通讯录查询项目--通过id以及通过邮箱查询_如何核实邮件联系人为有效联系人-优快云博客

本文链接：https://blog.youkuaiyun.com/AKABUGmaker/article/details/101623511

本文介绍了通过HTTP Servlet实现的两种联系人查询方法：一种是通过ID查询指定联系人，并将其转发到更新页面；另一种是通过邮箱查询联系人是否存在，返回JSON格式的查询结果。

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通过id查询:

public class QueryByIdServlet extends HttpServlet {
    ContactServiceImpl contactService = new ContactServiceImpl();
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        request.setCharacterEncoding("utf-8");
        response.setContentType("text/html;charset=utf-8");


        //通过id查询指定对象
        String id = request.getParameter("id");
        //通过传过来的id参数获得要查找的对象
        Contact contact = contactService.query(id);
        //将contact放入请求域中
        request.setAttribute("contact",contact);
        //因为要发送查找后的资源,用重定向技术发送
        request.getRequestDispatcher("update.jsp").forward(request,response);

    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        this.doPost(request, response);
    }
}

通过邮箱查询

public class QueryEmailServlet extends HttpServlet {
    ContactServiceImpl contactService = new ContactServiceImpl();
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        request.setCharacterEncoding("utf-8");
        response.setContentType("application/json;charset=utf-8");
        String email = request.getParameter("email");
        boolean exist = contactService.queryByEmail(email);
        PrintWriter out = response.getWriter();
        Map<String,Object> responseObj = new HashMap<>();

        if(exist){
            //存在
            responseObj.put("code",1);
            responseObj.put("error","此邮箱已经存在!");
        }else {
            //不存在
            responseObj.put("code",0);
            responseObj.put("error","此邮箱不存在,可以注册");
        }

        ObjectMapper mapper = new ObjectMapper();
        String s = mapper.writeValueAsString(responseObj);
        out.write(s);


    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        this.doPost(request, response);
    }
}