Package org.apache.tomcat.dbcp.pool2.impl

Class DefaultPooledObject<T>

java.lang.Object

org.apache.tomcat.dbcp.pool2.impl.DefaultPooledObject<T>

Type Parameters:

T - the type of object in the pool

All Implemented Interfaces:

Comparable<PooledObject<T>>, PooledObject<T>

Direct Known Subclasses:

PooledSoftReference

public class DefaultPooledObject<T>
extends Object
implements PooledObject<T>

This wrapper is used to track the additional information, such as state, for the pooled objects.

This class is intended to be thread-safe.

Since:

2.0

Constructor Summary

Constructors

Constructor	Description
DefaultPooledObject(T object)	Creates a new instance that wraps the provided object so that the pool can track the state of the pooled object.

Method Summary

Modifier and Type	Method	Description
boolean	allocate()	Allocates the object.
int	compareTo(PooledObject<T> other)	Orders instances based on idle time - i.e. the length of time since the instance was returned to the pool.
boolean	deallocate()	Deallocates the object and sets it IDLE if it is currently ALLOCATED or RETURNING.
boolean	endEvictionTest(Deque<PooledObject<T>> idleQueue)	Notifies the object that the eviction test has ended.
long	getActiveTimeMillis()	Gets the amount of time in milliseconds this object last spent in the active state (it may still be active in which case subsequent calls will return an increased value).
long	getBorrowedCount()	Gets the number of times this object has been borrowed.
Instant	getCreateInstant()	Gets the time (using the same basis as Instant.now()) that this object was created.
long	getCreateTime()	Gets the time (using the same basis as Clock.instant()) that this object was created.
Duration	getIdleDuration()	Gets the amount of time that this object last spend in the idle state (it may still be idle in which case subsequent calls will return an increased value).
Duration	getIdleTime()	Gets the amount of time that this object last spend in the idle state (it may still be idle in which case subsequent calls will return an increased value).
long	getIdleTimeMillis()	Gets the amount of time in milliseconds that this object last spend in the idle state (it may still be idle in which case subsequent calls will return an increased value).
Instant	getLastBorrowInstant()	Gets the time the wrapped object was last borrowed.
long	getLastBorrowTime()	Gets the time the wrapped object was last borrowed.
Instant	getLastReturnInstant()	Gets the time the wrapped object was last borrowed.
long	getLastReturnTime()	Gets the time the wrapped object was last returned.
Instant	getLastUsedInstant()	Gets an estimate of the last time this object was used.
long	getLastUsedTime()	Gets an estimate of the last time this object was used.
T	getObject()	Gets the underlying object that is wrapped by this instance of PooledObject.
PooledObjectState	getState()	Gets the state of this object.
void	invalidate()	Sets the state to INVALID.
void	markAbandoned()	Marks the pooled object as ABANDONED.
void	markReturning()	Marks the pooled object as RETURNING.
void	printStackTrace(PrintWriter writer)	Prints the stack trace of the code that borrowed this pooled object and the stack trace of the last code to use this object (if available) to the supplied writer.
void	setLogAbandoned(boolean logAbandoned)	Sets whether to use abandoned object tracking.
void	setRequireFullStackTrace(boolean requireFullStackTrace)	Configures the stack trace generation strategy based on whether or not fully detailed stack traces are required.
boolean	startEvictionTest()	Attempts to place the pooled object in the PooledObjectState.EVICTION state.
String	toString()	Gets a String form of the wrapper for debug purposes.
void	use()	Records the current stack trace as the last time the object was used.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.apache.tomcat.dbcp.pool2.PooledObject

equals, getActiveDuration, getActiveTime, getFullDuration, hashCode

Constructor Details

DefaultPooledObject

public DefaultPooledObject(T object)

Creates a new instance that wraps the provided object so that the pool can track the state of the pooled object.

Parameters:

object - The object to wrap

Method Details

allocate

public boolean allocate()

Allocates the object.

Specified by:

allocate in interface PooledObject<T>

Returns:

true if the original state was IDLE

compareTo

public int compareTo(PooledObject<T> other)

Description copied from interface: PooledObject

Orders instances based on idle time - i.e. the length of time since the instance was returned to the pool. Used by the GKOP idle object evictor.

Note: This class has a natural ordering that is inconsistent with equals if distinct objects have the same identity hash code.

Specified by:

compareTo in interface Comparable<T>

Specified by:

compareTo in interface PooledObject<T>

deallocate

public boolean deallocate()

Deallocates the object and sets it IDLE if it is currently ALLOCATED or RETURNING.

Specified by:

deallocate in interface PooledObject<T>

Returns:

true if the state was ALLOCATED or RETURNING.

endEvictionTest

public boolean endEvictionTest(Deque<PooledObject<T>> idleQueue)

Description copied from interface: PooledObject

Notifies the object that the eviction test has ended.

Specified by:

endEvictionTest in interface PooledObject<T>

Parameters:

idleQueue - The queue of idle objects to which the object should be returned.

Returns:

Currently not used.

getActiveTimeMillis

public long getActiveTimeMillis()

Description copied from interface: PooledObject

Gets the amount of time in milliseconds this object last spent in the active state (it may still be active in which case subsequent calls will return an increased value).

Specified by:

getActiveTimeMillis in interface PooledObject<T>

Returns:

The time in milliseconds last spent in the active state.

getBorrowedCount

public long getBorrowedCount()

Gets the number of times this object has been borrowed.

Specified by:

getBorrowedCount in interface PooledObject<T>

Returns:

The number of times this object has been borrowed.

Since:

2.1

getCreateInstant

public Instant getCreateInstant()

Description copied from interface: PooledObject

Gets the time (using the same basis as Instant.now()) that this object was created.

