1d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen/** 2d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * Copyright 2013 Florian Schmaus 3d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * 4d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * All rights reserved. Licensed under the Apache License, Version 2.0 (the "License"); 5d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * you may not use this file except in compliance with the License. 6d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * You may obtain a copy of the License at 7d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * 8d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * http://www.apache.org/licenses/LICENSE-2.0 9d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * 10d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * Unless required by applicable law or agreed to in writing, software 11d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * distributed under the License is distributed on an "AS IS" BASIS, 12d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * See the License for the specific language governing permissions and 14d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * limitations under the License. 15d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen */ 16d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chenpackage org.jivesoftware.smack.compression; 17d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen 18d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chenimport java.io.IOException; 19d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chenimport java.io.InputStream; 20d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chenimport java.io.OutputStream; 21d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chenimport java.lang.reflect.InvocationTargetException; 22d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chenimport java.lang.reflect.Method; 23d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chenimport java.util.zip.Deflater; 24d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chenimport java.util.zip.DeflaterOutputStream; 25d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chenimport java.util.zip.Inflater; 26d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chenimport java.util.zip.InflaterInputStream; 27d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen 28d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen/** 29d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * This class provides XMPP "zlib" compression with the help of the Deflater class of the Java API. Note that the method 30d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * needed is available since Java7, so it will only work with Java7 or higher (hence it's name). 31d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * 32d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * @author Florian Schmaus 33d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * @see <a 34d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * href="http://docs.oracle.com/javase/7/docs/api/java/util/zip/Deflater.html#deflate(byte[], int, int, int)">The 35d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * required deflate() method</a> 36d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * 37d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen */ 38d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chenpublic class Java7ZlibInputOutputStream extends XMPPInputOutputStream { 39d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen private final static Method method; 40d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen private final static boolean supported; 41d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen private final static int compressionLevel = Deflater.DEFAULT_STRATEGY; 42d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen 43d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen static { 44d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen Method m = null; 45d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen try { 46d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen m = Deflater.class.getMethod("deflate", byte[].class, int.class, int.class, int.class); 47d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen } catch (SecurityException e) { 48d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen } catch (NoSuchMethodException e) { 49d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen } 50d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen method = m; 51d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen supported = (method != null); 52d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen } 53d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen 54d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen public Java7ZlibInputOutputStream() { 55d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen compressionMethod = "zlib"; 56d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen } 57d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen 58d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen @Override 59d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen public boolean isSupported() { 60d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen return supported; 61d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen } 62d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen 63d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen @Override 64d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen public InputStream getInputStream(InputStream inputStream) { 65d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen return new InflaterInputStream(inputStream, new Inflater(), 512) { 66d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen /** 67d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * Provide a more InputStream compatible version. A return value of 1 means that it is likely to read one 68d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * byte without blocking, 0 means that the system is known to block for more input. 69d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * 70d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * @return 0 if no data is available, 1 otherwise 71d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * @throws IOException 72d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen */ 73d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen @Override 74d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen public int available() throws IOException { 75d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen /* 76d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * aSmack related remark (where KXmlParser is used): 77d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * This is one of the funny code blocks. InflaterInputStream.available violates the contract of 78d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * InputStream.available, which breaks kXML2. 79d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * 80d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * I'm not sure who's to blame, oracle/sun for a broken api or the google guys for mixing a sun bug with 81d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * a xml reader that can't handle it.... 82d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * 83d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen * Anyway, this simple if breaks suns distorted reality, but helps to use the api as intended. 84d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen */ 85d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen if (inf.needsInput()) { 86d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen return 0; 87d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen } 88d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen return super.available(); 89d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen } 90d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen }; 91d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen } 92d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen 93d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen @Override 94d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen public OutputStream getOutputStream(OutputStream outputStream) { 95d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen return new DeflaterOutputStream(outputStream, new Deflater(compressionLevel)) { 96d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen public void flush() throws IOException { 97d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen if (!supported) { 98d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen super.flush(); 99d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen return; 100d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen } 101d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen int count = 0; 102d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen if (!def.needsInput()) { 103d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen do { 104d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen count = def.deflate(buf, 0, buf.length); 105d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen out.write(buf, 0, count); 106d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen } while (count > 0); 107d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen out.flush(); 108d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen } 109d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen try { 110d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen do { 111d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen count = (Integer) method.invoke(def, buf, 0, buf.length, 2); 112d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen out.write(buf, 0, count); 113d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen } while (count > 0); 114d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen } catch (IllegalArgumentException e) { 115d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen throw new IOException("Can't flush"); 116d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen } catch (IllegalAccessException e) { 117d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen throw new IOException("Can't flush"); 118d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen } catch (InvocationTargetException e) { 119d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen throw new IOException("Can't flush"); 120d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen } 121d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen super.flush(); 122d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen } 123d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen }; 124d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen } 125d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen 126d7955ce24d294fb2014c59d11fca184471056f44Shuyi Chen} 127