java mysql

1.java操作mysql数据库，首先加入lib包，我本地使用的是mysql-connector-java-5.1.18-bin.jar

以下java代码例子：

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;


/*
 * mysql数据库操作
 * @@author
 * 创建时间：
 * 更新时间：
 * 
 */
public class DBhandle {
    
    private static String driver = "com.mysql.jdbc.Driver";
    private static String url = "jdbc:mysql://192.168.6.71:3306/";
    private static String db = "test";
    private static String character = "?useUnicode=true&characterEncoding=gbk";
    private static String user = "linchaojiang";
    private static String pass = "qwsSedcRFV";
     
    static Connection conn = null;
    static Statement statement = null;
    static PreparedStatement ps = null;
    static ResultSet rs = null;
    List<Map> list = new ArrayList<Map>();//返回所有记录
    
    /*
     * 连接数据库
     */    
     public static void connDB() {
          try {
           Class.forName(driver).newInstance();
           conn = DriverManager.getConnection(url+db+character, user, pass);
           if (!conn.isClosed()) {
            System.out.println("Succeeded connecting to MySQL!");
           }
           
           statement = conn.createStatement();
          } catch (Exception e) {
           e.printStackTrace();
          }
         }
        
    /*
     * 关闭数据库
     */
     public static void closeDB() {         
          if(rs != null ){              
              try {
                rs.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }              
          }          
          if(statement != null){              
              try {
                statement.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
          }
          if(conn != null){
           try {
            conn.close();
            System.out.println("Database connection terminated!");
           } catch (SQLException e) {
            e.printStackTrace();
               }
           }
         }             
     
     /*
      * 查询数据表
      */
     public List query(String sql){
        connDB();
        int count;
        try {
            rs = statement.executeQuery(sql);
            ResultSetMetaData rsmd;
            rsmd = rs.getMetaData();
            count = rsmd.getColumnCount();
            while(rs.next()){
                Map  map = new HashMap();
                for(int i=1;i<=count;i++){
                    //获取指定列的表目录名称
                    String label=rsmd.getColumnLabel(i);
                    //以 Java 编程语言中 Object 的形式获取此 ResultSet 对象的当前行中指定列的值
                    Object object= rs.getObject(i);
                    //把数据库中的字段名和值对应为一个map对象中的一个键值对
                    map.put(label.toLowerCase(), object);
                }
                list.add(map);                                         
            }            
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } finally {
            closeDB();
        }      
        return list;         
     }
     
     /*
      * 数据插入
      */
     public void insert(String sql){
            connDB(); 
            try {
                statement.execute(sql);
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }finally {
                closeDB();
            }     
     }
     
     /*
      * 数据更新
      */
     public void update(String sql){         
         connDB();
         try {
             statement.execute(sql);
         } catch (SQLException e) {
             // TODO Auto-generated catch block
             e.printStackTrace();
         }finally {
             closeDB();
         }         
     } 
     
     /*
      * 数据删除
      */
     public void delete(String sql){
         connDB();
         try {
             statement.execute(sql);
         } catch (SQLException e) {
             // TODO Auto-generated catch block
             e.printStackTrace();
         }finally {
             closeDB();
         }     
     }
}