新手写的一个DBCP工具类

package com.xx.questionnaire.util.dao;

import java.io.IOException;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;

import javax.sql.DataSource;

import org.apache.commons.dbcp2.BasicDataSourceFactory;
import org.apache.log4j.Logger;

/**
* @version 0.1
* @author Administrator
*
*/
public class Dbcp_connection implements JdbcI {
static Logger log = Logger.getLogger(Dbcp_connection.class);
private Connection connection;
/**
* 在静态块中初始化获得DBCP数据源连接池
*/
static {
getDataSource();
log.info("数据源已在静态块中初始化完成。");
}

/**
*@return 返回Connection连接
*/
public Connection getConnection() {
if (connection == null || connection.equals("")) {
try {
setConnection(getDataSource().getConnection());
log.info("从数据源中获取连接！");
return connection;
} catch (SQLException e) {
log.error("对不起，数据库连接获取失败！");
e.printStackTrace();
}
}
return null;
}
/**
* @param sql    SQL语句
* @return PrepaedStatement对象
*/
public PreparedStatement getPStatement(String sql) {
if (sql == null || sql.equals("")) {
log.error("错误，SQL语句不允许为空!");
return null;
}
PreparedStatement ps = null;
try {
ps = getConnection().prepareStatement(sql);
log.info("SQL语句" + sql + "已经过预编译！");
return ps;
} catch (SQLException e) {
log.error("异常，SQL语句" + sql + "预编译失败！");
e.printStackTrace();
}

return null;
}

/**
* 强制释放Connection连接。
*
*/
public void close() {
try {
this.connection.close();
log.info("Connection object" + this.connection.hashCode()
+ "被强制释放！");
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

}

public void close(Statement ps) {
// TODO Auto-generated method stub
try {

ps.close();
this.connection.close();
log.info("Statement（"
+ ps.hashCode() + "），Connection("
+ this.connection.hashCode() + ")已被释放！");
} catch (SQLException e) {
log.error("异常，JDBC对象关闭失败！");
e.printStackTrace();
}

}
/**
* 按照顺序释放JDBC连接。
*/
public void close(Statement ps, ResultSet rs) {
// TODO Auto-generated method stub
try {
rs.close();
ps.close();
this.connection.close();
log.info("ResultSet（" + rs.hashCode() + "），Statement（"
+ ps.hashCode() + "），Connection("
+ this.connection.hashCode() + ")已被释放！");
} catch (SQLException e) {
log.error("异常，JDBC对象关闭失败！");
e.printStackTrace();
}

}

public static void main(String[] args) {
// TODO Auto-generated method stub
/* 1 */
DataSource dds = getDataSource();
System.out.println(dds == null ? "数据源失败" : "数据源成功");

}

/**
* 全局公用的数据源
*
* @return DataSource Object
*/
private static DataSource getDataSource() {
String dbcpUrl = "dbcp-mysql.properties";

DataSource ds;
Properties p = new Properties();
try {
// 通过类的类加载器将属性文件加载至输入流
p.load(JDBCUtil.class.getClassLoader().getResourceAsStream(dbcpUrl));
log.info("DBCP配置文件已加载！");

ds = BasicDataSourceFactory.createDataSource(p);
log.info("数据源获取成功！");
return ds;

} catch (IOException e) {
log.error("异常，可能是配置文件读取失败。");
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}

return null;
}

private void setConnection(Connection connection) {
log.info("获取连接，Hash地址为：" + connection.hashCode());
this.connection = connection;
}

public DataSource getDS() {
// TODO Auto-generated method stub
log.info("数据源被外部调用！");
return getDataSource();
}

}