org.apache.commons.pool.impl
Class GenericObjectPool

java.lang.Object
  |
  +--org.apache.commons.pool.BaseObjectPool
        |
        +--org.apache.commons.pool.impl.GenericObjectPool

All Implemented Interfaces:

ObjectPool

public class GenericObjectPool

extends BaseObjectPool

implements ObjectPool

A configurable ObjectPool implementation.

When coupled with the appropriate PoolableObjectFactory, GenericObjectPool provides robust pooling functionality for arbitrary objects.

A GenericObjectPool provides a number of configurable parameters:

• maxActive controls the maximum number of objects that can be borrowed from the pool at one time. When non-positive, there is no limit to the number of objects that may be active at one time. When maxActive is exceeded, the pool is said to be exhausted.
• maxIdle controls the maximum number of objects that can sit idle in the pool at any time. When non-positive, there is no limit to the number of objects that may be idle at one time.
• whenExhaustedAction specifies the behaviour of the borrowObject() method when the pool is exhausted:
  • When whenExhaustedAction is WHEN_EXHAUSTED_FAIL, borrowObject() will throw a NoSuchElementException
  • When whenExhaustedAction is WHEN_EXHAUSTED_GROW, borrowObject() will create a new object and return it(essentially making maxActive meaningless.)
  • When whenExhaustedAction is WHEN_EXHAUSTED_BLOCK, borrowObject() will block (invoke Object.wait(long) until a new or idle object is available. If a positive maxWait value is supplied, the borrowObject() will block for at most that many milliseconds, after which a NoSuchElementException will be thrown. If maxWait is non-positive, the borrowObject() method will block indefinitely.
• When testOnBorrow is set, the pool will attempt to validate each object before it is returned from the borrowObject() method. (Using the provided factory's PoolableObjectFactory.validateObject(java.lang.Object) method.) Objects that fail to validate will be dropped from the pool, and a different object will be borrowed.
• When testOnReturn is set, the pool will attempt to validate each object before it is returned to the pool in the returnObject(java.lang.Object) method. (Using the provided factory's PoolableObjectFactory.validateObject(java.lang.Object) method.) Objects that fail to validate will be dropped from the pool.

Optionally, one may configure the pool to examine and possibly evict objects as they sit idle in the pool. This is performed by an "idle object eviction" thread, which runs asychronously. The idle object eviction thread may be configured using the following attributes:

• timeBetweenEvictionRunsMillis indicates how long the eviction thread should sleep before "runs" of examining idle objects. When non-positive, no eviction thread will be launched.
• minEvictableIdleTimeMillis specifies the minimum amount of time that an object may sit idle in the pool before it is eligable for eviction due to idle time. When non-positive, no object will be dropped from the pool due to idle time alone.
• testWhileIdle indicates whether or not idle objects should be validated using the factory's PoolableObjectFactory.validateObject(java.lang.Object) method. Objects that fail to validate will be dropped from the pool.

Version:

$Revision: 1.6 $ $Date: 2002/08/10 21:13:26 $

Author:

Rodney Waldhoff

See Also:

GenericKeyedObjectPool

Nested Class Summary

static class

GenericObjectPool.Config A simple "struct" encapsulating the configuration information for a GenericObjectPool.

Field Summary

static int	DEFAULT_MAX_ACTIVE The default cap on the total number of active instances from the pool.
static int	DEFAULT_MAX_IDLE The default cap on the number of "sleeping" instances in the pool.
static long	DEFAULT_MAX_WAIT The default maximum amount of time (in millis) the borrowObject() method should block before throwing an exception when the pool is exhausted and the "when exhausted" action is WHEN_EXHAUSTED_BLOCK.
static long	DEFAULT_MIN_EVICTABLE_IDLE_TIME_MILLIS The default value for getMinEvictableIdleTimeMillis().
static int	DEFAULT_NUM_TESTS_PER_EVICTION_RUN The default number of objects to examine per run in the idle object evictor.
static boolean	DEFAULT_TEST_ON_BORROW The default "test on borrow" value.
static boolean	DEFAULT_TEST_ON_RETURN The default "test on return" value.
static boolean	DEFAULT_TEST_WHILE_IDLE The default "test while idle" value.
static long	DEFAULT_TIME_BETWEEN_EVICTION_RUNS_MILLIS The default "time between eviction runs" value.
static byte	DEFAULT_WHEN_EXHAUSTED_ACTION The default "when exhausted action" for the pool.
static byte	WHEN_EXHAUSTED_BLOCK A "when exhausted action" type indicating that when the pool is exhausted (i.e., the maximum number of active objects has been reached), the borrowObject() method should block until a new object is available, or the maximum wait time has been reached.
static byte	WHEN_EXHAUSTED_FAIL A "when exhausted action" type indicating that when the pool is exhausted (i.e., the maximum number of active objects has been reached), the borrowObject() method should fail, throwing a NoSuchElementException.
static byte	WHEN_EXHAUSTED_GROW A "when exhausted action" type indicating that when the pool is exhausted (i.e., the maximum number of active objects has been reached), the borrowObject() method should simply create a new object anyway.

