每日总结 4..9

今天对我的售卖机页面设计。

 实现androd的数据传输，和补货的数据更新。

package com.example.jjt;
import android.util.Log;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;


public class Dbhelper {
    private static Connection connection;
    private final static String driver = "com.mysql.jdbc.Driver";
    private final static String url = "jdbc:mysql://10.99.121.119/jiaqi?useUnicode=true&characterEncoding=UTF-8";
    private final static String user = "root";
    private final static String pass= "020907";

    Connection conn=null;
    Statement st=null;
    ResultSet rs=null;

    static {
        try {
            Class.forName(driver);
        } catch (ClassNotFoundException e) {
            System.out.println("加载驱动错误");
        }
    }


    //2. 获取连接
    public static Connection getConnect() {
        try {
            connection=DriverManager.getConnection(url,user,pass);
        }catch(SQLException e) {
            e.printStackTrace();
        }
        return connection;
    }
    //3. 释放连接资源

    public static void release(Connection conn, Statement st, ResultSet rs) throws Exception {
        if (rs != null) {
            rs.close();
        }
        if (st != null) {
            st.close();
        }
        if (conn != null) {
            conn.close();
        }
    }
    public static String getInfoByName(String name){
        String s="";
        // 根据数据库名称，建立连接
        Connection connection = getConnect();

        try {
            // mysql简单的查询语句。这里是根据MD_CHARGER表的NAME字段来查询某条记录
            String sql = "select * from thing where name = ?";
//            String sql = "select * from MD_CHARGER";
            if (connection != null){// connection不为null表示与数据库建立了连接
                PreparedStatement ps = connection.prepareStatement(sql);
                if (ps != null){
                    // 设置上面的sql语句中的？的值为name
                    ps.setString(1, name);
                    // 执行sql查询语句并返回结果集
                    ResultSet rs = ps.executeQuery();
                    if (rs != null){
                        int count = rs.getMetaData().getColumnCount();
                        Log.e("DBUtils","列总数：" + count);
                        while (rs.next()){
                            // 注意：下标是从1开始的
                            s= rs.getString("total");
                        }
                        connection.close();
                        ps.close();
                        return  s;
                    }else {
                        return null;
                    }
                }else {
                    return  null;
                }
            }else {
                return  null;
            }
        }catch (Exception e){
            e.printStackTrace();
            Log.e("DBUtils","异常：" + e.getMessage());
            return null;
        }
    }
    public static String fins(String name){
        String s="";
        // 根据数据库名称，建立连接
        Connection connection = getConnect();

        try {
            // mysql简单的查询语句。这里是根据MD_CHARGER表的NAME字段来查询某条记录
            String sql = "select * from thing where name = ?";
//            String sql = "select * from MD_CHARGER";
            if (connection != null){// connection不为null表示与数据库建立了连接
                PreparedStatement ps = connection.prepareStatement(sql);
                if (ps != null){
                    // 设置上面的sql语句中的？的值为name
                    ps.setString(1, name);
                    // 执行sql查询语句并返回结果集
                    ResultSet rs = ps.executeQuery();
                    if (rs != null){
                        int count = rs.getMetaData().getColumnCount();
                        Log.e("DBUtils","列总数：" + count);
                        while (rs.next()){
                            // 注意：下标是从1开始的
                            s= rs.getString("num");
                        }
                        connection.close();
                        ps.close();
                        return  s;
                    }else {
                        return null;
                    }
                }else {
                    return  null;
                }
            }else {
                return  null;
            }
        }catch (Exception e){
            e.printStackTrace();
            Log.e("DBUtils","异常：" + e.getMessage());
            return null;
        }
    }
}