BaseObjectPool (Apache Commons Object Pooling Package)

java.lang.Object
- org.apache.commons.pool.BaseObjectPool<T>

Type Parameters:

T - the type of objects held in this pool

All Implemented Interfaces:

ObjectPool<T>

Direct Known Subclasses:

GenericObjectPool, SoftReferenceObjectPool, StackObjectPool
```
public abstract class BaseObjectPool<T>
extends Object
implements ObjectPool<T>
```
A simple base implementation of ObjectPool. 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 and Description

BaseObjectPool()

Constructors
Constructor and Description
`BaseObjectPool()`

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`addObject()` Not supported in this base implementation.
`abstract T`	`borrowObject()` Obtains an instance from the pool.
`void`	`clear()` Not supported in this base implementation.
`void`	`close()` Close this pool.
`int`	`getNumActive()` Not supported in this base implementation.
`int`	`getNumIdle()` Not supported in this base implementation.
`abstract void`	`invalidateObject(T obj)` Invalidates an object from the pool.
`boolean`	`isClosed()` Has this pool instance been closed.
`abstract void`	`returnObject(T obj)` Returns an instance to the pool.

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - BaseObjectPool
```
public BaseObjectPool()
```
- Method Detail
  - addObject
```
public void addObject()
               throws Exception,
                      UnsupportedOperationException
```
    Not supported in this base implementation. Always throws an UnsupportedOperationException, subclasses should override this behavior.
    
    Specified by:
    
    addObject in interface ObjectPool<T>
    
    Throws:
    
    UnsupportedOperationException
    
    Exception - when PoolableObjectFactory.makeObject() fails.
    
    IllegalStateException - after ObjectPool.close() has been called on this pool.
  - borrowObject
```
public abstract T borrowObject()
                        throws Exception
```
    Obtains an instance from the pool.
    
    Specified by:
    
    borrowObject in interface ObjectPool<T>
    
    Returns:
    
    an instance from the pool
    
    Throws:
    
    Exception - if an instance cannot be obtained from the pool
  - clear
```
public void clear()
           throws Exception,
                  UnsupportedOperationException
```
    Not supported in this base implementation.
    
    Specified by:
    
    clear in interface ObjectPool<T>
    
    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 ObjectPool<T>
    
    Throws:
    
    Exception - deprecated: implementations should silently fail if not all resources can be freed.
  - getNumActive
```
public int getNumActive()
                 throws UnsupportedOperationException
```
    Not supported in this base implementation.
    
    Specified by:
    
    getNumActive in interface ObjectPool<T>
    
    Returns:
    
    a negative value.
    
    Throws:
    
    UnsupportedOperationException
  - getNumIdle
```
public int getNumIdle()
               throws UnsupportedOperationException
```
    Not supported in this base implementation.
    
    Specified by:
    
    getNumIdle in interface ObjectPool<T>
    
    Returns:
    
    a negative value.
    
    Throws:
    
    UnsupportedOperationException
  - invalidateObject
```
public abstract void invalidateObject(T obj)
                               throws Exception
```
    Invalidates an object from the pool.
    
    By contract, obj must have been obtained using borrowObject.
    
    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 ObjectPool<T>
    
    Parameters:
    
    obj - a borrowed instance to be disposed.
    
    Throws:
    
    Exception
  - isClosed
```
public final boolean isClosed()
```
    Has this pool instance been closed.
    
    Returns:
    
    true when this pool has been closed.
  - returnObject
```
public abstract void returnObject(T obj)
                           throws Exception
```
    Returns an instance to the pool.
    
    Specified by:
    
    returnObject in interface ObjectPool<T>
    
    Parameters:
    
    obj - instance to return to the pool
    
    Throws:
    
    Exception

Class BaseObjectPool<T>

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

BaseObjectPool

Method Detail

addObject

borrowObject

clear

close

getNumActive

getNumIdle

invalidateObject

isClosed

returnObject