Constructor Summary

GenericObjectPool(PoolableObjectFactory factory)
Create a new GenericObjectPool using the specified values.

GenericObjectPool(PoolableObjectFactory factory, GenericObjectPool.Config config)
Create a new GenericObjectPool using the specified values.

GenericObjectPool(PoolableObjectFactory factory, int maxActive)
Create a new GenericObjectPool using the specified values.

GenericObjectPool(PoolableObjectFactory factory, int maxActive, byte whenExhaustedAction, long maxWait)
Create a new GenericObjectPool using the specified values.

GenericObjectPool(PoolableObjectFactory factory, int maxActive, byte whenExhaustedAction, long maxWait, boolean testOnBorrow, boolean testOnReturn)
Create a new GenericObjectPool using the specified values.

GenericObjectPool(PoolableObjectFactory factory, int maxActive, byte whenExhaustedAction, long maxWait, int maxIdle)
Create a new GenericObjectPool using the specified values.

GenericObjectPool(PoolableObjectFactory factory, int maxActive, byte whenExhaustedAction, long maxWait, int maxIdle, boolean testOnBorrow, boolean testOnReturn)
Create a new GenericObjectPool using the specified values.

GenericObjectPool(PoolableObjectFactory factory, int maxActive, byte whenExhaustedAction, long maxWait, int maxIdle, boolean testOnBorrow, boolean testOnReturn, long timeBetweenEvictionRunsMillis, int numTestsPerEvictionRun, long minEvictableIdleTimeMillis, boolean testWhileIdle)
Create a new GenericObjectPool using the specified values.

Method Summary

Object	borrowObject() Obtain an instance from my pool.
void	clear() Clears any objects sitting idle in the pool, releasing any associated resources (optional operation).
void	close() Close this pool, and free any resources associated with it.
int	getMaxActive() Returns the cap on the total number of active instances from my pool.
int	getMaxIdle() Returns the cap on the number of "idle" instances in the pool.
long	getMaxWait() Returns the maximum amount of time (in milliseconds) the borrowObject() method should block before throwing an exception when the pool is exhausted and the "when exhausted" action is WHEN_EXHAUSTED_BLOCK.
long	getMinEvictableIdleTimeMillis() Returns the minimum amount of time an object may sit idle in the pool before it is eligable for eviction by the idle object evictor (if any).
int	getNumActive() Return the number of instances currently borrowed from my pool (optional operation).
int	getNumIdle() Return the number of instances currently idle in my pool (optional operation).
int	getNumTestsPerEvictionRun() Returns the number of objects to examine during each run of the idle object evictor thread (if any).
boolean	getTestOnBorrow() When true, objects will be validated before being returned by the borrowObject() method.
boolean	getTestOnReturn() When true, objects will be validated before being returned to the pool within the returnObject(java.lang.Object).
boolean	getTestWhileIdle() When true, objects will be validated by the idle object evictor (if any).
long	getTimeBetweenEvictionRunsMillis() Returns the number of milliseconds to sleep between runs of the idle object evictor thread.
byte	getWhenExhaustedAction() Returns the action to take when the borrowObject() method is invoked when the pool is exhausted (the maximum number of "active" objects has been reached).
void	returnObject(Object obj) Return an instance to my pool.
void	setConfig(GenericObjectPool.Config conf) Sets my configuration.
void	setFactory(PoolableObjectFactory factory) Sets the factory I use to create new instances (optional operation).
void	setMaxActive(int maxActive) Sets the cap on the total number of active instances from my pool.
void	setMaxIdle(int maxIdle) Sets the cap on the number of "idle" instances in the pool.
void	setMaxWait(long maxWait) Sets the maximum amount of time (in milliseconds) the borrowObject() method should block before throwing an exception when the pool is exhausted and the "when exhausted" action is WHEN_EXHAUSTED_BLOCK.
void	setMinEvictableIdleTimeMillis(long minEvictableIdleTimeMillis) Sets the minimum amount of time an object may sit idle in the pool before it is eligable for eviction by the idle object evictor (if any).
void	setNumTestsPerEvictionRun(int numTestsPerEvictionRun) Sets the number of objects to examine during each run of the idle object evictor thread (if any).
void	setTestOnBorrow(boolean testOnBorrow) When true, objects will be validated before being returned by the borrowObject() method.
void	setTestOnReturn(boolean testOnReturn) When true, objects will be validated before being returned to the pool within the returnObject(java.lang.Object).
void	setTestWhileIdle(boolean testWhileIdle) When true, objects will be validated by the idle object evictor (if any).
void	setTimeBetweenEvictionRunsMillis(long timeBetweenEvictionRunsMillis) Sets the number of milliseconds to sleep between runs of the idle object evictor thread.
void	setWhenExhaustedAction(byte whenExhaustedAction) Sets the action to take when the borrowObject() method is invoked when the pool is exhausted (the maximum number of "active" objects has been reached).

