001 /* 002 * Copyright 2001,2004 The Apache Software Foundation. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * http://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017 package org.apache.commons.scaffold.sql; 018 019 020 import java.sql.SQLException; 021 022 import javax.servlet.http.HttpServlet; 023 import javax.sql.DataSource; 024 025 026 /** 027 * Connection adaptor for a connection pool that is exposed 028 * through the servlet context, like the Struts generic 029 * connection pool. 030 * <p> 031 * The ConnectionServlet will automatically set a reference 032 * to itself if an instance of this class is specified 033 * as the ConnectionAdaptor. 034 * 035 * @author Ted Husted 036 * @version $Revision: 155464 $ $Date: 2005-02-26 13:26:54 +0000 (Sat, 26 Feb 2005) $ 037 */ 038 public class ServletAdaptor extends ConnectionAdaptor { 039 040 041 /** 042 * Field to store a link to a servlet in the application. 043 */ 044 private static HttpServlet servlet = null; 045 046 047 /** 048 * Set a reference to a servlet in the application 049 * to allow access to the servlet context. 050 */ 051 public void setServlet(HttpServlet servlet) { 052 ServletAdaptor.servlet = servlet; 053 } 054 055 056 /** 057 * Return datasource from the servlet context using 058 * key as the attribute name. 059 * 060 * @param key The attribute name for the resource. 061 * If null is passed, null is returned. 062 * @returns null or the datasource object related to "key" 063 */ 064 protected DataSource getDataSource(String key) 065 throws SQLException { 066 067 if (null==key) return null; 068 069 return (DataSource) 070 servlet.getServletContext().getAttribute(key); 071 072 } 073 074 075 // Required 076 public ServletAdaptor() { 077 078 if (null==pool) pool = this; 079 080 } 081 082 } // end ServletAdaptor 083