Package org.apache.xalan.lib.sql

Class JNDIConnectionPool

  • All Implemented Interfaces:
    ConnectionPool
    public class JNDIConnectionPool
extends java.lang.Object
implements ConnectionPool
    A Connection Pool that wraps a JDBC datasource to provide connections. An instance of this class is created by XConnection when it attempts to resolves a ConnectionPool name as a JNDI data source. Most methods in this implementation do nothing since configuration is handled by the underlying JDBC datasource. Users should always call XConnection.close() from their stylsheet to explicitely close their connection. However, since there is no way to enforce this (Yikes!), it is recommended that a relatively short datasource timeout be used to prevent dangling connections.

    • Constructor Summary

      Constructors 
      Constructor Description
      JNDIConnectionPool()
      Use of the default constructor requires the jndi path to be set via setJndiPath().
      JNDIConnectionPool​(java.lang.String jndiDatasourcePath)
      Creates a connection pool with a specified JNDI path.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void freeUnused()
      Intended to release unused connections from the pool.
      java.sql.Connection getConnection()
      Returns a connection from the JDNI DataSource found at the JNDI Datasource path.
      java.lang.String getJndiPath()
      Returns the path for the jndi datasource
      boolean hasActiveConnections()
      Always returns false, indicating that this wrapper has no idea of what connections the underlying JNDI source is maintaining.
      boolean isEnabled()
      Always returns true.
      void releaseConnection​(java.sql.Connection con)
      Return a connection to the pool, the connection may be closed if the pool is inactive or has exceeded the max number of free connections
      void releaseConnectionOnError​(java.sql.Connection con)
      Provide a mechinism to return a connection to the pool on Error.
      void setDriver​(java.lang.String d)
      Not implemented and will throw an Error if called.
      void setJndiPath​(java.lang.String jndiPath)
      Sets the path for the jndi datasource
      void setMinConnections​(int n)
      Ignored in this implementation b/c the pooling is determined by the jndi dataosource.
      void setPassword​(java.lang.String p)
      Sets the password for the connection.
      void setPoolEnabled​(boolean flag)
      Releases the reference to the jndi datasource.
      void setProtocol​(java.util.Properties p)
      Ignored in this implementation b/c the pooling is determined by the jndi dataosource.
      void setURL​(java.lang.String url)
      Not implemented and will throw an Error if called.
      void setUser​(java.lang.String u)
      Sets the user name for the connection.
      boolean testConnection()
      A simple test to see if the jndi datasource exists.

      • Methods inherited from class java.lang.Object

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

    • Constructor Detail

      • JNDIConnectionPool

        public JNDIConnectionPool()
        Use of the default constructor requires the jndi path to be set via setJndiPath().

      • JNDIConnectionPool

        public JNDIConnectionPool​(java.lang.String jndiDatasourcePath)
        Creates a connection pool with a specified JNDI path.
        Parameters:
        jndiDatasourcePath - Complete path to the JNDI datasource

    • Method Detail

      • setJndiPath

        public void setJndiPath​(java.lang.String jndiPath)
        Sets the path for the jndi datasource
        Parameters:
        jndiPath -

      • getJndiPath

        public java.lang.String getJndiPath()
        Returns the path for the jndi datasource
        Parameters:
        jndiPath -

      • isEnabled

        public boolean isEnabled()
        Always returns true. This method was intended to indicate if the pool was enabled, however, in this implementation that is not relavant.
        Specified by:
        isEnabled in interface ConnectionPool
        Returns:

      • setDriver

        public void setDriver​(java.lang.String d)
        Not implemented and will throw an Error if called. Connection configuration is handled by the underlying JNDI DataSource.
        Specified by:
        setDriver in interface ConnectionPool
        Parameters:
        d -

      • setURL

        public void setURL​(java.lang.String url)
        Not implemented and will throw an Error if called. Connection configuration is handled by the underlying JNDI DataSource.
        Specified by:
        setURL in interface ConnectionPool
        Parameters:
        d -

      • freeUnused

        public void freeUnused()
        Intended to release unused connections from the pool. Does nothing in this implementation.
        Specified by:
        freeUnused in interface ConnectionPool

      • hasActiveConnections

        public boolean hasActiveConnections()
        Always returns false, indicating that this wrapper has no idea of what connections the underlying JNDI source is maintaining.
        Specified by:
        hasActiveConnections in interface ConnectionPool
        Returns:

      • setPassword

        public void setPassword​(java.lang.String p)
        Sets the password for the connection. If the jndi datasource does not require a password (which is typical), this can be left null.
        Specified by:
        setPassword in interface ConnectionPool
        Parameters:
        p - the password

      • setUser

        public void setUser​(java.lang.String u)
        Sets the user name for the connection. If the jndi datasource does not require a user name (which is typical), this can be left null.
        Specified by:
        setUser in interface ConnectionPool
        Parameters:
        u - the user name

      • getConnection

        public java.sql.Connection getConnection()
                                  throws java.sql.SQLException
        Returns a connection from the JDNI DataSource found at the JNDI Datasource path.
        Specified by:
        getConnection in interface ConnectionPool
        Returns:
        Throws:
        java.sql.SQLException

      • releaseConnection

        public void releaseConnection​(java.sql.Connection con)
                       throws java.sql.SQLException
        Description copied from interface: ConnectionPool
        Return a connection to the pool, the connection may be closed if the pool is inactive or has exceeded the max number of free connections
        Specified by:
        releaseConnection in interface ConnectionPool
        Throws:
        java.sql.SQLException

      • releaseConnectionOnError

        public void releaseConnectionOnError​(java.sql.Connection con)
                              throws java.sql.SQLException
        Description copied from interface: ConnectionPool
        Provide a mechinism to return a connection to the pool on Error. A good default behaviour is to close this connection and build a new one to replace it. Some JDBC impl's won't allow you to reuse a connection after an error occurs.
        Specified by:
        releaseConnectionOnError in interface ConnectionPool
        Throws:
        java.sql.SQLException

      • setPoolEnabled

        public void setPoolEnabled​(boolean flag)
        Releases the reference to the jndi datasource. The original intention of this method was to actually turn the pool *off*. Since we are not managing the pool, we simply release our reference to the datasource. Future calls to the getConnection will simply recreate the datasource.
        Specified by:
        setPoolEnabled in interface ConnectionPool
        Parameters:
        flag - If false, the reference to the datasource is released.

      • setProtocol

        public void setProtocol​(java.util.Properties p)
        Ignored in this implementation b/c the pooling is determined by the jndi dataosource.
        Specified by:
        setProtocol in interface ConnectionPool
        Parameters:
        p -

      • setMinConnections

        public void setMinConnections​(int n)
        Ignored in this implementation b/c the pooling is determined by the jndi dataosource.
        Specified by:
        setMinConnections in interface ConnectionPool
        Parameters:
        n -

      • testConnection

        public boolean testConnection()
        A simple test to see if the jndi datasource exists. Note that this test does not ensure that the datasource will return valid connections.
        Specified by:
        testConnection in interface ConnectionPool