java.lang.Object
- 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 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

Constructors
Constructor Description

BaseKeyedObjectPool()

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method	Description
`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
  - borrowObject
```
public abstract V borrowObject(K key)
                        throws 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:
    
    IllegalStateException - after close has been called on this pool
    
    Exception - when makeObject throws an exception
    
    NoSuchElementException - when the pool is exhausted and cannot or will not return another instance
  - returnObject
```
public abstract void returnObject(K key,
                                  V obj)
                           throws 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:
    
    Exception
  - invalidateObject
```
public abstract void invalidateObject(K key,
                                      V obj)
                               throws 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:
    
    Exception
  - addObject
```
public void addObject(K key)
               throws Exception,
                      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:
    
    UnsupportedOperationException
    
    Exception - when KeyedPoolableObjectFactory.makeObject(K) fails.
    
    IllegalStateException - after KeyedObjectPool.close() has been called on this pool.
  - getNumIdle
```
public int getNumIdle(K key)
               throws UnsupportedOperationException
```
    Not supported in this base implementation.
    
    Specified by:
    
    getNumIdle in interface KeyedObjectPool<K,V>
    
    Parameters:
    
    key - ignored
    
    Returns:
    
    a negative value.
    
    Throws:
    
    UnsupportedOperationException - deprecated: when this implementation doesn't support the operation
  - getNumActive
```
public int getNumActive(K key)
                 throws UnsupportedOperationException
```
    Not supported in this base implementation.
    
    Specified by:
    
    getNumActive in interface KeyedObjectPool<K,V>
    
    Parameters:
    
    key - ignored
    
    Returns:
    
    a negative value.
    
    Throws:
    
    UnsupportedOperationException - deprecated: when this implementation doesn't support the operation
  - getNumIdle
```
public int getNumIdle()
               throws UnsupportedOperationException
```
    Not supported in this base implementation.
    
    Specified by:
    
    getNumIdle in interface KeyedObjectPool<K,V>
    
    Returns:
    
    a negative value.
    
    Throws:
    
    UnsupportedOperationException - deprecated: when this implementation doesn't support the operation
  - getNumActive
```
public int getNumActive()
                 throws UnsupportedOperationException
```
    Not supported in this base implementation.
    
    Specified by:
    
    getNumActive in interface KeyedObjectPool<K,V>
    
    Returns:
    
    a negative value.
    
    Throws:
    
    UnsupportedOperationException - deprecated: when this implementation doesn't support the operation
  - clear
```
public void clear()
           throws Exception,
                  UnsupportedOperationException
```
    Not supported in this base implementation.
    
    Specified by:
    
    clear in interface KeyedObjectPool<K,V>
    
    Throws:
    
    UnsupportedOperationException
    
    Exception
  - clear
```
public void clear(K key)
           throws Exception,
                  UnsupportedOperationException
```
    Not supported in this base implementation.
    
    Specified by:
    
    clear in interface KeyedObjectPool<K,V>
    
    Parameters:
    
    key - ignored
    
    Throws:
    
    UnsupportedOperationException
    
    Exception
  - close
```
public void close()
           throws Exception
```
    Close this pool. This affects the behavior of isClosed and assertOpen.
    
    Specified by:
    
    close in interface KeyedObjectPool<K,V>
    
    Throws:
    
    Exception

Class BaseKeyedObjectPool<K,​V>

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

BaseKeyedObjectPool

Method Detail

borrowObject

returnObject

invalidateObject

addObject

getNumIdle

getNumActive

getNumIdle

getNumActive

clear

clear

close

Class BaseKeyedObjectPool<K,V>