JavaWeb关于AJAX的使用
关于AJAX的使用
最近做了一个用人脸识别进行登录注册的Javaweb项目，其中用到了用AJAX进行登录识别的问题，源码如下
人脸识别的后端源码
package com.rain.servlet;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.Base64;
import java.util.HashMap;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import org.json.JSONObject;
import java.util.Base64.Decoder;
import com.baidu.aip.face.AipFace;
import com.rain.bean.AdminBean;
import com.rain.dao.AdminDao;
public class FaceServlet extends HttpServlet {
/**
*
*/
private static final long serialVersionUID = 1L;
/**
* (非 Javadoc)
* Description(描述):get方法，主要调用post
* Title: doGet
* @param request
* @param response
* @throws ServletException
* @throws IOException
* @see javax.servlet.http.HttpServlet#doGet(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request, response);
}
/**
* (非 Javadoc)
* Description(描述):post方法，主要进行业务操作
* Title: doPost
* @param request
* @param response
* @throws ServletException
* @throws IOException
* @see javax.servlet.http.HttpServlet#doPost(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
*/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
//防止乱码
response.setContentType("text/html;charset=utf-8");
request.setCharacterEncoding("utf-8");
response.setCharacterEncoding("utf-8");
String img=request.getParameter("img"); //图像数据
String username = request.getParameter("username");
String name=request.getParameter("name");
String password=request.getParameter("password");//用户名
String email = request.getParameter("email");
String phone = request.getParameter("phone");
String status=request.getParameter("status");
String tag = request.getParameter("tag");
//System.out.println(status);
String APP_ID = "11199968";
String API_KEY = "s38ErHUzrxr915bt6lYGlv8V";
String SECRET_KEY = "BQsbuqDgaIcdIzCceg3fwUTDEcrFFWWR";
AipFace client = new AipFace(APP_ID, API_KEY, SECRET_KEY);
if(tag.equals("reg")){
//注册
face(username, img,name,password,email,phone, response,request,client);
}else if(tag.endsWith("login")){
//登陆
login(status,img,response,username,password,request,client);
}
}
public void face(String username ,String img,String name,String password,String email,String phone,HttpServletResponse response,HttpServletRequest request,AipFace client) {
AdminBean adm = new AdminBean();
//IUserService userService = new UserServiceImpl();
// 图片名称
// 往数据库里面插入注册信息
String fileName = System.currentTimeMillis() + ".png";
String basePath = request.getSession().getServletContext().getRealPath("picture/");
//String username1 = request.getParameter("username");
//String password = request.getParameter("password");
//String name = request.getParameter("name");
//String email = request.getParameter("email");
//String phone = request.getParameter("phone");
int lend_num = 30;
int max_num = 5;
AdminDao userdao = new AdminDao();
//将注册信息存入数据库，再返回登录
userdao.Register(username,name,password,email,phone,lend_num,max_num);
// 往服务器里面上传图片
GenerateImage(img, basePath+ "/" + fileName);
// 给人脸库中加入一个脸
boolean flag = facesetAddUser(client, basePath + "/" + fileName,
username);
try {
PrintWriter out = response.getWriter();
// 中文乱码，写个英文比较专业 哈哈
if (flag == false) {
out.print("请把脸放上!!");//请把两脸放上
} else {
out.print("注册成功!!"); //注册成功
//response.sendRedirect("/books/login.jsp");
}
} catch (IOException e) {
// TODO 异常执行块！
e.printStackTrace();
}
}
/**
*
* @Title: login
* @Description: 该方法的主要作用：登陆
* 实现原理：
* 1.从前台接收用户名
* 2.然后把从前台传过来的图片先上传到服务器
* 3.把上传的这张人脸与人脸库中的人脸对应
* @param 设定文件
* @return 返回类型：String
* @throws
*/
public void login(String status,String img,HttpServletResponse response,String username,String password,HttpServletRequest request,AipFace client) {
// 图片名称
String fileName = System.currentTimeMillis() + ".png";
String basePath = request.getSession().getServletContext()
.getRealPath("picture/");
// 往服务器里面上传图片
GenerateImage(img, basePath + "/" + fileName);
response.setContentType("text/html,charset=utf-8;");
AdminBean adminbean = new AdminBean();
AdminDao admindao = new AdminDao();
try {
PrintWriter out = response.getWriter();
//String result1 = admindao.Login_verify(status);
HttpSession session = request.getSession();
Double result = verifyUser(client, basePath + "/" + fileName,username);
if (result > 90) {
adminbean = admindao.getAdminInfo(username);
session.setAttribute("aid", ""+adminbean.getAid());
//设置session的失效时间
session.setMaxInactiveInterval(6000);
// 匹配成功
int n = Integer.parseInt(adminbean.getStatus());
if(n==1){
out.print("1");
//out.flush();
//out.close();
//response.sendRedirect("index2.jsp;
//return;
//
}else if(n==2){
out.print("2");
//out.flush();
//out.close();
//response.sendRedirect("admin.jsp");
//return;
}
} else {
out.print("3");
//out.flush();
//out.close();
}
} catch (IOException e) {
// TODO 异常执行块！
e.printStackTrace();
}
}
servlet返回数据给ajax的时候用的是out.print
status的值定义的是管理员权限
out.print(“1”)对应index2.jsp
out.print(“2”)对应admin.jsp
人脸登录的源码
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" %>
图书馆登录
选择主题
调用了AJAX方法，响应了Servlet中的out.print()方法，实现了登录验证功能
通常情况下我们会通sendRedirect方法进行重定向而跳转页面，而此方法只需要判断Status的值，从而解决了页面跳转问题。