Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. The ASF licenses this file to You * 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. For additional information regarding * copyright in this work, please see the NOTICE file in the top level * directory of this distribution. */ package org.apache.roller.weblogger.util; import java.net.HttpURLConnection; import java.net.MalformedURLException; import java.net.URL; import javax.mail.internet.ContentType; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.roller.weblogger.business.WebloggerFactory; import org.apache.roller.weblogger.business.WeblogEntryManager; /** * Utility for deailing with mediacast files. */ public final class MediacastUtil { private static final Log log = LogFactory.getLog(MediacastUtil.class); public static final int BAD_URL = 1; public static final int CHECK_FAILED = 2; public static final int BAD_RESPONSE = 3; public static final int INCOMPLETE = 4; // non-instantiable private MediacastUtil() { } /** * Validate a Mediacast resource. */ public static final MediacastResource lookupResource(String url) throws MediacastException { if (url == null || url.trim().length() == 0) { return null; } MediacastResource resource = null; try { HttpURLConnection con = (HttpURLConnection) new URL(url).openConnection(); con.setRequestMethod("HEAD"); int response = con.getResponseCode(); String message = con.getResponseMessage(); if (response != 200) { log.debug("Mediacast error " + response + ":" + message + " from url " + url); throw new MediacastException(BAD_RESPONSE, "weblogEdit.mediaCastResponseError"); } else { String contentType = con.getContentType(); long length = con.getContentLength(); if (contentType == null || length == -1) { log.debug("Response valid, but contentType or length is invalid"); throw new MediacastException(INCOMPLETE, "weblogEdit.mediaCastLacksContentTypeOrLength"); } resource = new MediacastResource(url, contentType, length); log.debug("Valid mediacast resource = " + resource.toString()); } } catch (MalformedURLException mfue) { log.debug("Malformed MediaCast url: " + url); throw new MediacastException(BAD_URL, "weblogEdit.mediaCastUrlMalformed", mfue); } catch (Exception e) { log.error("ERROR while checking MediaCast URL: " + url + ": " + e.getMessage()); throw new MediacastException(CHECK_FAILED, "weblogEdit.mediaCastFailedFetchingInfo", e); } return resource; } }