(K key,
                                      V obj)
                               throws java.lang.Exception

Invalidates an object from the pool.

By contract, obj must have been obtained using borrowObject using a key that is equivalent to the one used to borrow the Object in the first place.

This method should be used when an object that has been borrowed is determined (due to an exception or other problem) to be invalid.

Specified by:
invalidateObject in interface KeyedObjectPool<K,V>
Parameters:
key - the key used to obtain the object
obj - a borrowed instance to be returned.
Throws:
java.lang.Exception

returnObject

public abstract void returnObject(K key,
                                  V obj)
                           throws java.lang.Exception
Return an instance to the pool. By contract, obj must have been obtained using borrowObject or a related method as defined in an implementation or sub-interface using a key that is equivalent to the one used to borrow the instance in the first place.

Specified by:
returnObject in interface KeyedObjectPool<K,V>
Parameters:
key - the key used to obtain the object
obj - a borrowed instance to be returned.
Throws:
java.lang.Exception


Copyright © 2001-2012 Apache Software Foundation. Documenation generated July 23 2013.