Androidでjsonデータを解析、生成する

2014年8月23日

1.jsonを解析
package com.startnews24.android.twitter.json;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.StatusLine;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONArray;
import org.json.JSONObject;

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

public class ParseJSON extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
String readTwitterFeed = readTwitterFeed();
try {
JSONArray jsonArray = new JSONArray(readTwitterFeed);
Log.i(ParseJSON.class.getName(),
“エントリの数： " + jsonArray.length());
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject jsonObject = jsonArray.getJSONObject(i);
Log.i(ParseJSON.class.getName(), jsonObject.getString(“text"));
}
} catch (Exception e) {
e.printStackTrace();
}
}

public String readTwitterFeed() {
StringBuilder builder = new StringBuilder();
HttpClient client = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(
“http://twitter.com/statuses/user_timeline/vogella.json");
try {
HttpResponse response = client.execute(httpGet);
StatusLine statusLine = response.getStatusLine();
int statusCode = statusLine.getStatusCode();
if (statusCode == 200) {
HttpEntity entity = response.getEntity();
InputStream content = entity.getContent();
BufferedReader reader = new BufferedReader(
new InputStreamReader(content));
String line;
while ((line = reader.readLine()) != null) {
builder.append(line);
}
} else {
Log.e(ParseJSON.class.toString(), “ファイルのダウンロードに失敗しました");
}
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return builder.toString();
}
}

2.jsonを生成
public void writeJSON() {
JSONObject object = new JSONObject();
try {
object.put(“name", “北川結衣");
object.put(“score", new Integer(200));
object.put(“current", new Double(152.32));
object.put(“nickname", “結衣");
} catch (JSONException e) {
e.printStackTrace();
}
System.out.println(object);
}