AndroidAsyncHttp 臨時修復 JsonHttpResponseHandler 避免死循環

由於 AndroidAsyncHttp 1.4.4 的 JsonHttpResponseHandler 存在死循環的 BUG，1.4.5 版本發布不知道要何時，所以只能臨時替換該類來修復這個錯誤。

Android開源庫loopj的android-async-http的 JsonHttpResponseHandler 存在死循環GC_CONCURRENT

package com.ai9475.extend;

import com.ai9475.meitian.AppManager;
import com.ai9475.meitian.R;
import com.loopj.android.http.JsonHttpResponseHandler;

import android.app.AlertDialog;
import android.content.DialogInterface;
import android.util.Log;

import org.apache.http.Header;
import org.apache.http.HttpStatus;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import org.json.JSONTokener;

import java.io.UnsupportedEncodingException;

/**
 * 復寫 AndroidAsyncHttp 1.4.4 開源庫的 JsonHttpResponseHandler 類
 * 當 1.4.5 released 後失效
 *
 * Created by ZHOUZ on 2014/3/22.
 */
public class ZJsonHttpResponseHandler extends JsonHttpResponseHandler
{
    private static final String LOG_TAG = "JsonHttpResponseHandler";

    /**
     * Returns when request succeeds
     *
     * @param statusCode http response status line
     * @param headers    response headers if any
     * @param response   parsed response if any
     */
    public void onSuccess(int statusCode, Header[] headers, JSONObject response) {

    }

    /**
     * Returns when request succeeds
     *
     * @param statusCode http response status line
     * @param headers    response headers if any
     * @param response   parsed response if any
     */
    public void onSuccess(int statusCode, Header[] headers, JSONArray response) {

    }

    /**
     * Returns when request failed
     *
     * @param statusCode    http response status line
     * @param headers       response headers if any
     * @param throwable     throwable describing the way request failed
     * @param errorResponse parsed response if any
     */
    public void onFailure(int statusCode, Header[] headers, Throwable throwable, JSONObject errorResponse) {

    }

    /**
     * Returns when request failed
     *
     * @param statusCode    http response status line
     * @param headers       response headers if any
     * @param throwable     throwable describing the way request failed
     * @param errorResponse parsed response if any
     */
    public void onFailure(int statusCode, Header[] headers, Throwable throwable, JSONArray errorResponse) {

    }

    @Override
    public void onFailure(int statusCode, Header[] headers, String responseString, Throwable throwable) {
        final AlertDialog.Builder dialog = new AlertDialog.Builder(AppManager.ActivityManager.current());
        dialog.setIcon(android.R.drawable.ic_dialog_info);
        dialog.setTitle(R.string.app_error);
        dialog.setMessage(responseString);
        dialog.setNegativeButton(R.string.sure,
                new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        dialog.dismiss();
                    }
                });
        dialog.show();
    }

    @Override
    public void onSuccess(int statusCode, Header[] headers, String responseString) {

    }

    @Override
    public final void onSuccess(final int statusCode, final Header[] headers, final byte[] responseBytes) {
        if (statusCode != HttpStatus.SC_NO_CONTENT) {
            new Thread(new Runnable() {
                @Override
                public void run() {
                    try {
                        final Object jsonResponse = parseResponse(responseBytes);
                        postRunnable(new Runnable() {
                            @Override
                            public void run() {
                                if (jsonResponse instanceof JSONObject) {
                                    onSuccess(statusCode, headers, (JSONObject) jsonResponse);
                                } else if (jsonResponse instanceof JSONArray) {
                                    onSuccess(statusCode, headers, (JSONArray) jsonResponse);
                                } else if (jsonResponse instanceof String) {
                                    onFailure(statusCode, headers, (String) jsonResponse, new JSONException("Response cannot be parsed as JSON data"));
                                } else {
                                    onFailure(statusCode, headers, new JSONException("Unexpected response type " + jsonResponse.getClass().getName()), (JSONObject) null);
                                }

                            }
                        });
                    } catch (final JSONException ex) {
                        postRunnable(new Runnable() {
                            @Override
                            public void run() {
                                onFailure(statusCode, headers, ex, (JSONObject) null);
                            }
                        });
                    }
                }
            }).start();
        } else {
            onSuccess(statusCode, headers, new JSONObject());
        }
    }

    @Override
    public final void onFailure(final int statusCode, final Header[] headers, final byte[] responseBytes, final Throwable throwable) {
        if (responseBytes != null) {
            new Thread(new Runnable() {
                @Override
                public void run() {
                    try {
                        final Object jsonResponse = parseResponse(responseBytes);
                        postRunnable(new Runnable() {
                            @Override
                            public void run() {
                                if (jsonResponse instanceof JSONObject) {
                                    onFailure(statusCode, headers, throwable, (JSONObject) jsonResponse);
                                } else if (jsonResponse instanceof JSONArray) {
                                    onFailure(statusCode, headers, throwable, (JSONArray) jsonResponse);
                                } else if (jsonResponse instanceof String) {
                                    onFailure(statusCode, headers, (String) jsonResponse, throwable);
                                } else {
                                    onFailure(statusCode, headers, new JSONException("Unexpected response type " + jsonResponse.getClass().getName()), (JSONObject) null);
                                }
                            }
                        });

                    } catch (final JSONException ex) {
                        postRunnable(new Runnable() {
                            @Override
                            public void run() {
                                onFailure(statusCode, headers, ex, (JSONObject) null);
                            }
                        });

                    }
                }
            }).start();
        } else {
            Log.v(LOG_TAG, "response body is null, calling onFailure(Throwable, JSONObject)");
            onFailure(statusCode, headers, throwable, (JSONObject) null);
        }
    }

    /**
     * Returns Object of type {@link JSONObject}, {@link JSONArray}, String, Boolean, Integer, Long,
     * Double or {@link JSONObject#NULL}, see {@link org.json.JSONTokener#nextValue()}
     *
     * @param responseBody response bytes to be assembled in String and parsed as JSON
     * @return Object parsedResponse
     * @throws org.json.JSONException exception if thrown while parsing JSON
     */
    protected Object parseResponse(byte[] responseBody) throws JSONException {
        if (null == responseBody)
            return null;
        Object result = null;
        //trim the string to prevent start with blank, and test if the string is valid JSON, because the parser don't do this :(. If Json is not valid this will return null
        String jsonString = getResponseString(responseBody, getCharset());
        if (jsonString != null) {
            jsonString = jsonString.trim();
            if (jsonString.startsWith("{") || jsonString.startsWith("[")) {
                result = new JSONTokener(jsonString).nextValue();
            }
        }
        if (result == null) {
            result = jsonString;
        }
        return result;
    }

    /**
     * Attempts to encode response bytes as string of set encoding
     *
     * @param charset     charset to create string with
     * @param stringBytes response bytes
     * @return String of set encoding or null
     */
    public static String getResponseString(byte[] stringBytes, String charset) {
        try {
            return stringBytes == null ? null : new String(stringBytes, charset);
        } catch (UnsupportedEncodingException e) {
            Log.e(LOG_TAG, "Encoding response into string failed", e);
            return null;
        }
    }
}

現在如果再出現 HTTP 500 或其他服務端錯誤（輸出非 JSON 字符串）時將會直接彈出服務端頁面內容的對話框方便調試了，現在只能這樣了，等新版本發布後再轉換下吧！