AS Jackson編②～ObjectMapper（Jackson）を使う［MapをJSONファイルへ変換］

MainActivity.javaと、activity_main.xmlは前回（ObjectMapperを使う①）と同じです。

SecondActivity.java

package com.example.mapjsondemo;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.util.Log;

import com.fasterxml.jackson.core.JsonGenerationException;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.ObjectMapper;

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

public class SecondActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_second);

        try {

            ObjectMapper mapper = new ObjectMapper();
            String json = "";

            Map<String, Object> map = new HashMap<String, Object>();
            map.put("name", "yamada");
            map.put("age", 29);

            json = mapper.writerWithDefaultPrettyPrinter().writeValueAsString(map);

            //pretty print
            Log.v("MY_LOG",json);

        } catch (JsonGenerationException e) {
            e.printStackTrace();
        } catch (JsonMappingException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

activity_second.xml

デフォルトのままです。

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".SecondActivity">

</androidx.constraintlayout.widget.ConstraintLayout>

これまでどおり、build.gradleのdependencies内の記載もしてます。