net.tsz.afinal.http.AjaxRequestHandler.java Source code

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Here is the source code for net.tsz.afinal.http.AjaxRequestHandler.java

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/**
 * Copyright (c) 2012-2013, Michael Yang ?? (www.yangfuhai.com).
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package net.tsz.afinal.http;

import java.io.IOException;
import java.net.ConnectException;
import java.net.UnknownHostException;

import net.tsz.afinal.common.AsyncTask;
import net.tsz.afinal.http.entityhandler.EntityCallBack;
import net.tsz.afinal.http.entityhandler.FileEntityHandler;
import net.tsz.afinal.http.entityhandler.StringEntityHandler;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.StatusLine;
import org.apache.http.client.HttpRequestRetryHandler;
import org.apache.http.client.HttpResponseException;
import org.apache.http.client.methods.HttpUriRequest;
import org.apache.http.impl.client.AbstractHttpClient;
import org.apache.http.protocol.HttpContext;

import android.os.SystemClock;

public class AjaxRequestHandler extends AsyncTask<Object, Object, Object> {

    private final AbstractHttpClient client;
    private final HttpContext context;

    private final static StringEntityHandler mStrEntityHandler = new StringEntityHandler();
    private final static FileEntityHandler mFileEntityHandler = new FileEntityHandler();

    @SuppressWarnings("rawtypes")
    private final AjaxCallBack callback;

    private int executionCount = 0;
    private String targetUrl = null;
    private String charset;

    public AjaxRequestHandler(AbstractHttpClient client, HttpContext context, AjaxCallBack<?> callback,
            String charset) {
        this.client = client;
        this.context = context;
        this.callback = callback;
        this.charset = charset;
    }

    private void makeRequestWithRetries(HttpUriRequest request) throws ConnectException {

        boolean retry = true;
        IOException cause = null;
        HttpRequestRetryHandler retryHandler = client.getHttpRequestRetryHandler();
        while (retry) {
            try {
                if (!isCancelled()) {
                    HttpResponse response = client.execute(request, context);
                    if (!isCancelled()) {
                        handleResponse(response);
                    }
                }
                return;
            } catch (UnknownHostException e) {
                publishProgress(Update_failure, e, "can't resolve host");
                return;
            } catch (IOException e) {
                cause = e;
                retry = retryHandler.retryRequest(cause, ++executionCount, context);
            } catch (NullPointerException e) {
                // HttpClient 4.0.x ?bug
                // http://code.google.com/p/android/issues/detail?id=5255
                cause = new IOException("NPE in HttpClient" + e.getMessage());
                retry = retryHandler.retryRequest(cause, ++executionCount, context);
            }
        }

        //??
        ConnectException ex = new ConnectException();
        ex.initCause(cause);
        throw ex;
    }

    @Override
    protected Object doInBackground(Object... params) {
        if (params != null && params.length == 2)
            targetUrl = String.valueOf(params[1]);

        try {
            publishProgress(Update_start); // 

            makeRequestWithRetries((HttpUriRequest) params[0]);

            publishProgress(Update_failure, null, null); // ?
        } catch (IOException e) {
            publishProgress(Update_failure, e, null); // ?
        }

        return null;
    }

    private final static int Update_start = 1;
    private final static int Update_loading = 2;
    private final static int Update_failure = 3;
    private final static int Update_success = 4;

    @SuppressWarnings("unchecked")
    @Override
    protected void onProgressUpdate(Object... values) {
        int update = Integer.valueOf(String.valueOf(values[0]));
        switch (update) {
        case Update_start:
            if (callback != null)
                callback.onStart();
            break;
        case Update_loading:
            if (callback != null)
                callback.onLoading(Long.valueOf(String.valueOf(values[1])),
                        Long.valueOf(String.valueOf(values[2])));
            break;
        case Update_failure:
            if (callback != null)
                callback.onFailure((Throwable) values[1], (String) values[2]);
            break;
        case Update_success:
            if (callback != null)
                callback.onSuccess(values[1]);
            break;
        default:
            break;
        }
        super.onProgressUpdate(values);
    }

    private void handleResponse(HttpResponse response) {
        StatusLine status = response.getStatusLine();
        if (status.getStatusCode() >= 300) {
            publishProgress(Update_failure,
                    new HttpResponseException(status.getStatusCode(), status.getReasonPhrase()),
                    "response status code:" + status.getStatusCode());
        } else {
            try {
                HttpEntity temp = response.getEntity();
                Object responseBody = null;
                if (temp != null) {
                    if (targetUrl != null)
                        responseBody = mFileEntityHandler.handleEntity(temp, new EntityCallBackImpl(), targetUrl);
                    else
                        responseBody = mStrEntityHandler.handleEntity(temp, new EntityCallBackImpl(), charset);
                }
                publishProgress(Update_success, responseBody);

            } catch (IOException e) {
                publishProgress(Update_failure, e, (String) null);
            }

        }
    }

    class EntityCallBackImpl implements EntityCallBack {
        private long time;

        public EntityCallBackImpl() {
            time = SystemClock.uptimeMillis();
        }

        @Override
        public void callBack(long count, long current) {
            if (callback != null && callback.isProgress()) {
                long thisTime = SystemClock.uptimeMillis();
                if (thisTime - time > callback.getRate()) {
                    time = thisTime;
                    publishProgress(Update_loading, count, current);
                }
            }
        }

    }

}