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DEFAULT_MAX_ACTIVE

public static final int DEFAULT_MAX_ACTIVE

The default cap on the total number of active instances from the pool.

See Also:

getMaxActive(), Constant Field Values

DEFAULT_MAX_IDLE

public static final int DEFAULT_MAX_IDLE

The default cap on the number of "sleeping" instances in the pool.

See Also:

getMaxIdle(), setMaxIdle(int), Constant Field Values

DEFAULT_MAX_WAIT

public static final long DEFAULT_MAX_WAIT

The default maximum amount of time (in millis) the borrowObject() method should block before throwing an exception when the pool is exhausted and the "when exhausted" action is WHEN_EXHAUSTED_BLOCK.

See Also:

getMaxWait(), setMaxWait(long), Constant Field Values

DEFAULT_MIN_EVICTABLE_IDLE_TIME_MILLIS

public static final long DEFAULT_MIN_EVICTABLE_IDLE_TIME_MILLIS

The default value for getMinEvictableIdleTimeMillis().

See Also:

getMinEvictableIdleTimeMillis(), setMinEvictableIdleTimeMillis(long), Constant Field Values

DEFAULT_NUM_TESTS_PER_EVICTION_RUN

public static final int DEFAULT_NUM_TESTS_PER_EVICTION_RUN

The default number of objects to examine per run in the idle object evictor.

See Also:

getNumTestsPerEvictionRun(), setNumTestsPerEvictionRun(int), getTimeBetweenEvictionRunsMillis(), setTimeBetweenEvictionRunsMillis(long), Constant Field Values

DEFAULT_TEST_ON_BORROW

public static final boolean DEFAULT_TEST_ON_BORROW

The default "test on borrow" value.

See Also:

getTestOnBorrow(), setTestOnBorrow(boolean), Constant Field Values

DEFAULT_TEST_ON_RETURN

public static final boolean DEFAULT_TEST_ON_RETURN

The default "test on return" value.

See Also:

getTestOnReturn(), setTestOnReturn(boolean), Constant Field Values

DEFAULT_TEST_WHILE_IDLE

public static final boolean DEFAULT_TEST_WHILE_IDLE

The default "test while idle" value.

See Also:

getTestWhileIdle(), setTestWhileIdle(boolean), getTimeBetweenEvictionRunsMillis(), setTimeBetweenEvictionRunsMillis(long), Constant Field Values

DEFAULT_TIME_BETWEEN_EVICTION_RUNS_MILLIS

public static final long DEFAULT_TIME_BETWEEN_EVICTION_RUNS_MILLIS

The default "time between eviction runs" value.

See Also:

getTimeBetweenEvictionRunsMillis(), setTimeBetweenEvictionRunsMillis(long), Constant Field Values

DEFAULT_WHEN_EXHAUSTED_ACTION

public static final byte DEFAULT_WHEN_EXHAUSTED_ACTION

The default "when exhausted action" for the pool.

