目标主机不能为空错误

Question

我在使用Android从网址获取JSON时出现问题，并且我的网址中的标题中包含错误。我在下面发布了相关代码。如果需要更多，我可以提供。目前，我提供了由错误标记的代码片段。

错误：

    04-06 23:13:44.533  20566-20855/edu.appdesign.leaguestats E/AndroidRuntime﹕ FATAL EXCEPTION: AsyncTask #1
    Process: edu.appdesign.leaguestats, PID: 20566
    java.lang.RuntimeException: An error occured while executing doInBackground()
            at android.os.AsyncTask$3.done(AsyncTask.java)
            at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
            at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
            at java.util.concurrent.FutureTask.run(FutureTask.java:242)
            at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
            at java.lang.Thread.run(Thread.java:864)
     Caused by: java.lang.IllegalArgumentException: Illegal character in query at index 166: https://prod.api.pvp.net/api/lol/NA/v1.4/summoner/by-name/android.widget.EditText%7B41b76038+VFED..CL+.F......+0%2C0-804%2C118+%237f08003d+app%3Aid%2Fname%7D?api_key=<d96236d2-6ee3-4cfd-afa7-f41bdbc11128>
            at java.net.URI.create(URI.java:727)
            at org.apache.http.client.methods.HttpPost.<init>(HttpPost.java)
            at edu.appdesign.leaguestats.JSONParser.getJSONFromUrl(JSONParser.java:45)
            at edu.appdesign.leaguestats.StatsActivity$GetStats.doInBackground(StatsActivity.java:63)
            at edu.appdesign.leaguestats.StatsActivity$GetStats.doInBackground(StatsActivity.java:24)
            at android.os.AsyncTask$2.call(AsyncTask.java)
            at java.util.concurrent.FutureTask.run(FutureTask.java:237)
            at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
            at java.lang.Thread.run(Thread.java:864)
04-06 23:13:44.543  19569-20025/? E/ActivityManager﹕ App crashed! Process: edu.appdesign.leaguestats

公共类StatsActivity扩展了Activity {

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.stats_activity);

    GetStats stats = new GetStats();
    stats.execute();
}

class GetStats extends AsyncTask<Void, Void, Void> {

    private String api_key="d96236d2-6ee3-4cfd-afa7-f41bdbc11128";
    String region = MainActivity.region;
    String name = MainActivity.name;
    String url = null;
    String encodedName = null;
    String encodedKey = null;
    String encodedRegion = null;
    TextView textId = (TextView) findViewById(R.id.id);
    TextView textName = (TextView) findViewById(R.id.name);
    TextView textProfileIconId = (TextView) findViewById(R.id.profileIconId);
    TextView textRevisionDate = (TextView) findViewById(R.id.revisionDate);
    TextView textSummonerLevel = (TextView) findViewById(R.id.summonerLevel);

    long jId;
    String jName;
    int jProfileIconId;
    long jRevisionDate;
    long jSummonerLevel;

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        try {
            encodedName = URLEncoder.encode(name, "UTF-8");
            encodedKey = URLEncoder.encode(api_key, "UTF-8");
            encodedRegion = URLEncoder.encode(region, "UTF-8");
            url = "https://prod.api.pvp.net/api/lol/" + encodedRegion + "/v1.4/summoner/by-name/" + encodedName + "?api_key=<" + encodedKey + ">";

        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }

    }

    @Override
    protected Void doInBackground(Void... arg0) {
        JSONParser jParser = new JSONParser();
        JSONObject json = jParser.getJSONFromUrl(url);

        try {

            jId = json.getLong("id");
            jName = json.getString("dataVersion");
            jProfileIconId = json.getInt("profileIconId");
            jRevisionDate = json.getLong("revisionDate");
            jSummonerLevel = json.getLong("summonerLevel");

        } catch (JSONException e) {
            e.printStackTrace();
        }

        return null;
    }

    @Override
    protected void onPostExecute(Void result) {
        super.onPostExecute(result);
        /**
         * Put json data on screen
         * */

        String id = String.valueOf(jId);
        String name = String.valueOf(jName);
        String icon = String.valueOf(jProfileIconId);
        String rev = String.valueOf(jRevisionDate);
        String summLevel = String.valueOf(jSummonerLevel);

        textId.setText(id);
        textName.setText(name);
        textProfileIconId.setText(icon);
        textRevisionDate.setText(rev);
        textSummonerLevel.setText(summLevel);

        }
    }
}