Java tutorial
/* * Copyright (c) 2015 SDL, Radagio & R. Oudshoorn * * 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 org.dd4t.providers; import org.apache.commons.codec.binary.Base64; import org.apache.commons.lang3.CharEncoding; import org.dd4t.caching.CacheType; import org.dd4t.core.exceptions.SerializationException; import org.dd4t.core.util.CompressionUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import javax.annotation.Resource; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.UnsupportedEncodingException; /** * Base class for providers defining common utility methods for handling compression and encoding. * * @author R. Kempees */ public abstract class BaseBrokerProvider { private static final Logger LOG = LoggerFactory.getLogger(BaseBrokerProvider.class); private static final Base64 URL_CODER = new Base64(true); // Set these values in Spring configuration protected boolean contentIsCompressed = true; protected boolean contentIsBase64Encoded = true; @Resource protected PayloadCacheProvider cacheProvider; public static String convertStreamToString(InputStream is) throws IOException { /* * To convert the InputStream to String we use the * BufferedReader.readLine() method. We iterate until the BufferedReader * return null which means there's no more data to read. Each line will * appended to a StringBuilder and returned as String. */ if (is != null) { StringBuilder sb = new StringBuilder(); String line; try { BufferedReader reader = new BufferedReader(new InputStreamReader(is, CharEncoding.UTF_8)); while ((line = reader.readLine()) != null) { sb.append(line).append("\n"); } } finally { is.close(); } return sb.toString(); } else { return ""; } } /** * Set the status of content compression * * @param contentIsCompressed String representing a boolean value */ public void setContentIsCompressed(final String contentIsCompressed) { this.contentIsCompressed = Boolean.parseBoolean(contentIsCompressed); } public boolean isContentIsBase64Encoded() { return contentIsBase64Encoded; } public void setContentIsBase64Encoded(boolean contentIsBase64Encoded) { this.contentIsBase64Encoded = contentIsBase64Encoded; } /** * Performs a Base64 decode of the given content String. If property <b>contentIsCompressed</b> is true, it then * decompresses the message using GZip and returns it. Otherwise, it returns a UTF-8 string of the Base64 decoded * string. * * @param content String to decode and decompress * @return String the decoded/decompressed content * @throws SerializationException if the given content cannot be decoded or decompressed */ protected String decodeAndDecompressContent(final String content) throws SerializationException { try { if (!contentIsBase64Encoded) { return content; } LOG.debug("Start decoding."); byte[] decoded = CompressionUtils.decodeBase64(content); if (contentIsCompressed) { LOG.debug("Start decompressing"); return CompressionUtils.decompressGZip(decoded); } LOG.debug("End decoding and decompressing"); return new String(decoded, CharEncoding.UTF_8); } catch (UnsupportedEncodingException uee) { throw new SerializationException("Failed to convert bytes to UTF-8", uee); } } /** * Encodes the given URL parameter to Base64 format * * @param url String representing the message to encode * @return String the Base64 encoded string */ protected String encodeUrl(final String url) { if (url == null) { return ""; } String encoded = null; try { encoded = URL_CODER.encodeAsString(url.getBytes(CharEncoding.UTF_8)); } catch (UnsupportedEncodingException e) { LOG.error(e.getLocalizedMessage(), e); } if (encoded == null) { return ""; } return encoded.trim(); } /** * Builds a key using a named cache type (region) and a URL. This type of key is used to point to * actual payload in the cache. Use this key when looking up objects cached for a particular URL. * * @param type CacheType representing the type (or region) where the associated item is in cache * @param url the path part of the URL of a Tridion item * @return String representing the key pointing to a URL value */ protected String getKey(CacheType type, String url) { return String.format("%s-%s", type, url); } public void setCacheProvider(final PayloadCacheProvider cacheProvider) { this.cacheProvider = cacheProvider; } }