springMvc04(json数据传递参数)

一、集合参数（JSON格式）

1.1-导入"JSON"坐标（通用设置一次就可以）

<!-- springmvc 需要的json相关坐标-->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.12.0</version>
        </dependency>

1.2-在"config-->springMvcConfig"加入@EnableWebMvc注解（通用设置一次就可以）

1.3-外部按照JSON格式的数据传入：["aaa","bbb","ccc"]

1.4-在"行参"里面加入@RequestBody注解

二、POJO参数(json格式)：实体类

2.1-外部按照JSON格式的数据传入：

{
    "name":"chenxiix",
    "age":"18",
    "address":{
        "province":"beijing",
        "city":"beijing"
    }
}

2.2-PostMan测试：外部按照JSON格式的数据传入：

2.3-在"行参"里面加入@RequestBody注解

User这个实体类的代码块

public class User {

    private String name;

    @Override
    public String toString() {
        return "User{" +
                "name='" + name + '\'' +
                ", age=" + age +
                ", address=" + address +
                '}';
    }

    private int age;
    private Address address;

    public Address getAddress() {
        return address;
    }

    public void setAddress(Address address) {
        this.address = address;
    }


    public User(String name, int age) {
        this.name = name;
        this.age = age;
    }

    public User() {
    }



    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }
}

嵌套的实体类Address代码块

public class Address {
    private String province ;
    private String city;

    @Override
    public String toString() {
        return "Address{" +
                "province='" + province + '\'' +
                ", city='" + city + '\'' +
                '}';
    }

    public String getProvince() {
        return province;
    }

    public void setProvince(String province) {
        this.province = province;
    }

    public String getCity() {
        return city;
    }

    public void setCity(String city) {
        this.city = city;
    }
}

三、"集合"中有多个对象

3.1-外部按照JSON格式的数据传入：

[
    {"name":"chenxixi","age":"18" ,
    "addrsss":{"province":"beijng","city":"beijing"}
    },


    {"name":"wangwang","age":"18" ,
    "addrsss":{"province":"beijng","city":"beijing"}
    }
   
]

3.2-PostMan测试：（外部按照JSON格式的数据传入）

3.3-在"行参"里面加入@RequestBody注解：

User这个实体类的代码块

public class User {

    private String name;

    @Override
    public String toString() {
        return "User{" +
                "name='" + name + '\'' +
                ", age=" + age +
                ", address=" + address +
                '}';
    }

    private int age;
    private Address address;

    public Address getAddress() {
        return address;
    }

    public void setAddress(Address address) {
        this.address = address;
    }


    public User(String name, int age) {
        this.name = name;
        this.age = age;
    }

    public User() {
    }



    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }
}

嵌套的实体类Address代码块

public class Address {
    private String province ;
    private String city;

    @Override
    public String toString() {
        return "Address{" +
                "province='" + province + '\'' +
                ", city='" + city + '\'' +
                '}';
    }

    public String getProvince() {
        return province;
    }

    public void setProvince(String province) {
        this.province = province;
    }

    public String getCity() {
        return city;
    }

    public void setCity(String city) {
        this.city = city;
    }
}

四、总结；

4.1：本节的主要三个"JSON"参数

4.2：步骤1，导入json坐标

4.3：步骤2，设置发生JSON数据

4.4：步骤3，开启自动转换JSON数据支持

4.5：步骤4:，设置接收JSON数据

4.6：结尾

、

五、附加：注解介绍

5.1：@EnableWebMvc

5.2：@RequestBody

5.3：@RequestBody和@RequestParam的区别

六、代码块总结

 //集合参数(json格式)
    @RequestMapping("/listParamForJson")
    @ResponseBody
    public String listParamForJson(@RequestBody List<String> likes) { //需要以JSON格式传入数据
        System.out.println("--> 集合参数(json类型)listParamForJson：" + likes);
        System.out.println("--------");
        return "{molder:user_CommonParam}";
    }

    //POJO参数(json格式)：实体类
    @RequestMapping("/pojoParamForJson")
    @ResponseBody
    public String pojoParamForJson(@RequestBody User user) { //需要以JSON格式传入数据
        System.out.println("--> POJO参数(json类型)POJOParamForJson：" + user);
        System.out.println("--------");
        return "{molder:user_CommonParam}";
    }

    //POJO参数(json格式)：实体类
    @RequestMapping("/listPojoParamForJson")
    @ResponseBody
    public String listPojoParamForJson(@RequestBody List<User> list) { //多个"实体类"
        System.out.println("--> listPojoParamForJson参数(json类型)POJOParamForJson：" + list);
        System.out.println("--------");
        return "{molder:user_CommonParam}";
    }