| /* |
| * Copyright 2013 Google Inc. |
| * |
| * 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.google.gwt.user.server.rpc; |
| |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.net.HttpURLConnection; |
| import java.net.MalformedURLException; |
| import java.net.URL; |
| import java.net.URLConnection; |
| import java.text.ParseException; |
| import java.util.ArrayList; |
| import java.util.List; |
| |
| /** |
| * A simple and relatively naive client for downloading serialization policies from a URL. |
| * (Intended only for development.) |
| */ |
| class SerializationPolicyClient { |
| private final int connectTimeout; |
| private final int readTimeout; |
| |
| /** |
| * Creates an client with the given configuration, |
| * @param connectTimeoutMs see {@link URLConnection#setConnectTimeout} |
| * @param readTimeoutMs see {@link URLConnection#setReadTimeout} |
| */ |
| SerializationPolicyClient(int connectTimeoutMs, int readTimeoutMs) { |
| this.connectTimeout = connectTimeoutMs; |
| this.readTimeout = readTimeoutMs; |
| } |
| |
| SerializationPolicy loadPolicy(String url, Logger logger) { |
| URL urlObj; |
| try { |
| urlObj = new URL(url); |
| } catch (MalformedURLException e) { |
| logger.logError("Can't parse serialization policy URL: " + url, e); |
| return null; |
| } |
| |
| URLConnection conn; |
| InputStream in; |
| try { |
| conn = urlObj.openConnection(); |
| conn.setConnectTimeout(connectTimeout); |
| conn.setReadTimeout(readTimeout); |
| // The code server doesn't redirect. Fail fast if we get a redirect since |
| // it's likely a configuration error. |
| if (conn instanceof HttpURLConnection) { |
| ((HttpURLConnection)conn).setInstanceFollowRedirects(false); |
| } |
| conn.connect(); |
| in = conn.getInputStream(); |
| } catch (IOException e) { |
| logger.logError("Can't open serialization policy URL: " + url, e); |
| return null; |
| } |
| |
| return readPolicy(in, url, logger); |
| } |
| |
| /** |
| * Attempts to read a policy from a given InputStream and logs any errors. |
| * |
| * @param sourceName names the source of the input stream for log messages. |
| * @return the policy or null if unavailable. |
| */ |
| private static SerializationPolicy readPolicy(InputStream in, String sourceName, |
| Logger logger) { |
| try { |
| List<ClassNotFoundException> errs = new ArrayList<ClassNotFoundException>(); |
| SerializationPolicy policy = SerializationPolicyLoader.loadFromStream(in, errs); |
| logger.logInfo("Downloaded serialization policy from " + sourceName); |
| |
| if (!errs.isEmpty()) { |
| logMissingClasses(logger, errs); |
| } |
| return policy; |
| |
| } catch (ParseException e) { |
| logger.logError("Can't parse serialization policy from " + sourceName, e); |
| return null; |
| } catch (IOException e) { |
| logger.logError("Can't read serialization policy from " + sourceName, e); |
| return null; |
| } finally { |
| try { |
| in.close(); |
| } catch (IOException e) { |
| logger.logError("Can't close serialization policy url: " + sourceName, e); |
| } |
| } |
| } |
| |
| private static void logMissingClasses(Logger logger, List<ClassNotFoundException> errs) { |
| StringBuilder message = new StringBuilder(); |
| message.append("Unable to load server-side classes used by policy:\n"); |
| |
| int limit = Math.min(10, errs.size()); |
| for (int i = 0; i < limit; i++) { |
| message.append(" " + errs.get(i).getMessage() + "\n"); |
| } |
| int omitted = errs.size() - limit; |
| if (omitted > 0) { |
| message.append(" (omitted " + omitted + " more classes)\n"); |
| } |
| logger.logInfo(message.toString()); |
| } |
| |
| /** |
| * Destination for the loader's log messages. |
| */ |
| interface Logger { |
| void logInfo(String message); |
| void logError(String message, Throwable throwable); |
| } |
| } |