如何在Android中使用Jackson解析器处理JSON数组解析

Question

Here is my structure of json data. It has huge amount of data similarly to this. I am using Jackson parser for parsing this.

{
 "dealers":
 {
  "google.com":{"id":1,"merchantname":"google","status":"active"},
  "apple.com":{"id":2,"merchantname":"apple","status":"active"}
 }
}

Code:

    while (jParser.nextToken() != JsonToken.END_OBJECT) {
            jParser.nextToken();

            while (jParser.nextToken() != JsonToken.END_OBJECT) {
                jParser.nextToken();

                while (jParser.nextToken() != JsonToken.END_OBJECT) {
                    jParser.nextToken();
                    String fieldname = jParser.getCurrentName();
                    if (fieldname != null) {

                        if ("id".equals(fieldname)) {
                            jParser.nextToken();
                            if (jParser.getText() != null)
                                merchantID = jParser.getText();
                            else
                                merchantID = "";
                        }

                        if ("merchantname".equals(fieldname)) {
                            jParser.nextToken();
                            if (jParser.getText() != null)
                                merchantname = jParser.getText();
                            else
                                merchantname = "";
                        }

                        if ("status".equals(fieldname)) {
                            jParser.nextToken();
                            if (jParser.getText() != null)
                                name = jParser.getText();
                        }

                    }

                }
            }
        }

The data is not parsed properly. Messed up with the jParser.nextToken() methods. Can anyone point out the mistake here?

Answer 1

"dealers" property in JSON represents Map<String, POJO_CLASS> . You can easily convert it to below POJO classes:

class RootEntity {

    private Map<String, Entity> dealers;

    //getters,setters, toString
}

class Entity {

    private int id;
    private String merchantname;
    private String status;

    //getters,setters, toString
}

Example usage:

import java.io.File;
import java.io.IOException;
import java.util.Map;

import com.fasterxml.jackson.databind.ObjectMapper;

public class JacksonProgram {

    public static void main(String[] args) throws IOException {
        ObjectMapper mapper = new ObjectMapper();
        System.out.println(mapper.readValue(new File("/data/x.json"), RootEntity.class));
    }
}

prints:

RootEntity [dealers={google.com=Entity [id=1, merchantname=google, status=active], apple.com=Entity [id=2, merchantname=apple, status=active]}]