Java tutorial
/* * Copyright 2004-2005 OpenSymphony * * Licensed under the Apache License, Version 2.0 (the "License"); you may not * use this file except in compliance with the License. You may obtain a copy * of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the * License for the specific language governing permissions and limitations * under the License. * */ /* * Previously Copyright (c) 2001-2004 James House */ package com.icbc.Scheduler.DA; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.Properties; import com.icbc.Scheduler.Core.SchedulerEnviornment; import com.icbc.Scheduler.Global.GlobalDefine; import com.icbc.Scheduler.Log.LogProvider; import com.icbc.Scheduler.Util.*; import org.apache.commons.dbcp.BasicDataSource; /** * <p> * A <code>ConnectionProvider</code> implementation that creates it's own * pool of connections. * </p> * * <p> * This class uses <a href="http://jakarta.apache.org/commons/index.html">DBCP * </a>, an Apache-Jakarta-Commons product. * </p> * * @see DBConnectionManager * @see ConnectionProvider * * @author Sharada Jambula * @author James House * @author Mohammad Rezaei */ public class PoolingConnectionProvider implements ConnectionProvider { /* * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * * Constants. * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ // The JDBC database driver public static final String DB_DRIVER = "driver"; // The JDBC database URL public static final String DB_URL = "URL"; // The database user name public static final String DB_USER = "user"; // The database user password public static final String DB_PASSWORD = "password"; public static final String DB_MAX_CONNECTIONS = "maxConnections"; public static final String DB_VALIDATION_QUERY = "validationQuery"; //Count of connection public static int m_iUsingConnectionCount = 0; /* * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * * Data members. * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ private BasicDataSource datasource; //the status of Connection;when connection is abnormal,status will be -1 private int m_iConnectionStatus = 0; /* * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * * Constructors. * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ public PoolingConnectionProvider(String dbDriver, String dbURL, String dbUser, String dbPassword, int maxConnections, String dbValidationQuery) throws SQLException { initialize(dbDriver, dbURL, dbUser, dbPassword, maxConnections, dbValidationQuery); } /* * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * * Interface. * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ private void initialize(String dbDriver, String dbURL, String dbUser, String dbPassword, int maxConnections, String dbValidationQuery) throws SQLException { if (dbDriver == null) { throw new SQLException("DB driver class name cannot be null!"); } if (dbURL == null) { throw new SQLException("DB URL cannot be null!"); } if (maxConnections < 0) { throw new SQLException("Max connections must be greater than zero!"); } datasource = new BasicDataSource(); datasource.setDriverClassName(dbDriver); datasource.setUrl(dbURL); datasource.setUsername(dbUser); datasource.setPassword(dbPassword); datasource.setMaxActive(maxConnections); datasource.setTestOnBorrow(true); //datasource.setLoginTimeout(5); // datasource.setLoginTimeout(-1); // datasource.setMaxWait(-1); if (dbValidationQuery != null) { datasource.setValidationQuery(dbValidationQuery); } else { datasource.setValidationQuery("select SYSDATE FROM DUAL"); } } /** * <p> * Create a connection pool using the given properties. * </p> * * <p> * The properties passed should contain: * * <UL> * <LI>{@link #DB_DRIVER}- The database driver class name * <LI>{@link #DB_URL}- The database URL * <LI>{@link #DB_USER}- The database