第二十天，javaEE之sverlet

一、jdbc

package com.mysql;

import java.sql.Connection;
import java.sql.DriverManager;

public class MysqlZ {
	
	
	public Connection conn;
	
	public MysqlZ() {
		
		 try {
		      Class.forName("com.mysql.jdbc.Driver");     //加载MYSQL JDBC驱动程序   
		      //Class.forName("org.gjt.mm.mysql.Driver");
		      
		     System.out.println("Success loading Mysql Driver!");
		    }
		    catch (Exception e) {
		    	
		      System.out.print("Error loading Mysql Driver!");
		      e.printStackTrace();
		    }
		 try {
			 
			 conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/mydatabase01?useUnicode=true&characterEncoding=utf-8","root","123");
		           //连接URL为   jdbc:mysql//服务器地址/数据库名/字符集  ，后面的2个参数分别是登陆用户名和密码

		      System.out.println("Success connect Mysql server!");
		    }
		    catch (Exception e) {
		      System.out.print("get data error!");
		      e.printStackTrace();
		    }
	}
	
	public void close() {
        try {
            this.conn.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

}

二、增删改查方法

package com.mysql;

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

public class AddDelSercAlt {

//	public static void main(String[] args) {
//
//		
//		/*查找*/
//		List< Map<String,String> > maplist = new ArrayList<Map<String, String>>();
//		String sqlget = "select * from student";
//		
//		String[] params = {"Id","SName","Age","Sex","MathResult","EnglishResult","ChineseResult","Class"};
//		maplist = showNew(sqlget, params);
//		
//		for(int i = 0; i < maplist.size(); i++) {
//			String outstr = "Id:" + maplist.get(i).get("Id") 
//							+ "||SName:" + maplist.get(i).get("SName")
//							+ "||Age:" + maplist.get(i).get("Age")
//							+ "||Sex:" + maplist.get(i).get("Sex")
//							+ "||MathResult:" + maplist.get(i).get("MathResult")
//							+ "||EnglishResult:" + maplist.get(i).get("EnglishResult")
//							+ "||ChineseResult:" + maplist.get(i).get("ChineseResult")
//							+ "||Class:" + maplist.get(i).get("Class");
//							
//			System.out.println(outstr);
//		}
//	
//	}
	
	
	 //插入操作
    public static int add(String sqll) {
        
    	int i=0;
        MysqlZ db = new MysqlZ();   //new一个连接数据库对象
        
        try {        
            PreparedStatement preStmt = (PreparedStatement) db.conn.prepareStatement(sqll);
            preStmt.executeUpdate();
            
            System.out.println("insert secced !");
            preStmt.close();  //关闭写入
            db.close();//关闭连接 
            
            i = 1;
            
        } catch (Exception e) {
            e.printStackTrace();
        }
        return i;//返回影响的行数，1为执行成功
    }
    
    
    
    
    
    //旧的查找操作
    public static void showOld(){
         String sql ="select * from employee";
         MysqlZ db = new MysqlZ();
         
         System.out.println("-----------------");
         System.out.println("姓名" +"\t"+ "邮箱" +"\t"+ "日期");
         System.out.println("-----------------");
         
         try {
            Statement stmt = (Statement) db.conn.createStatement();
            ResultSet rs = (ResultSet) stmt.executeQuery(sql);
            
            while(rs.next()){
                String uname = rs.getString("name");
                String uemail = rs.getString("email");
                String uhiredate = rs.getString("hiredate");
                //可以将查找到的值写入类，然后返回相应的对象 
                //这里 先用输出的端口显示一下
                System.out.println(uname +"\t"+ uemail +"\t"+ uhiredate);
            }
            rs.close();
            db.close();//关闭连接 
        } catch (SQLException e) {
            e.printStackTrace();
        } 
    }
    
    
    
    /****************新的查找********************/
    public static List< Map<String,String> > showNew(String sql, String[] params){
    	
    	List< Map<String,String> > listmap = new ArrayList<Map<String, String>>();
    	
    	MysqlZ db = new MysqlZ();
        ResultSet rs = null;
         
        try {
			Statement stmt = (Statement) db.conn.createStatement();
			rs = (ResultSet) stmt.executeQuery(sql);
			   
			while(rs.next()){
				
				Map<String,String> map = new HashMap<String,String>();
				
				for(int i = 0; i < params.length; i++) {
					map.put(params[i], rs.getString(params[i]));
				}
				listmap.add(map);
			}
			
			rs.close();
			db.close();
			
        } catch (SQLException e) {
            e.printStackTrace();
        }
		
		return listmap; 
         
    }


    
    //更新操作
    public static int update(String sqll) {
        int i =0;
        MysqlZ db = new MysqlZ();
        
        try {
            PreparedStatement preStmt = (PreparedStatement) db.conn.prepareStatement(sqll);
            preStmt.executeUpdate();
            
            preStmt.close();
            db.close();//关闭连接 
            
            i = 1;
            
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return i;//1为执行成功
    }
    
    
    
    
    
    
    //删除操作
    public static int del(String sqll) {
        int i=0;

        MysqlZ db = new MysqlZ();
        try {    
            PreparedStatement preStmt = (PreparedStatement) db.conn.prepareStatement(sqll);
            preStmt.executeUpdate();
            
            preStmt.close();
            db.close();//关闭连接 
            
            i = 1;
        } catch (SQLException e){
            e.printStackTrace();
        }
        return i;//1为执行成功
    }

}

三、ajax

            $.ajax({
			        type: "post",
			        url: url,
			        data: data,
			        cache: false,
			        async : false,
			        success: function (data ,textStatus, jqXHR){
			        	if(data.code == 200){
			        		alert("插入成功了");
			        	}else{
			        		alert(data.message);
			        	}
			        },
			        error:function (XMLHttpRequest, textStatus, errorThrown) {      
			           
			            alert(typeof(errorThrown));
			        }
		     });

四、百度服务器里的jQuery

<script src="http://libs.baidu.com/jquery/2.0.0/jquery.min.js"></script>

五、sverlet的dopost方法

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		response.setCharacterEncoding("utf-8");
		response.setContentType("application/json; charset=utf-8");
		
		String SName = request.getParameter("SName");
		String Age = request.getParameter("Age");
		String Sex = request.getParameter("Sex");
		String MathResult = request.getParameter("MathResult");
		String EnglishResult = request.getParameter("EnglishResult");
		String ChineseResult = request.getParameter("ChineseResult");
		String Class = request.getParameter("Class");
		
		String sqlInsert = "insert into student(SName,Age,Sex,MathResult,EnglishResult,ChineseResult,Class)"
				+"values('"+SName+"',"+Age+","+Sex+","+MathResult+","+EnglishResult+","+ChineseResult+",'"+Class+"')";
		
		
		int flag = AddDelSercAlt.add(sqlInsert);
		
		String resposeMessage = "";
		
		if(flag == 1){
			System.out.println("Insert成功");
			resposeMessage = "{\"cood\":200,\"message\":\"成功插入\"}";
		}else{
			System.out.println("Insert失败");
			resposeMessage = "{\"cood\":999,\"message\":\"插入失败\"}";
		}
		
		response.getWriter().write(resposeMessage);
		
	}