Package org.springframework.integration.util

Class SimplePool<T>

java.lang.Object
org.springframework.integration.util.SimplePool<T>
Type Parameters:
T - pool element type.
All Implemented Interfaces:
Pool<T>
public class SimplePool<T> extends Object implements Pool<T>
Implementation of Pool supporting dynamic resizing and a variable timeout when attempting to obtain an item from the pool. Pool grows on demand up to the limit.
Since:
2.2
Author:
Gary Russell, Sergey Bogatyrev, Artem Bilan, Christian Tzolov

  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Class
    Description
    static interface 
    SimplePool.PoolItemCallback<T>
    User of the pool provide an implementation of this interface; called during various pool operations.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    protected final Log
    logger
     

  • Constructor Summary

    Constructors
    Constructor
    Description
    SimplePool(int poolSize, SimplePool.PoolItemCallback<T> callback)
    Create a SimplePool with a specific limit.

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    close()
    Close the pool; returned items will be destroyed.
    int
    getActiveCount()
    Return the number of allocated items that are currently checked out of the pool.
    int
    getAllocatedCount()
    Return the current count of allocated items (in use and idle).
    int
    getIdleCount()
    Return the number of items that have been allocated but are not currently in use.
    T
    getItem()
    Obtain an item from the pool; waits up to waitTime milliseconds (default infinity).
    int
    getPoolSize()
    Return the current size of the pool; may be greater than the target pool size if it was recently reduced and too many items were in use to allow the new size to be set.
    void
    releaseItem(T item)
    Return an item to the pool.
    void
    removeAllIdleItems()
    Remove all idle items from the pool.
    void
    setPoolSize(int poolSize)
    Adjust the current pool size.
    void
    setWaitTimeout(long waitTimeout)
    Adjust the wait timeout - the time for which getItem() will wait if no idle entries are available.

    Methods inherited from class java.lang.Object

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

  • Field Details

    • logger

      protected final Log logger

  • Constructor Details

    • SimplePool

      public SimplePool(int poolSize, SimplePool.PoolItemCallback<T> callback)
      Create a SimplePool with a specific limit.
      Parameters:
      poolSize - The maximum number of items the pool supports.
      callback - A SimplePool.PoolItemCallback implementation called during various pool operations.

  • Method Details

    • setPoolSize

      public void setPoolSize(int poolSize)
      Adjust the current pool size. When reducing the pool size, attempts to remove the delta from the pool. If there are not enough unused items in the pool, the actual pool size will decrease to the specified size as in-use items are returned.
      Parameters:
      poolSize - The desired target pool size.

    • getPoolSize

      public int getPoolSize()
      Return the current size of the pool; may be greater than the target pool size if it was recently reduced and too many items were in use to allow the new size to be set.
      Specified by:
      getPoolSize in interface Pool<T>
      Returns:
      the size.

    • getIdleCount

      public int getIdleCount()
      Description copied from interface: Pool
      Return the number of items that have been allocated but are not currently in use.
      Specified by:
      getIdleCount in interface Pool<T>
      Returns:
      The number of items.

    • getActiveCount

      public int getActiveCount()
      Description copied from interface: Pool
      Return the number of allocated items that are currently checked out of the pool.
      Specified by:
      getActiveCount in interface Pool<T>
      Returns:
      The number of items.

    • getAllocatedCount

      public int getAllocatedCount()
      Description copied from interface: Pool
      Return the current count of allocated items (in use and idle). May be less than the pool size, and reflects the high watermark of pool usage.
      Specified by:
      getAllocatedCount in interface Pool<T>
      Returns:
      the number of items.

    • setWaitTimeout

      public void setWaitTimeout(long waitTimeout)
      Adjust the wait timeout - the time for which getItem() will wait if no idle entries are available.
      Default: infinity.
      Parameters:
      waitTimeout - The wait timeout in milliseconds.

    • getItem

      public T getItem()
      Obtain an item from the pool; waits up to waitTime milliseconds (default infinity).
      Specified by:
      getItem in interface Pool<T>
      Returns:
      the item.
      Throws:
      PoolItemNotAvailableException - if no items become available in time.

    • releaseItem

      public void releaseItem(T item)
      Return an item to the pool.
      Specified by:
      releaseItem in interface Pool<T>
      Parameters:
      item - the item.

    • removeAllIdleItems

      public void removeAllIdleItems()
      Description copied from interface: Pool
      Remove all idle items from the pool.
      Specified by:
      removeAllIdleItems in interface Pool<T>

    • close

      public void close()
      Description copied from interface: Pool
      Close the pool; returned items will be destroyed.
      Specified by:
      close in interface Pool<T>