Package org.apache.commons.pool

Class PoolUtils.ObjectPoolAdaptor<V>

  • All Implemented Interfaces:
    ObjectPool<V>
    Enclosing class:
    PoolUtils
    private static class PoolUtils.ObjectPoolAdaptor<V>
extends java.lang.Object
implements ObjectPool<V>
    Adapts a KeyedObjectPool to make it an ObjectPool by fixing restricting to a fixed key.

    • Field Summary

      Fields 
      Modifier and Type Field Description
      private java.lang.Object key
      Fixed key
      private KeyedObjectPool<java.lang.Object,​V> keyedPool
      Underlying KeyedObjectPool

    • Constructor Summary

      Constructors 
      Constructor Description
      ObjectPoolAdaptor​(KeyedObjectPool<java.lang.Object,​V> keyedPool, java.lang.Object key)
      Create a new ObjectPoolAdaptor using the provided KeyedObjectPool and fixed key.

    • Method Summary

      All Methods Instance Methods Concrete Methods Deprecated Methods 
      Modifier and Type Method Description
      void addObject()
      Create an object using the factory or other implementation dependent mechanism, passivate it, and then place it in the idle object pool.
      V borrowObject()
      Obtains an instance from this 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 getNumActive()
      Return the number of instances currently borrowed from this pool (optional operation).
      int getNumIdle()
      Return the number of instances currently idle in this pool (optional operation).
      void invalidateObject​(V obj)
      Invalidates an object from the pool.
      void returnObject​(V obj)
      Return an instance to the pool.
      void setFactory​(PoolableObjectFactory<V> factory)
      Deprecated.
      to be removed in version 2.0
      java.lang.String toString()

      • Methods inherited from class java.lang.Object

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

    • Field Detail

      • key

        private final java.lang.Object key
        Fixed key

      • keyedPool

        private final KeyedObjectPool<java.lang.Object,​V> keyedPool
        Underlying KeyedObjectPool

    • Constructor Detail

      • ObjectPoolAdaptor

        ObjectPoolAdaptor​(KeyedObjectPool<java.lang.Object,​V> keyedPool,
                  java.lang.Object key)
           throws java.lang.IllegalArgumentException
        Create a new ObjectPoolAdaptor using the provided KeyedObjectPool and fixed key.
        Parameters:
        keyedPool - underlying KeyedObjectPool
        key - fixed key
        Throws:
        java.lang.IllegalArgumentException - if either of the parameters is null

    • Method Detail

      • borrowObject

        public V borrowObject()
               throws java.lang.Exception,
                      java.util.NoSuchElementException,
                      java.lang.IllegalStateException
        Obtains an instance from this pool.

        Instances returned from this method will have been either newly created with makeObject or will be a previously idle object and have been activated with activateObject and then validated with validateObject.

        By contract, clients must return the borrowed instance using returnObject, invalidateObject, 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 strictly specified (although it may be specified by implementations). Older versions of this method would return null to indicate exhaustion, newer versions are encouraged to throw a NoSuchElementException.

        Specified by:
        borrowObject in interface ObjectPool<V>
        Returns:
        an instance from this pool.
        Throws:
        java.lang.IllegalStateException - after close has been called on this pool.
        java.lang.Exception - when makeObject throws an exception.
        java.util.NoSuchElementException - when the pool is exhausted and cannot or will not return another instance.

      • returnObject

        public void returnObject​(V obj)
        Return an instance to the 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<V>
        Parameters:
        obj - a borrowed instance to be returned.

      • invalidateObject

        public void invalidateObject​(V obj)

        Invalidates an object from the pool.

        By contract, obj must have been obtained using borrowObject or a related method as defined in an implementation or sub-interface.

        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<V>
        Parameters:
        obj - a borrowed instance to be disposed.

      • addObject

        public void addObject()
               throws java.lang.Exception,
                      java.lang.IllegalStateException
        Create an object using the factory or other implementation dependent mechanism, passivate it, and then place it in the idle object pool. addObject is useful for "pre-loading" a pool with idle objects. (Optional operation).
        Specified by:
        addObject in interface ObjectPool<V>
        Throws:
        java.lang.Exception - when PoolableObjectFactory.makeObject() fails.
        java.lang.IllegalStateException - after ObjectPool.close() has been called on this pool.
        java.lang.UnsupportedOperationException - when this pool cannot add new idle objects.

      • getNumIdle

        public int getNumIdle()
               throws java.lang.UnsupportedOperationException
        Return the number of instances currently idle in this pool (optional operation). This may be considered an approximation of the number of objects that can be borrowed without creating any new instances. Returns a negative value if this information is not available.
        Specified by:
        getNumIdle in interface ObjectPool<V>
        Returns:
        the number of instances currently idle in this pool or a negative value if unsupported
        Throws:
        java.lang.UnsupportedOperationException - deprecated: if this implementation does not support the operation

      • getNumActive

        public int getNumActive()
                 throws java.lang.UnsupportedOperationException
        Return the number of instances currently borrowed from this pool (optional operation). Returns a negative value if this information is not available.
        Specified by:
        getNumActive in interface ObjectPool<V>
        Returns:
        the number of instances currently borrowed from this pool or a negative value if unsupported
        Throws:
        java.lang.UnsupportedOperationException - deprecated: if this implementation does not support the operation

      • clear

        public void clear()
           throws java.lang.Exception,
                  java.lang.UnsupportedOperationException
        Clears any objects sitting idle in the pool, releasing any associated resources (optional operation). Idle objects cleared must be destroyed.
        Specified by:
        clear in interface ObjectPool<V>
        Throws:
        java.lang.UnsupportedOperationException - if this implementation does not support the operation
        java.lang.Exception

      • setFactory

        @Deprecated
public void setFactory​(PoolableObjectFactory<V> factory)
                throws java.lang.IllegalStateException,
                       java.lang.UnsupportedOperationException
        Deprecated.
        to be removed in version 2.0
        Sets the PoolableObjectFactory for the pool.
        Specified by:
        setFactory in interface ObjectPool<V>
        Parameters:
        factory - new PoolableObjectFactory
        Throws:
        java.lang.IllegalStateException - when the factory cannot be set at this time
        java.lang.UnsupportedOperationException - if this implementation does not support the operation

      • toString

        public java.lang.String toString()
        Overrides:
        toString in class java.lang.Object