See Also:

WHEN_EXHAUSTED_BLOCK, WHEN_EXHAUSTED_FAIL, WHEN_EXHAUSTED_GROW, setWhenExhaustedAction(byte), Constant Field Values

WHEN_EXHAUSTED_BLOCK

public static final byte WHEN_EXHAUSTED_BLOCK

A "when exhausted action" type indicating that when the pool is exhausted (i.e., the maximum number of active objects has been reached), the borrowObject() method should block until a new object is available, or the maximum wait time has been reached.

See Also:

WHEN_EXHAUSTED_FAIL, WHEN_EXHAUSTED_GROW, setMaxWait(long), getMaxWait(), setWhenExhaustedAction(byte), Constant Field Values

WHEN_EXHAUSTED_FAIL

public static final byte WHEN_EXHAUSTED_FAIL

A "when exhausted action" type indicating that when the pool is exhausted (i.e., the maximum number of active objects has been reached), the borrowObject() method should fail, throwing a NoSuchElementException.

See Also:

WHEN_EXHAUSTED_BLOCK, WHEN_EXHAUSTED_GROW, setWhenExhaustedAction(byte), Constant Field Values

WHEN_EXHAUSTED_GROW

public static final byte WHEN_EXHAUSTED_GROW

A "when exhausted action" type indicating that when the pool is exhausted (i.e., the maximum number of active objects has been reached), the borrowObject() method should simply create a new object anyway.

See Also:

WHEN_EXHAUSTED_FAIL, WHEN_EXHAUSTED_GROW, setWhenExhaustedAction(byte), Constant Field Values

Constructor Detail

GenericObjectPool

public GenericObjectPool(PoolableObjectFactory factory)

Create a new GenericObjectPool using the specified values.

Parameters:

factory - the (possibly null)PoolableObjectFactory to use to create, validate and destroy objects

GenericObjectPool

public GenericObjectPool(PoolableObjectFactory factory,
                         GenericObjectPool.Config config)

Create a new GenericObjectPool using the specified values.

Parameters:

factory - the (possibly null)PoolableObjectFactory to use to create, validate and destroy objects

config - a non-null GenericObjectPool.Config describing my configuration

GenericObjectPool

public GenericObjectPool(PoolableObjectFactory factory,
                         int maxActive)

Create a new GenericObjectPool using the specified values.

Parameters:

factory - the (possibly null)PoolableObjectFactory to use to create, validate and destroy objects

maxActive - the maximum number of objects that can be borrowed from me at one time (see setMaxActive(int))

GenericObjectPool

public GenericObjectPool(PoolableObjectFactory factory,
                         int maxActive,
                         byte whenExhaustedAction,
                         long maxWait)

Create a new GenericObjectPool using the specified values.

Parameters:

factory - the (possibly null)PoolableObjectFactory to use to create, validate and destroy objects

maxActive - the maximum number of objects that can be borrowed from me at one time (see setMaxActive(int))

whenExhaustedAction - the action to take when the pool is exhausted (see getWhenExhaustedAction())

maxWait - the maximum amount of time to wait for an idle object when the pool is exhausted an and whenExhaustedAction is WHEN_EXHAUSTED_BLOCK (otherwise ignored) (see getMaxWait())

GenericObjectPool

public GenericObjectPool(PoolableObjectFactory factory,
                         int maxActive,
                         byte whenExhaustedAction,
                         long maxWait,
                         boolean testOnBorrow,
                         boolean testOnReturn)

Create a new GenericObjectPool using the specified values.

Parameters:

factory - the (possibly null)PoolableObjectFactory to use to create, validate and destroy objects

maxActive - the maximum number of objects that can be borrowed from me at one time (see setMaxActive(int))

whenExhaustedAction - the action to take when the pool is exhausted (see getWhenExhaustedAction())

maxWait - the maximum amount of time to wait for an idle object when the pool is exhausted an and whenExhaustedAction is WHEN_EXHAUSTED_BLOCK (otherwise ignored) (see getMaxWait())

testOnBorrow - whether or not to validate objects before they are returned by the borrowObject() method (see getTestOnBorrow())

testOnReturn - whether or not to validate objects after they are returned to the returnObject(java.lang.Object) method (see getTestOnReturn())

GenericObjectPool

public GenericObjectPool(PoolableObjectFactory factory,
                         int maxActive,
                         byte whenExhaustedAction,
                         long maxWait,
                         int maxIdle)

Create a new GenericObjectPool using the specified values.

