dbutil.java

这是中国移动的一个管理系统

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

package com.mobile.util;

import java.sql.Statement;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 *
 * @author st
 */
public class DBUtil {
     static {
        try {
            Class.forName("com.mysql.jdbc.Driver");
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
    }

    public static Connection getConnection() {
        Connection conn = null;
        String url = ProperManagerUtil.getValue("url");
        String dbName = ProperManagerUtil.getValue("dbname");
        String dbPwd = ProperManagerUtil.getValue("dbpwd");
        try {
            conn = DriverManager.getConnection(url, dbName, dbPwd);
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return conn;
    }

    public static void close(ResultSet rs, Statement stmt, Connection conn) {
        try {
            if (rs != null) {
                rs.close();
                rs = null;
            }
            if (stmt != null) {
                stmt.close();
                stmt = null;
            }
            if (conn != null) {
                conn.close();
                conn = null;
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }

    }

    public static int update(PreparedStatement stmt, String sql) {
        int rs = -1;
        try {

            rs = stmt.executeUpdate(sql);
        } catch (SQLException ex) {
            Logger.getLogger(DBUtil.class.getName()).log(Level.SEVERE, null, ex);
        }
        return rs;
    }

    public static ResultSet query(Statement stmt, String sql) {
        ResultSet rs = null;
        try {
            rs = stmt.executeQuery(sql);
        } catch (SQLException ex) {
            Logger.getLogger(DBUtil.class.getName()).log(Level.SEVERE, null, ex);
        }
        return rs;
    }

    public static void main(String[] args) {
        Connection conn = null;
        Statement stmt = null;
        ResultSet rs = null;

        try {
            conn = getConnection();
            stmt = conn.createStatement();
            String sql = "select * from TOperator";
            rs = query(stmt, sql);
            while (rs.next()) {
                System.out.println(rs.getString(1));
            }

        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            close(rs, stmt, conn);

        }



    }

}