Class BaseObjectPool<T>

  • Type Parameters:
    T - the type of objects held in this pool
    All Implemented Interfaces:
    ObjectPool<T>
    Direct Known Subclasses:
    GenericObjectPool, SoftReferenceObjectPool, StackObjectPool

    public abstract class BaseObjectPool<T>
    extends java.lang.Object
    implements ObjectPool<T>
    A simple base implementation of ObjectPool. Optional operations are implemented to either do nothing, return a value indicating it is unsupported or throw UnsupportedOperationException.
    Since:
    Pool 1.0
    Version:
    $Revision: 1222396 $ $Date: 2011-12-22 14:02:25 -0500 (Thu, 22 Dec 2011) $
    • Field Summary

      Fields 
      Modifier and Type Field Description
      private boolean closed
      Whether or not the pool is closed
    • Constructor Summary

      Constructors 
      Constructor Description
      BaseObjectPool()  
    • Field Detail

      • closed

        private volatile boolean closed
        Whether or not the pool is closed
    • Constructor Detail

      • BaseObjectPool

        public BaseObjectPool()
    • Method Detail

      • borrowObject

        public abstract T borrowObject()
                                throws java.lang.Exception
        Obtains an instance from the pool.
        Specified by:
        borrowObject in interface ObjectPool<T>
        Returns:
        an instance from the pool
        Throws:
        java.lang.Exception - if an instance cannot be obtained from the pool
      • returnObject

        public abstract void returnObject​(T obj)
                                   throws java.lang.Exception
        Returns an instance to the pool.
        Specified by:
        returnObject in interface ObjectPool<T>
        Parameters:
        obj - instance to return to the pool
        Throws:
        java.lang.Exception
      • invalidateObject

        public abstract void invalidateObject​(T obj)
                                       throws java.lang.Exception

        Invalidates an object from the pool.

        By contract, obj must have been obtained using borrowObject.

        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<T>
        Parameters:
        obj - a borrowed instance to be disposed.
        Throws:
        java.lang.Exception
      • getNumIdle

        public int getNumIdle()
                       throws java.lang.UnsupportedOperationException
        Not supported in this base implementation.
        Specified by:
        getNumIdle in interface ObjectPool<T>
        Returns:
        a negative value.
        Throws:
        java.lang.UnsupportedOperationException
      • getNumActive

        public int getNumActive()
                         throws java.lang.UnsupportedOperationException
        Not supported in this base implementation.
        Specified by:
        getNumActive in interface ObjectPool<T>
        Returns:
        a negative value.
        Throws:
        java.lang.UnsupportedOperationException
      • clear

        public void clear()
                   throws java.lang.Exception,
                          java.lang.UnsupportedOperationException
        Not supported in this base implementation.
        Specified by:
        clear in interface ObjectPool<T>
        Throws:
        java.lang.UnsupportedOperationException
        java.lang.Exception
      • addObject

        public void addObject()
                       throws java.lang.Exception,
                              java.lang.UnsupportedOperationException
        Not supported in this base implementation. Always throws an UnsupportedOperationException, subclasses should override this behavior.
        Specified by:
        addObject in interface ObjectPool<T>
        Throws:
        java.lang.UnsupportedOperationException
        java.lang.Exception - when PoolableObjectFactory.makeObject() fails.
        java.lang.IllegalStateException - after ObjectPool.close() has been called on this pool.
      • close

        public void close()
                   throws java.lang.Exception
        Close this pool. This affects the behavior of isClosed and assertOpen.
        Specified by:
        close in interface ObjectPool<T>
        Throws:
        java.lang.Exception - deprecated: implementations should silently fail if not all resources can be freed.
      • setFactory

        @Deprecated
        public void setFactory​(PoolableObjectFactory<T> factory)
                        throws java.lang.IllegalStateException,
                               java.lang.UnsupportedOperationException
        Deprecated.
        to be removed in pool 2.0
        Not supported in this base implementation. Always throws an UnsupportedOperationException, subclasses should override this behavior.
        Specified by:
        setFactory in interface ObjectPool<T>
        Parameters:
        factory - the PoolableObjectFactory
        Throws:
        java.lang.UnsupportedOperationException
        java.lang.IllegalStateException
      • isClosed

        public final boolean isClosed()
        Has this pool instance been closed.
        Returns:
        true when this pool has been closed.
      • assertOpen

        protected final void assertOpen()
                                 throws java.lang.IllegalStateException
        Throws an IllegalStateException when this pool has been closed.
        Throws:
        java.lang.IllegalStateException - when this pool has been closed.
        See Also:
        isClosed()