目标

通过ajax向服务器传递json格式的数据
服务器接收json格式的数据后, 返回json格式的数据

单个对象的json格式数据, json数组对象

视图

纯html页面文件view/index.html(根据配置文件中静态资源映射设置, 实际目录是p/index.html)内容如下:

<!DOCTYPE html>
<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
        <title>JSP Page</title>
        <script type="text/javascript" src="jquery-3.3.1.min.js"></script>
        <script type="text/javascript">
            function send1_OnClicked() {
                var account = {};
                account['accountID'] = "62001";
                account['balance'] = 100;
                $.ajax({
                    type: "POST",
                    url: "../rest/getjson1",
                    dataType: "json",
                    contentType: "application/json",
                    data: JSON.stringify(account),
                    success: function (data) {
                        var account = data;
                        $("#account").html(account.accountID + ":" + account.balance);
                    },
                    error: function (data) {
                        console.log("error...");
                        console.log(data);
                    }
                });
            }
            function send2_OnClicked() {
                var account = {};
                account['accountID'] = "62002";
                account['balance'] = 200;
                console.log(JSON.stringify(account));
                $.ajax({
                    type: "POST",
                    url: "../rest/getjson2",
                    dataType: "json",
                    contentType: "application/json",
                    data: JSON.stringify(account),
                    success: function (data) {
                        var account = data;
                        $("#account").html(account.accountID + ":" + account.balance);
                    },
                    error: function (data) {
                        console.log("error...");
                        console.log(data);
                    }
                });
            }
            function send3_OnClicked() {
                var accounts = [];
                var account1 = {"accountID": "62001", "balance": "100"};
                var account2 = {"accountID": "62002", "balance": "200"};
                var account3 = {"accountID": "62003", "balance": "300"};
                accounts.push(account1);
                accounts.push(account2);
                accounts.push(account3);
                console.log(JSON.stringify(accounts));
                $.ajax({
                    type: "POST",
                    url: "../rest/getjson3",
                    dataType: "json",
                    contentType: "application/json",
                    data: JSON.stringify(accounts),
                    success: function (data) {
                        var account = data;
                        $("#account").html(account.accountID + ":" + account.balance);
                    },
                    error: function (data) {
                        console.log("error...");
                        console.log(data);
                    }
                });
            }
            function send4_OnClicked() {
                var accounts = [];
                var account1 = {"accountID": "62001", "balance": "100"};
                var account2 = {"accountID": "62002", "balance": "200"};
                var account3 = {"accountID": "62003", "balance": "300"};
                var account4 = {"accountID": "62004", "balance": "400"};
                accounts.push(account1);
                accounts.push(account2);
                accounts.push(account3);
                accounts.push(account4);
                $.ajax({
                    type: "POST",
                    url: "../rest/getjson4",
                    dataType: "json",
                    contentType: "application/json",
                    data: JSON.stringify(accounts),
                    success: function (data) {
                        $("#account").html(data.accounts.length + ":" + data.accounts[0].accountID + ":" + data.accounts[0].balance);
                    },
                    error: function (data) {
                        console.log("error...");
                        console.log(data);
                    }
                });
            }
        </script>
    </head>
    <body>
        <h1 id ="account">Hello World!</h1>
        <input type="button" value="send1" onclick="send1_OnClicked()" />
        <input type="button" value="send2" onclick="send2_OnClicked()" />
        <input type="button" value="send3" onclick="send3_OnClicked()" />
        <input type="button" value="send4" onclick="send4_OnClicked()" />
    </body>
</html>

控制器

需要下载三个jackson的jar文件, 加入到项目中, 用于处理json数据. 下载链接https://pan.baidu.com/s/1wqEz-QSfvwL_WB18z0B_uA
文件controller/DemoRestController.java内容如下:

package controller;

import java.util.List;
import model.Account;
import model.AccountList;
import org.springframework.http.HttpEntity;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@RequestMapping("/rest")
public class DemoRestController {

    @RequestMapping(value = "/getjson1", produces = {"application/json;charset=UTF-8"})
    public Account getjson1(@RequestBody Account account) {
        System.out.println(account.getAccountID() + ":" + account.getBalance());
        return new Account(account.getAccountID() + "getjson1测试", account.getBalance() + 200);   
    }

    @RequestMapping(value = "/getjson2", produces = {"application/json;charset=UTF-8"})
    public Account getjson2(HttpEntity<Account> httpEntity) { 
        Account account = httpEntity.getBody();
        System.out.println(account.getAccountID() + ":" + account.getBalance());
        return new Account(account.getAccountID() + "getjson12测试", account.getBalance() + 200);
    }

    @RequestMapping(value = "/getjson3", produces = {"application/json;charset=UTF-8"})
    public Account getjson3(@RequestBody List<Account> accounts) {
        accounts.stream().forEach((account) -> {
            System.out.println(account.getAccountID() + ":" + account.getBalance());
        });
        return new Account(accounts.get(0).getAccountID() + "getjson3", accounts.get(0).getBalance() + 200);
    }

    @RequestMapping(value = "/getjson4", produces = {"application/json;charset=UTF-8"})
    public AccountList getjson4() {
        AccountList accounts = new AccountList();
        for (int i = 0; i < 10; i++) {
            accounts.getAccounts().add(new Account("getjson4" + i + Math.random(), (int) (Math.random() * 1000)));
        }
        return accounts;
    }
}

模型

文件model/Account.java内容如下:

package model;
public class Account {
    private String accountID;
    private int balance;

    public Account() {
    }

    public Account(String accountID) {
        this.accountID = accountID;
    }

    public Account(String accountID, int balance) {
        this.accountID = accountID;
        this.balance = balance;
    }

    public int getBalance() {
        return balance;
    }

    public void setBalance(int balance) {
        this.balance = balance;
    }

    public String getAccountID() {
        return accountID;
    }

    public void setAccountID(String accountID) {
        this.accountID = accountID;
    }
}

文件model/AccountList.java内容如下:

package model;

import java.util.ArrayList;
import java.util.List;

public class AccountList {
    private List<Account> accounts;

    public AccountList() {
        this.accounts = new ArrayList<>();
    }

    public AccountList(List<Account> accounts) {
        this.accounts = accounts;
    }

    public List<Account> getAccounts() {
        return accounts;
    }

    public void setAccounts(List<Account> accounts) {
        this.accounts = accounts;
    }
}

配置文件

配置文件config/SpringMvcInitializer,java内容如下:

package config;

import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRegistration;
import org.springframework.web.WebApplicationInitializer;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
import org.springframework.web.servlet.DispatcherServlet;

public class SpringMvcInitializer implements WebApplicationInitializer {  //实现这个接口是关键, 与类名无关.

    @Override
    public void onStartup(ServletContext sc) throws ServletException {
        AnnotationConfigWebApplicationContext context = new AnnotationConfigWebApplicationContext();
        context.register(AppConfig.class); //自己定义的AppConfig类.
        context.setServletContext(sc);
        ServletRegistration.Dynamic servlet = sc.addServlet("dispatcher", new DispatcherServlet(context));
        servlet.addMapping("/");
        servlet.setLoadOnStartup(1);
    }
}

配置文件config/AppConfig.java内容如下:

package config;

import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;

@Configuration
@EnableWebMvc
@ComponentScan(basePackages = {"controller"})
public class AppConfig extends WebMvcConfigurerAdapter {

    @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
        registry.addResourceHandler("/view/**").addResourceLocations("/p/"); //静态资源映射
        registry.addResourceHandler("/index.html").addResourceLocations("/index.html"); //静态资源映射
    }
}