Package org.apache.commons.pool2.impl

# Class DefaultPooledObject<T>

java.lang.Object
org.apache.commons.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.commons.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>`