org.cancergrid.ws.util.HttpContentReader.java Source code

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Here is the source code for org.cancergrid.ws.util.HttpContentReader.java

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/*L
 * Copyright Oracle Inc
 *
 * Distributed under the OSI-approved BSD 3-Clause License.
 * See http://ncip.github.com/cadsr-cgmdr/LICENSE.txt for details.
 */

/**
 * Copyright (c) 2005-2008 CancerGrid Consortium <http://www.cancergrid.org/>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in the
 * Software without restriction, including without limitation the rights to use, copy,
 * modify, merge, publish, distribute, sublicense, and/or sell copies of the Software,
 * and to permit persons to whom the Software is furnished to do so, subject to the
 * following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all copies
 * or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
 * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
 * PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
 * FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */

package org.cancergrid.ws.util;

import java.io.IOException;

import org.apache.commons.httpclient.DefaultHttpMethodRetryHandler;
import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.HttpException;
import org.apache.commons.httpclient.HttpMethod;
import org.apache.commons.httpclient.HttpStatus;
import org.apache.commons.httpclient.methods.GetMethod;
import org.apache.commons.httpclient.methods.PostMethod;
import org.apache.commons.httpclient.methods.RequestEntity;
import org.apache.commons.httpclient.methods.StringRequestEntity;
import org.apache.commons.httpclient.params.HttpMethodParams;
import org.apache.commons.httpclient.protocol.Protocol;
import org.apache.log4j.Logger;

/**
 * Utility for reading HTML content from a given URL. Uses Apache HttpClient.
 *
 * @author <a href="mailto:Andrew.Tsui@comlab.ox.ac.uk">Andrew Tsui</a> (<a
 *         href="http://www.cancergrid.org">CancerGrid Consortium</a>)
 * @version 1.0
 */
public class HttpContentReader {
    /**
     * Log4J Logger
     */
    private static Logger LOG = Logger.getLogger(HttpContentReader.class);

    public static String getHttpContent(String httpUrl) {
        if (httpUrl.contains("&amp;")) {
            httpUrl = httpUrl.replace("&amp;", "&");
        }
        if (httpUrl.contains("?")) {
            return getHttpContent(httpUrl.substring(0, httpUrl.indexOf("?")),
                    httpUrl.substring(httpUrl.indexOf("?") + 1), Method.GET);
        } else {
            return getHttpContent(httpUrl, null, Method.GET);
        }
    }

    public static String getHttpContent(String httpUrl, String query, Method method) {
        LOG.debug("getHttpContent(httpUrl): " + httpUrl);
        LOG.debug("getHttpContent(query): " + query);
        LOG.debug("getHttpContent(method): " + method);

        HttpMethod httpMethod = null;
        if (httpUrl.contains("&amp;")) {
            httpUrl = httpUrl.replace("&amp;", "&");
        }

        if (query != null && query.length() > 0 && query.startsWith("?") && query.contains("&amp;")) {
            query = query.replace("&amp;", "&");
        }

        try {
            //LOG.debug("Querying: " + httpUrl);
            if (method == Method.GET) {
                httpMethod = new GetMethod(httpUrl);
                if (query != null && query.length() > 0) {
                    httpMethod.setQueryString(query);
                }
            } else if (method == Method.POST) {
                httpMethod = new PostMethod(httpUrl);
                if (query != null && query.length() > 0) {
                    RequestEntity entity = new StringRequestEntity(query, "text/xml", "UTF-8");
                    ((PostMethod) httpMethod).setRequestEntity(entity);
                }
            }

            httpMethod.setFollowRedirects(true);

            httpMethod.getParams().setParameter(HttpMethodParams.RETRY_HANDLER,
                    new DefaultHttpMethodRetryHandler(3, false));

            Protocol.registerProtocol("https", new Protocol("https",
                    new org.apache.commons.httpclient.contrib.ssl.EasySSLProtocolSocketFactory(), 443));
            HttpClient client = new HttpClient();
            int statusCode = client.executeMethod(httpMethod);
            if (statusCode != HttpStatus.SC_OK) {
                LOG.error("Method failed: " + httpMethod.getStatusLine());
                LOG.error("Error querying: " + httpMethod.getURI().toString());
                throw new Exception("Method failed: " + httpMethod.getStatusLine());
            }

            byte[] responseBody = httpMethod.getResponseBody();
            return new String(responseBody, "UTF-8");
        } catch (HttpException e) {
            LOG.error("Fatal protocol violation: " + e.getMessage());
        } catch (IOException e) {
            LOG.error("Fatal transport error: " + e.getMessage());
        } catch (Exception e) {
            LOG.error(e.getMessage());
        } finally {
            httpMethod.releaseConnection();
        }
        return null;
    }

    public static enum Method {
        GET, POST
    };
}