Specified by:

getCreateInstant in interface PooledObject<T>

Returns:

The creation time for the wrapped object.

getCreateTime

public long getCreateTime()

Description copied from interface: PooledObject

Gets the time (using the same basis as Clock.instant()) that this object was created.

Specified by:

getCreateTime in interface PooledObject<T>

Returns:

The creation time for the wrapped object.

getIdleDuration

public Duration getIdleDuration()

Description copied from interface: PooledObject

Gets the amount of time that this object last spend in the idle state (it may still be idle in which case subsequent calls will return an increased value).

Specified by:

getIdleDuration in interface PooledObject<T>

Returns:

The amount of time in last spent in the idle state.

getIdleTime

public Duration getIdleTime()

Description copied from interface: PooledObject

Gets the amount of time that this object last spend in the idle state (it may still be idle in which case subsequent calls will return an increased value).

Specified by:

getIdleTime in interface PooledObject<T>

Returns:

The amount of time in last spent in the idle state.

getIdleTimeMillis

public long getIdleTimeMillis()

Description copied from interface: PooledObject

Gets the amount of time in milliseconds that this object last spend in the idle state (it may still be idle in which case subsequent calls will return an increased value).

Specified by:

getIdleTimeMillis in interface PooledObject<T>

Returns:

The time in milliseconds last spent in the idle state.

getLastBorrowInstant

public Instant getLastBorrowInstant()

Description copied from interface: PooledObject

Gets the time the wrapped object was last borrowed.

Specified by:

getLastBorrowInstant in interface PooledObject<T>

Returns:

The time the object was last borrowed.

getLastBorrowTime

public long getLastBorrowTime()

Description copied from interface: PooledObject

Gets the time the wrapped object was last borrowed.

Specified by:

getLastBorrowTime in interface PooledObject<T>

Returns:

The time the object was last borrowed.

getLastReturnInstant

public Instant getLastReturnInstant()

Description copied from interface: PooledObject

Gets the time the wrapped object was last borrowed.

Specified by:

getLastReturnInstant in interface PooledObject<T>

Returns:

The time the object was last borrowed.

getLastReturnTime

public long getLastReturnTime()

Description copied from interface: PooledObject

Gets the time the wrapped object was last returned.

Specified by:

getLastReturnTime in interface PooledObject<T>

Returns:

The time the object was last returned.

getLastUsedInstant

public Instant getLastUsedInstant()

Gets an estimate of the last time this object was used. If the class of the pooled object implements TrackedUse, what is returned is the maximum of TrackedUse.getLastUsedInstant() and getLastBorrowTime(); otherwise this method gives the same value as getLastBorrowTime().

Specified by:

getLastUsedInstant in interface PooledObject<T>

Returns:

the last Instant this object was used.

getLastUsedTime

public long getLastUsedTime()

Gets an estimate of the last time this object was used. If the class of the pooled object implements TrackedUse, what is returned is the maximum of TrackedUse.getLastUsedInstant() and getLastBorrowTime(); otherwise this method gives the same value as getLastBorrowTime().

Specified by:

getLastUsedTime in interface PooledObject<T>

Returns:

the last time this object was used

getObject

public T getObject()

Description copied from interface: PooledObject

Gets the underlying object that is wrapped by this instance of PooledObject.

Specified by:

getObject in interface PooledObject<T>

Returns:

The wrapped object.

getState

public PooledObjectState getState()

Gets the state of this object.

Specified by:

getState in interface PooledObject<T>

Returns:

state

invalidate

public void invalidate()

Sets the state to INVALID.

Specified by:

invalidate in interface PooledObject<T>

markAbandoned

public void markAbandoned()

Marks the pooled object as ABANDONED.

Specified by:

markAbandoned in interface PooledObject<T>

markReturning

public void markReturning()

Marks the pooled object as RETURNING.

Specified by:

markReturning in interface PooledObject<T>

printStackTrace

public void printStackTrace(PrintWriter writer)

Description copied from interface: PooledObject

Prints the stack trace of the code that borrowed this pooled object and the stack trace of the last code to use this object (if available) to the supplied writer.

Specified by:

printStackTrace in interface PooledObject<T>

Parameters:

writer - The destination for the debug output.

setLogAbandoned

public void setLogAbandoned(boolean logAbandoned)

Description copied from interface: PooledObject

Sets whether to use abandoned object tracking. If this is true the implementation will need to record the stack trace of the last caller to borrow this object.

Specified by:

setLogAbandoned in interface PooledObject<T>

Parameters:

logAbandoned - The new configuration setting for abandoned object tracking.

setRequireFullStackTrace

public void setRequireFullStackTrace(boolean requireFullStackTrace)

Configures the stack trace generation strategy based on whether or not fully detailed stack traces are required. When set to false, abandoned logs may only include caller class information rather than method names, line numbers, and other normal metadata available in a full stack trace.

Specified by:

setRequireFullStackTrace in interface PooledObject<T>

Parameters:

requireFullStackTrace - the new configuration setting for abandoned object logging

Since:

2.5

startEvictionTest

public boolean startEvictionTest()

Description copied from interface: PooledObject

Attempts to place the pooled object in the PooledObjectState.EVICTION state.

Specified by:

startEvictionTest in interface PooledObject<T>

Returns:

true if the object was placed in the PooledObjectState.EVICTION state otherwise false.

toString

public String toString()

Description copied from interface: PooledObject

Gets a String form of the wrapper for debug purposes. The format is not fixed and may change at any time.

Specified by:

toString in interface PooledObject<T>

Overrides:

toString in class Object

use

public void use()

Description copied from interface: PooledObject

Records the current stack trace as the last time the object was used.

Specified by:

use in interface PooledObject<T>