user * <LI>{@link #DB_PASSWORD}- The database password * <LI>{@link #DB_MAX_CONNECTIONS}- The maximum # connections in the pool * </UL> * <P> * * @param config * configuration properties * @exception SQLException * if an error occurs */ public PoolingConnectionProvider(Properties config) throws Exception { PropertiesParser cfg = new PropertiesParser(config); String url = cfg.getStringProperty(DB_URL); try { initialize(cfg.getStringProperty(DB_DRIVER), url, cfg.getStringProperty(DB_USER), cfg.getStringProperty(DB_PASSWORD), cfg.getIntProperty(DB_MAX_CONNECTIONS), cfg.getStringProperty(DB_VALIDATION_QUERY)); } catch (Exception e) { LogProvider.outException(e, "", PoolingConnectionProvider.class.getName()); throw e; } } /** * <p>Get a connection from DBCP</p> * @exception SQLException * if any error occurs * */ public Connection getConnection() throws SQLException { return this.datasource.getConnection(); } /** * <p>Shutdown DBCP</p> * @exception SQLException * if any error occurs * */ public void shutdown() throws SQLException { this.datasource.close(); } /** * <p>Short ping PoolingConnectionProvider</p> * @return int: * 1: Ping successfully. * 0: Ping unsuccessfully. */ public int pings() { int t_iPingResult = GlobalDefine.PING_SUCCESS; String t_sSql = ""; Connection t_Conn = null; ResultSet t_rsResult = null; PreparedStatement t_PStat = null; try { /*Get connection*/ t_Conn = getConnection(); /*Get ping SQL*/ t_sSql = DBConstantsProvider.getInstance().getPingsSQL(); /*Execute ping SQL*/ t_PStat = t_Conn.prepareStatement(t_sSql); t_rsResult = t_PStat.executeQuery(); /*Execute successfully*/ t_iPingResult = GlobalDefine.PING_SUCCESS; if (m_iConnectionStatus == -1) { LogProvider.outLog("INFO", "Error Connection turns normal", GlobalDefine.LOG_LOGGER_DB, SchedulerEnviornment.class.getName()); } m_iConnectionStatus = 0; } catch (Exception e) { t_iPingResult = GlobalDefine.PING_ERROR_GENERAL; if (m_iConnectionStatus == 0) { LogProvider.outException(e, "t_sSql:" + t_sSql, SchedulerEnviornment.class.getName()); } m_iConnectionStatus = -1; return t_iPingResult; } finally { if (t_rsResult != null) { try { t_rsResult.close(); } catch (Exception e) { LogProvider.outException(e, "t_rsResult.close() error in pings", StdSchedulerDA.class.getName()); } } if (t_Conn != null) { try { t_Conn.close(); } catch (Exception e) { LogProvider.outException(e, "Conn.close() error in pings", StdSchedulerDA.class.getName()); } } } return t_iPingResult; } /** * <p>Long ping PoolingConnectionProvider</p> * @return String: Ping msg */ public String pingl() { String t_sPingResult = ""; String t_sSql = ""; String t_sFormatStr = ""; IFConfigFileParser t_INIFile = null; Connection t_Conn = null; ResultSet t_rsResult = null; PreparedStatement t_PStat = null; try { /*Get connection*/ t_Conn = getConnection(); /*Get ping SQL*/ t_sSql = DBConstantsProvider.getInstance().getPinglSQL(); /*Execute ping SQL*/ t_PStat = t_Conn.prepareStatement(t_sSql); t_rsResult = t_PStat.executeQuery(); /*Get ping result*/ t_INIFile = ConfigFileManager.getInstance().getConfigFilePaser(GlobalDefine.INIMAIN); t_sFormatStr = t_INIFile.getStringProperty("PING_FORMAT_DB"); t_sPingResult = t_sFormatStr; t_INIFile = ConfigFileManager.getInstance().getConfigFilePaser(GlobalDefine.INICTLTABLE); while (t_rsResult.next()) { t_sPingResult = t_sPingResult.replaceAll(GlobalDefine.PING_FORMAT_DB_MSG, t_rsResult.getString(t_INIFile.getStringProperty("T_PING_PING_MSG").trim())); } } catch (Exception e) { LogProvider.outException(e, "", "ping"); t_sPingResult = GlobalDefine.PING_ERROR; return t_sPingResult; } finally { if (t_rsResult != null) { try { t_rsResult.close(); } catch (Exception e) { } } if (t_Conn != null) { try { t_Conn.close(); } catch (Exception e) { } } } return t_sPingResult; } }