Parameters:

factory - the (possibly null)PoolableObjectFactory to use to create, validate and destroy objects

maxActive - the maximum number of objects that can be borrowed from me at one time (see setMaxActive(int))

whenExhaustedAction - the action to take when the pool is exhausted (see getWhenExhaustedAction())

maxWait - the maximum amount of time to wait for an idle object when the pool is exhausted an and whenExhaustedAction is WHEN_EXHAUSTED_BLOCK (otherwise ignored) (see getMaxWait())

maxIdle - the maximum number of idle objects in my pool (see getMaxIdle())

GenericObjectPool

public GenericObjectPool(PoolableObjectFactory factory,
                         int maxActive,
                         byte whenExhaustedAction,
                         long maxWait,
                         int maxIdle,
                         boolean testOnBorrow,
                         boolean testOnReturn)

Create a new GenericObjectPool using the specified values.

Parameters:

factory - the (possibly null)PoolableObjectFactory to use to create, validate and destroy objects

maxActive - the maximum number of objects that can be borrowed from me at one time (see setMaxActive(int))

whenExhaustedAction - the action to take when the pool is exhausted (see getWhenExhaustedAction())

maxWait - the maximum amount of time to wait for an idle object when the pool is exhausted an and whenExhaustedAction is WHEN_EXHAUSTED_BLOCK (otherwise ignored) (see getMaxWait())

maxIdle - the maximum number of idle objects in my pool (see getMaxIdle())

testOnBorrow - whether or not to validate objects before they are returned by the borrowObject() method (see getTestOnBorrow())

testOnReturn - whether or not to validate objects after they are returned to the returnObject(java.lang.Object) method (see getTestOnReturn())

GenericObjectPool

public GenericObjectPool(PoolableObjectFactory factory,
                         int maxActive,
                         byte whenExhaustedAction,
                         long maxWait,
                         int maxIdle,
                         boolean testOnBorrow,
                         boolean testOnReturn,
                         long timeBetweenEvictionRunsMillis,
                         int numTestsPerEvictionRun,
                         long minEvictableIdleTimeMillis,
                         boolean testWhileIdle)

Create a new GenericObjectPool using the specified values.

Parameters:

factory - the (possibly null)PoolableObjectFactory to use to create, validate and destroy objects

maxActive - the maximum number of objects that can be borrowed from me at one time (see setMaxActive(int))

whenExhaustedAction - the action to take when the pool is exhausted (see setWhenExhaustedAction(byte))

maxWait - the maximum amount of time to wait for an idle object when the pool is exhausted an and whenExhaustedAction is WHEN_EXHAUSTED_BLOCK (otherwise ignored) (see setMaxWait(long))

maxIdle - the maximum number of idle objects in my pool (see setMaxIdle(int))

testOnBorrow - whether or not to validate objects before they are returned by the borrowObject() method (see setTestOnBorrow(boolean))

testOnReturn - whether or not to validate objects after they are returned to the returnObject(java.lang.Object) method (see setTestOnReturn(boolean))

timeBetweenEvictionRunsMillis - the amount of time (in milliseconds) to sleep between examining idle objects for eviction (see setTimeBetweenEvictionRunsMillis(long))

numTestsPerEvictionRun - the number of idle objects to examine per run within the idle object eviction thread (if any) (see setNumTestsPerEvictionRun(int))

minEvictableIdleTimeMillis - the minimum number of milliseconds an object can sit idle in the pool before it is eligable for evcition (see setMinEvictableIdleTimeMillis(long))

testWhileIdle - whether or not to validate objects in the idle object eviction thread, if any (see setTestWhileIdle(boolean))

Method Detail

borrowObject

public Object borrowObject()
                    throws Exception

Description copied from interface: ObjectPool

Obtain an instance from my pool. By contract, clients MUST return the borrowed instance using returnObject or a related method as defined in an implementation or sub-interface.

The behaviour of this method when the pool has been exhausted is not specified (although it may be specified by implementations).

