常用json框架介绍和Jackson返回结果处理

简介：介绍常用json框架和注解的使用，自定义返回json结构和格式

1、常用框架 阿里 fastjson,谷歌gson等
JavaBean序列化为Json，性能：Jackson > FastJson > Gson > Json-lib 同个结构
Jackson、FastJson、Gson类库各有优点，各有自己的专长
空间换时间，时间换空间

2、jackson处理相关自动
指定字段不返回：@JsonIgnore
指定日期格式：@JsonFormat(pattern="yyyy-MM-dd hh:mm:ss",locale="zh",timezone="GMT+8")
空字段不返回：@JsonInclude(Include.NON_NUll)
指定别名：@JsonProperty

实体类代码如下：

 

public class rData {
    
    @JsonIgnore
    private String code;

    @JsonProperty(value = "agenum")
    private int age;

    @JsonFormat(pattern="yyyy-MM-dd hh:mm:ss",locale="zh",timezone="GMT+8")
    private Date createDate;

    @JsonInclude(JsonInclude.Include.NON_NULL)
    private String name;

    public String getName() {
        return name;
    }

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

    public Date getCreateDate() {
        return createDate;
    }

    public void setCreateDate(Date createDate) {
        this.createDate = createDate;
    }

    public int getAge() {
        return age;
    }

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

    public String getCode() {
        return code;
    }

    public void setCode(String code) {
        this.code = code;
    }
    
    public rData(String code, int age) {
        this.code = code;
        this.age = age;
    }

    public rData(String code, int age, Date createDate, String name) {
        this.code = code;
        this.age = age;
        this.createDate = createDate;
        this.name = name;
    }
}

 

测试类代码：

@RestController
public class HttpController {

    @GetMapping("/testjson")
    public Object param6(){
        return new rData("jackson",1,new Date(),"lion");
    }

}

结果：

{"createDate":"2018-09-18 09:36:31","name":"lion","agenum":1}

code被忽略了，所以不显示；age被别名代替"agenum"