Serialization in jackson is the use of annotations in Json

@JsonSerialize ( include =   JsonSerialize .Inclusion. NON_NULL )
 //When json is serialized, if it is a null object , the key will disappear
 public class PicUploadResult {
     // The judgment flag of whether the upload is successful, 0- success, 1- failure
 private Integer error ;
     private String url ;
     private String message ;
 @JsonIgnore
 // make it not in the json serialization result
 private String width ;
 @JsonIgnore
    


            
        private String height;
    public PicUploadResult(){


    }

    public Integer getError() {
        return error;
    }

    public void setError(Integer error) {
        this.error = error;
    }

    public String getUrl() {
        return url;
    }

    public void setUrl(String url) {
        this.url = url;
    }

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }

    public String getWidth() {
        return width;
    }

    public void setWidth(String width) {
        this.width = width;
    }

    public String getHeight() {
        return height;
    }

    public void setHeight(String height) {
        this.height = height;
    }
}