c3p0实现连接池

编译及运行环境：winxp+jdk5.0+eclipse3.2+oracle9i
所需jar包：
??? oracle9.jar（oralce驱动器）
??? c3p0-0.9.1.2.jar
??? log4j-1.2.8.jar
??? commons-logging.jar

SystemConfigResources.properties
#oracle config
DRIVER_NAME=oracle.jdbc.driver.OracleDriver
DATABASE_URL=jdbc:oracle:thin:@127.0.0.1:1521:WORK
DATABASE_USER=system
DATABASE_PASSWORD=manager
#c3p0 config
Initial_PoolSize=10
Min_PoolSize=10
Max_PoolSize=50
Acquire_Increment=10
TIMEOUT=5000
MAX_IdleTime=1800
Idle_Test_Period=3000
Validate=true

SystemConfig.java
package com.database.config;
import java.util.*;
public class SystemConfig {
??? static String configFile = "com.database.config.SystemConfigResources";
??? public static String getConfigInfomation(String itemIndex) {
??????? try {
??????????? ResourceBundle resource = ResourceBundle.getBundle(configFile);
??????????? return resource.getString(itemIndex);
??????? } catch (Exception e) {
??????????? return "";
??????? }
??? }
}

DatabaseAccessInterface.java
package com.database;
import java.sql.*;
import java.util.*;
public interface DatabaseAccessInterface {
??? public abstract void executeSQL(String sqlStatement) throws SQLException;
??? public abstract void executeSQL(String[] sqlStatement) throws SQLException;
??? public abstract void executeSQL(String sqlStatement, Object parameters[]) throws SQLException;
??? public abstract void executeSQL(String sqlStatement, List parameters) throws SQLException;
??? public abstract void executeSQL(String[] sqlStatement, List parameters) throws SQLException;
??? public abstract Vector executeQuerySQL(String sqlStatement) throws SQLException;
??? public abstract Vector executeQuerySQL(String sqlStatement, Object parameters[]) throws SQLException;
??? public abstract Vector executeQuerySQL(String sqlStatement, List parameters) throws SQLException;
??? public abstract String getSequenceNum(String tableName) throws SQLException;
}

DatabaseAccessFactory.java
package com.database;
public class DatabaseAccessFactory {
??? private static DatabaseAccessInterface databaseai = null;
??? public static DatabaseAccessInterface getDataAccessInstance() {
??????? if (databaseai == null) {
??????????? databaseai = new DatabaseAccessImpl();
??????? }
??????? return databaseai;
??? }
}

DBConnectionManager.java
package com.database;
import java.sql.*;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import com.database.config.*;
import com.mchange.v2.c3p0.*;
public class DBConnectionManager {
??? private static Log?????????????????? log = LogFactory.getLog(DatabaseAccessImpl.class);
??? private static ComboPooledDataSource cpds = null;
??? public static void init() {
??????? log.debug(">>>>>>>>>>>>>>>>>>>>> <DBConnectionManager.init> Begin");
??????? // 建立数据库连接池
??????? String DRIVER_NAME = SystemConfig.getConfigInfomation("DRIVER_NAME"); // 驱动器
??????? String DATABASE_URL = SystemConfig.getConfigInfomation("DATABASE_URL"); // 数据库连接url
??????? String DATABASE_USER = SystemConfig.getConfigInfomation("DATABASE_USER"); // 数据库用户名
??????? String DATABASE_PASSWORD = SystemConfig.getConfigInfomation("DATABASE_PASSWORD"); // 数据库密?码
??????? int Min_PoolSize = 5;
??????? int Max_PoolSize = 50;
??????? int Acquire_Increment = 5;
??????? int Initial_PoolSize = 10;
??????? int Idle_Test_Period = 3000;// 每隔3000s测试连接是否可以正常使用
??????? String Validate = SystemConfig.getConfigInfomation("Validate");// 每次连接验证连接是否可用
??????? if (Validate.equals("")) {??????????? Validate = "false";??????? }
??????? // 最小连接数
??????? try {
??????????? Min_PoolSize = Integer.parseInt(SystemConfig.getConfigInfomation("Min_PoolSize"));
??????? } catch (Exception ex) {
??????????? ex.printStackTrace();
??????? }
??????? // 增量条数
??????? try {
??????????? Acquire_Increment = Integer.parseInt(SystemConfig.getConfigInfomation("Acquire_Increment"));
??????? } catch (Exception ex) {
??????????? ex.printStackTrace();
??????? }
??????? // 最大连接数
??????? try {
??????????? Max_PoolSize = Integer.parseInt(SystemConfig.getConfigInfomation("Max_PoolSize"));
??????? } catch (Exception ex) {
??????????? ex.printStackTrace();
??????? }
??????? // 初始化连接数
??????? try {
??????????? Initial_PoolSize = Integer.parseInt(SystemConfig.getConfigInfomation("Initial_PoolSize"));
??????? } catch (Exception ex) {
??????????? ex.printStackTrace();
??????? }
??????? // 每隔3000s测试连接是否可以正常使用
??????? try {
??????????? Idle_Test_Period = Integer.parseInt(SystemConfig.getConfigInfomation("Idle_Test_Period"));
??????? } catch (Exception ex) {
??????????? ex.printStackTrace();
??????? }

??????? try {
??????????? cpds = new ComboPooledDataSource();
??????????? cpds.setDriverClass(DRIVER_NAME); // 驱动器
??????????? cpds.setJdbcUrl(DATABASE_URL); // 数据库url
??????????? cpds.setUser(DATABASE_USER); // 用户名
??????????? cpds.setPassword(DATABASE_PASSWORD); // 密码
??????????? cpds.setInitialPoolSize(Initial_PoolSize); // 初始化连接池大小
??????????? cpds.setMinPoolSize(Min_PoolSize); // 最少连接数
??????????? cpds.setMaxPoolSize(Max_PoolSize); // 最大连接数
??????????? cpds.setAcquireIncrement(Acquire_Increment); // 连接数的增量
??????????? cpds.setIdleConnectionTestPeriod(Idle_Test_Period); // ?测连接有效的时间间隔
??????????? cpds.setTestConnectionOnCheckout(Boolean.getBoolean(Validate)); // 每次连接验证连接是否可用
??????? } catch (Exception ex) {
??????????? ex.printStackTrace();
??????? }
??????? log.debug(">>>>>>>>>>>>>>>>>>>>> <DBConnectionManager.init> End");
??? }

??? public static Connection getConnection() {// 获取数据库连接
??????? Connection connection = null;
??????? try {
??????????? if (cpds == null) {
??????????????? init();
??????????? }
??????????? connection = cpds.getConnection(); // getconnection
??????? } catch (SQLException ex) {
??????????? ex.printStackTrace();
??????? }
??????? return connection;
??? }

??? public static void release() {
??????? try {
??????????? if (cpds != null) {
??????????????? cpds.close();
??????????? }
??????? } catch (Exception ex) {
??????????? ex.printStackTrace();
??????? }
??? }
}