Specified by:

borrowObject in interface ObjectPool

Specified by:

borrowObject in class BaseObjectPool

Returns:

an instance from my pool.

Exception

clear

public void clear()

Description copied from interface: ObjectPool

Clears any objects sitting idle in the pool, releasing any associated resources (optional operation).

Specified by:

clear in interface ObjectPool

Overrides:

clear in class BaseObjectPool

close

public void close()
           throws Exception

Description copied from interface: ObjectPool

Close this pool, and free any resources associated with it.

Specified by:

close in interface ObjectPool

Overrides:

close in class BaseObjectPool

Exception

getMaxActive

public int getMaxActive()

Returns the cap on the total number of active instances from my pool.

Returns:

the cap on the total number of active instances from my pool.

See Also:

setMaxActive(int)

getMaxIdle

public int getMaxIdle()

Returns the cap on the number of "idle" instances in the pool.

Returns:

the cap on the number of "idle" instances in the pool.

See Also:

setMaxIdle(int)

getMaxWait

public long getMaxWait()

Returns the maximum amount of time (in milliseconds) the borrowObject() method should block before throwing an exception when the pool is exhausted and the "when exhausted" action is WHEN_EXHAUSTED_BLOCK. When less than 0, the borrowObject() method may block indefinitely.

See Also:

setMaxWait(long), setWhenExhaustedAction(byte), WHEN_EXHAUSTED_BLOCK

getMinEvictableIdleTimeMillis

public long getMinEvictableIdleTimeMillis()

Returns the minimum amount of time an object may sit idle in the pool before it is eligable for eviction by the idle object evictor (if any).

See Also:

setMinEvictableIdleTimeMillis(long), setTimeBetweenEvictionRunsMillis(long)

getNumActive

public int getNumActive()

Description copied from interface: ObjectPool

Return the number of instances currently borrowed from my pool (optional operation).

Specified by:

getNumActive in interface ObjectPool

Overrides:

getNumActive in class BaseObjectPool

Returns:

the number of instances currently borrowed in my pool

getNumIdle

public int getNumIdle()

Description copied from interface: ObjectPool

Return the number of instances currently idle in my pool (optional operation). This may be considered an approximation of the number of objects that can be borrowed without creating any new instances.

Specified by:

getNumIdle in interface ObjectPool

Overrides:

getNumIdle in class BaseObjectPool

Returns:

the number of instances currently idle in my pool

getNumTestsPerEvictionRun

public int getNumTestsPerEvictionRun()

Returns the number of objects to examine during each run of the idle object evictor thread (if any).

See Also:

setNumTestsPerEvictionRun(int), setTimeBetweenEvictionRunsMillis(long)

getTestOnBorrow

public boolean getTestOnBorrow()

When true, objects will be validated before being returned by the borrowObject() method. If the object fails to validate, it will be dropped from the pool, and we will attempt to borrow another.

See Also:

setTestOnBorrow(boolean)

getTestOnReturn

public boolean getTestOnReturn()

When true, objects will be validated before being returned to the pool within the returnObject(java.lang.Object).

See Also:

setTestOnReturn(boolean)

getTestWhileIdle

public boolean getTestWhileIdle()

When true, objects will be validated by the idle object evictor (if any). If an object fails to validate, it will be dropped from the pool.

See Also:

setTestWhileIdle(boolean), setTimeBetweenEvictionRunsMillis(long)

getTimeBetweenEvictionRunsMillis

public long getTimeBetweenEvictionRunsMillis()

Returns the number of milliseconds to sleep between runs of the idle object evictor thread. When non-positive, no idle object evictor thread will be run.

See Also:

setTimeBetweenEvictionRunsMillis(long)

getWhenExhaustedAction

public byte getWhenExhaustedAction()

Returns the action to take when the borrowObject() method is invoked when the pool is exhausted (the maximum number of "active" objects has been reached).

Returns:

one of WHEN_EXHAUSTED_BLOCK, WHEN_EXHAUSTED_FAIL or WHEN_EXHAUSTED_GROW

See Also:

setWhenExhaustedAction(byte)

returnObject

public void returnObject(Object obj)
                  throws Exception

Description copied from interface: ObjectPool

Return an instance to my pool. By contract, obj MUST have been obtained using borrowObject or a related method as defined in an implementation or sub-interface.

