Java tutorial
/* * Copyright (c) 2013. wyouflf (wyouflf@gmail.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 com.dongfang.net.http; import java.io.IOException; import java.io.InterruptedIOException; import java.net.SocketException; import java.net.UnknownHostException; import java.util.HashSet; import javax.net.ssl.SSLHandshakeException; import org.apache.http.NoHttpResponseException; import org.apache.http.client.HttpRequestRetryHandler; import org.apache.http.client.methods.HttpRequestBase; import org.apache.http.impl.client.RequestWrapper; import org.apache.http.protocol.ExecutionContext; import org.apache.http.protocol.HttpContext; import android.os.SystemClock; import com.dongfang.utils.ULog; public class RetryHandler implements HttpRequestRetryHandler { private static final int RETRY_SLEEP_INTERVAL = 500; private static HashSet<Class<?>> exceptionWhiteList = new HashSet<Class<?>>(); private static HashSet<Class<?>> exceptionBlackList = new HashSet<Class<?>>(); static { exceptionWhiteList.add(NoHttpResponseException.class); exceptionWhiteList.add(UnknownHostException.class); exceptionWhiteList.add(SocketException.class); exceptionBlackList.add(InterruptedIOException.class); exceptionBlackList.add(SSLHandshakeException.class); } private final int maxRetries; public RetryHandler(int maxRetries) { this.maxRetries = maxRetries; } @Override public boolean retryRequest(IOException exception, int retriedTimes, HttpContext context) { boolean retry = true; if (exception == null || context == null) { return false; } Boolean b = (Boolean) context.getAttribute(ExecutionContext.HTTP_REQ_SENT); boolean sent = (b != null && b.booleanValue()); if (retriedTimes > maxRetries) { retry = false; } else if (exceptionBlackList.contains(exception.getClass())) { retry = false; } else if (exceptionWhiteList.contains(exception.getClass())) { retry = true; } else if (!sent) { retry = true; } if (retry) { try { Object currRequest = context.getAttribute(ExecutionContext.HTTP_REQUEST); if (currRequest != null) { if (currRequest instanceof HttpRequestBase) { HttpRequestBase requestBase = (HttpRequestBase) currRequest; retry = "GET".equals(requestBase.getMethod()); } else if (currRequest instanceof RequestWrapper) { RequestWrapper requestWrapper = (RequestWrapper) currRequest; retry = "GET".equals(requestWrapper.getMethod()); } } else { retry = false; ULog.e("retry error, curr request is null"); } } catch (Throwable e) { retry = false; ULog.e("retry error", e); } } if (retry) { SystemClock.sleep(RETRY_SLEEP_INTERVAL); // sleep a while and retry http request again. } return retry; } }