新手写的一个DBCP工具类

  1 package com.xx.questionnaire.util.dao;
  2 
  3 import java.io.IOException;
  4 import java.sql.Connection;
  5 import java.sql.PreparedStatement;
  6 import java.sql.ResultSet;
  7 import java.sql.SQLException;
  8 import java.sql.Statement;
  9 import java.util.Properties;
 10 
 11 import javax.sql.DataSource;
 12 
 13 import org.apache.commons.dbcp2.BasicDataSourceFactory;
 14 import org.apache.log4j.Logger;
 15 
 16 /**
 17  * @version 0.1
 18  * @author Administrator
 19  * 
 20  */
 21 public class Dbcp_connection implements JdbcI {
 22     static Logger log = Logger.getLogger(Dbcp_connection.class);
 23     private Connection connection;
 24     /**
 25      * 在静态块中初始化获得DBCP数据源连接池
 26      */
 27     static {
 28         getDataSource();
 29         log.info("数据源已在静态块中初始化完成。");
 30     }
 31 
 32     /**
 33      *@return 返回Connection连接
 34      */
 35     public Connection getConnection() {
 36         if (connection == null || connection.equals("")) {
 37             try {
 38                 setConnection(getDataSource().getConnection());
 39                 log.info("从数据源中获取连接！");
 40                 return connection;
 41             } catch (SQLException e) {
 42                 log.error("对不起，数据库连接获取失败！");
 43                 e.printStackTrace();
 44             }
 45         }
 46         return null;
 47     }
 48     /**
 49      * @param sql    SQL语句
 50      * @return PrepaedStatement对象
 51      */
 52     public PreparedStatement getPStatement(String sql) {
 53         if (sql == null || sql.equals("")) {
 54             log.error("错误，SQL语句不允许为空!");
 55             return null;
 56         }
 57         PreparedStatement ps = null;
 58         try {
 59             ps = getConnection().prepareStatement(sql);
 60             log.info("SQL语句" + sql + "已经过预编译！");
 61             return ps;
 62         } catch (SQLException e) {
 63             log.error("异常，SQL语句" + sql + "预编译失败！");
 64             e.printStackTrace();
 65         }
 66 
 67         return null;
 68     }
 69 
 70     /**
 71      * 强制释放Connection连接。
 72      * 
 73      */
 74     public void close() {
 75         try {
 76             this.connection.close();
 77             log.info("Connection object" + this.connection.hashCode()
 78                     + "被强制释放！");
 79         } catch (SQLException e) {
 80             // TODO Auto-generated catch block
 81             e.printStackTrace();
 82         }
 83 
 84     }
 85 
 86      
 87     public void close(Statement ps) {
 88         // TODO Auto-generated method stub
 89         try {
 90          
 91             ps.close();
 92             this.connection.close();
 93             log.info("Statement（"
 94                     + ps.hashCode() + "），Connection("
 95                     + this.connection.hashCode() + ")已被释放！");
 96         } catch (SQLException e) {
 97             log.error("异常，JDBC对象关闭失败！");
 98             e.printStackTrace();
 99         }
100         
101     }
102     /**
103      * 按照顺序释放JDBC连接。
104      */
105     public void close(Statement ps, ResultSet rs) {
106         // TODO Auto-generated method stub
107         try {
108             rs.close();
109             ps.close();
110             this.connection.close();
111             log.info("ResultSet（" + rs.hashCode() + "），Statement（"
112                     + ps.hashCode() + "），Connection("
113                     + this.connection.hashCode() + ")已被释放！");
114         } catch (SQLException e) {
115             log.error("异常，JDBC对象关闭失败！");
116             e.printStackTrace();
117         }
118 
119     }
120 
121     public static void main(String[] args) {
122         // TODO Auto-generated method stub
123         /* 1 */
124         DataSource dds = getDataSource();
125         System.out.println(dds == null ? "数据源失败" : "数据源成功");
126 
127     }
128 
129     /**
130      * 全局公用的数据源
131      * 
132      * @return DataSource Object
133      */
134     private static DataSource getDataSource() {
135         String dbcpUrl = "dbcp-mysql.properties";
136 
137         DataSource ds;
138         Properties p = new Properties();
139         try {
140             // 通过类的类加载器将属性文件加载至输入流
141             p.load(JDBCUtil.class.getClassLoader().getResourceAsStream(dbcpUrl));
142             log.info("DBCP配置文件已加载！");
143 
144             ds = BasicDataSourceFactory.createDataSource(p);
145             log.info("数据源获取成功！");
146             return ds;
147 
148         } catch (IOException e) {
149             log.error("异常，可能是配置文件读取失败。");
150             e.printStackTrace();
151         } catch (Exception e) {
152             e.printStackTrace();
153         }
154 
155         return null;
156     }
157 
158     private void setConnection(Connection connection) {
159         log.info("获取连接，Hash地址为：" + connection.hashCode());
160         this.connection = connection;
161     }
162 
163     public DataSource getDS() {
164         // TODO Auto-generated method stub
165         log.info("数据源被外部调用！");
166         return getDataSource();
167     }
168 
169 }