Specified by:

returnObject in interface ObjectPool

Specified by:

returnObject in class BaseObjectPool

Parameters:

obj - a borrowed instance to be returned.

Exception

setConfig

public void setConfig(GenericObjectPool.Config conf)

Sets my configuration.

See Also:

GenericObjectPool.Config

setFactory

public void setFactory(PoolableObjectFactory factory)
                throws IllegalStateException

Description copied from interface: ObjectPool

Sets the factory I use to create new instances (optional operation).

Specified by:

setFactory in interface ObjectPool

Overrides:

setFactory in class BaseObjectPool

Parameters:

factory - the PoolableObjectFactory I use to create new instances.

Throws:

IllegalStateException - when the factory cannot be set at this time

setMaxActive

public void setMaxActive(int maxActive)

Sets the cap on the total number of active instances from my pool.

Parameters:

maxActive - The cap on the total number of active instances from my pool. Use a negative value for an infinite number of instances.

See Also:

getMaxActive()

setMaxIdle

public void setMaxIdle(int maxIdle)

Sets the cap on the number of "idle" instances in the pool.

Parameters:

maxIdle - The cap on the number of "idle" instances in the pool. Use a negative value to indicate an unlimited number of idle instances.

See Also:

getMaxIdle()

setMaxWait

public void setMaxWait(long maxWait)

Sets the maximum amount of time (in milliseconds) the borrowObject() method should block before throwing an exception when the pool is exhausted and the "when exhausted" action is WHEN_EXHAUSTED_BLOCK. When less than 0, the borrowObject() method may block indefinitely.

See Also:

getMaxWait(), setWhenExhaustedAction(byte), WHEN_EXHAUSTED_BLOCK

setMinEvictableIdleTimeMillis

public void setMinEvictableIdleTimeMillis(long minEvictableIdleTimeMillis)

Sets the minimum amount of time an object may sit idle in the pool before it is eligable for eviction by the idle object evictor (if any). When non-positive, no objects will be evicted from the pool due to idle time alone.

See Also:

getMinEvictableIdleTimeMillis(), setTimeBetweenEvictionRunsMillis(long)

setNumTestsPerEvictionRun

public void setNumTestsPerEvictionRun(int numTestsPerEvictionRun)

Sets the number of objects to examine during each run of the idle object evictor thread (if any).

When a negative value is supplied, ceil(BaseObjectPool.numIdle())/abs(getNumTestsPerEvictionRun()) tests will be run. I.e., when the value is -n, roughly one nth of the idle objects will be tested per run.

See Also:

getNumTestsPerEvictionRun(), setTimeBetweenEvictionRunsMillis(long)

setTestOnBorrow

public void setTestOnBorrow(boolean testOnBorrow)

When true, objects will be validated before being returned by the borrowObject() method. If the object fails to validate, it will be dropped from the pool, and we will attempt to borrow another.

See Also:

getTestOnBorrow()

setTestOnReturn

public void setTestOnReturn(boolean testOnReturn)

When true, objects will be validated before being returned to the pool within the returnObject(java.lang.Object).

See Also:

getTestOnReturn()

setTestWhileIdle

public void setTestWhileIdle(boolean testWhileIdle)

When true, objects will be validated by the idle object evictor (if any). If an object fails to validate, it will be dropped from the pool.

See Also:

getTestWhileIdle(), setTimeBetweenEvictionRunsMillis(long)

setTimeBetweenEvictionRunsMillis

public void setTimeBetweenEvictionRunsMillis(long timeBetweenEvictionRunsMillis)

Sets the number of milliseconds to sleep between runs of the idle object evictor thread. When non-positive, no idle object evictor thread will be run.

See Also:

getTimeBetweenEvictionRunsMillis()

setWhenExhaustedAction

public void setWhenExhaustedAction(byte whenExhaustedAction)

Sets the action to take when the borrowObject() method is invoked when the pool is exhausted (the maximum number of "active" objects has been reached).

Parameters:

whenExhaustedAction - the action code, which must be one of WHEN_EXHAUSTED_BLOCK, WHEN_EXHAUSTED_FAIL, or WHEN_EXHAUSTED_GROW

See Also:

getWhenExhaustedAction()