我正在尝试使用 android 应用程序从 yamba 中提取时间线,但是每当我运行该程序时,它都会失败并出现以下错误:
04-15 15:58:18.578: E/AndroidRuntime(5418): FATAL EXCEPTION: Thread-171
04-15 15:58:18.578: E/AndroidRuntime(5418): java.lang.NullPointerException
04-15 15:58:18.578: E/AndroidRuntime(5418): at com.example.yamba.UpdaterService$1.run(UpdaterService.java:32)
代码是这样的:
package com.example.yamba;
import java.util.List;
import winterwell.jtwitter.Twitter;
import winterwell.jtwitter.Twitter.Status;
import winterwell.jtwitter.TwitterException;
import android.app.Service;
import android.content.Intent;
import android.os.IBinder;
import android.util.Log;
public class UpdaterService extends Service{
static final String TAG = "UpdaterService";
static final int DELAY = 30; //seconden
Twitter twitter;
@Override
public void onCreate() {
super.onCreate();
Twitter twitter = new Twitter("student", "password");
twitter.setAPIRootUrl("http://yamba.marakana.com/api");
Log.d(TAG, "onCreated");
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
new Thread() {
public void run() {
try {
while(true) {
List<Status> timeline = twitter.getPublicTimeline();
for (Status status : timeline) {
Log.d(TAG, String.format("%s: %s", status.user.name,
status.text));
}
Thread.sleep(DELAY*1000);
}
} catch (TwitterException e) {
Log.e(TAG, "Failed because of network error.", e);
} catch (InterruptedException e) {
Log.d(TAG, "Updater interrupted", e);
}
}
}.start();
Log.d(TAG, "onStarted");
return super.onStartCommand(intent, flags, startId);
}
@Override
public void onDestroy() {
super.onDestroy();
Log.d(TAG, "onDestroyed");
}
@Override
public IBinder onBind(Intent intent) {
return null;
}
}
第 32 行是:List<Status> timeline = twitter.getPublicTimeline();