SMACK-389 Plugable compression framework

This commit adds the ability to plug-in different compression handlers
for different compression methods. It is also possible to add more
then one handler for the same method. The order how the handlers are
added determines which handler is tried first for usage. This is used
for the 'zlib' compression method, which now can be either provided by
Java7 or by JZlib (just like it was done before).

git-svn-id: http://svn.igniterealtime.org/svn/repos/smack/trunk@13522 b35dd754-fafc-0310-a699-88a17e54d16e

build/eclipse/classpath

@@ -11,7 +11,6 @@
 	<classpathentry kind="lib" path="build/build/xmlunit.jar"/>
 	<classpathentry kind="lib" path="build/javassist-3.10.0.GA.jar"/>
 	<classpathentry kind="lib" path="build/jaxen.jar"/>
-	<classpathentry kind="lib" path="build/merge/jzlib.jar"/>
 	<classpathentry kind="lib" path="build/merge/xpp.jar" sourcepath="/gtalksms/lib/xpp3-1.1.4c_src.zip"/>
 	<classpathentry kind="lib" path="build/mockito-all-1.8.2.jar"/>
 	<classpathentry kind="lib" path="build/objenesis-1.1.jar"/>
@@ -28,5 +27,6 @@
 	<classpathentry kind="lib" path="jingle/extension/build/merge/jstun.jar"/>
 	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
 	<classpathentry kind="lib" path="build/junit-4.10.jar"/>
+	<classpathentry kind="lib" path="build/merge/jzlib.jar"/>
 	<classpathentry kind="output" path="target/classes"/>
 </classpath>

source/org/jivesoftware/smack/Connection.java

@@ -23,8 +23,10 @@ package org.jivesoftware.smack;
 import java.io.Reader;
 import java.io.Writer;
 import java.lang.reflect.Constructor;
+import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
+import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
@@ -33,6 +35,9 @@ import java.util.concurrent.CopyOnWriteArrayList;
 import java.util.concurrent.CopyOnWriteArraySet;
 import java.util.concurrent.atomic.AtomicInteger;
 
+import org.jivesoftware.smack.compression.JzlibInputOutputStream;
+import org.jivesoftware.smack.compression.XMPPInputOutputStream;
+import org.jivesoftware.smack.compression.Java7ZlibInputOutputStream;
 import org.jivesoftware.smack.debugger.SmackDebugger;
 import org.jivesoftware.smack.filter.PacketFilter;
 import org.jivesoftware.smack.packet.Packet;
@@ -90,6 +95,8 @@ public abstract class Connection {
     private final static Set<ConnectionCreationListener> connectionEstablishedListeners =
             new CopyOnWriteArraySet<ConnectionCreationListener>();
 
+    protected final static List<XMPPInputOutputStream> compressionHandlers = new ArrayList<XMPPInputOutputStream>(2);
+
     /**
      * Value that indicates whether debugging is enabled. When enabled, a debug
      * window will apear for each new connection that will contain the following
@@ -116,6 +123,10 @@ public abstract class Connection {
         }
         // Ensure the SmackConfiguration class is loaded by calling a method in it.
         SmackConfiguration.getVersion();
+        // Add the Java7 compression handler first, since it's preferred
+        compressionHandlers.add(new Java7ZlibInputOutputStream());
+        // If we don't have access to the Java7 API use the JZlib compression handler
+        compressionHandlers.add(new JzlibInputOutputStream());
     }
 
     /**
@@ -193,6 +204,8 @@ public abstract class Connection {
      */
     protected final ConnectionConfiguration config;
 
+    protected XMPPInputOutputStream compressionHandler;
+
     /**
      * Create a new Connection to a XMPP server.
      * 

source/org/jivesoftware/smack/XMPPConnection.java

@@ -20,6 +20,7 @@
 
 package org.jivesoftware.smack;
 
+import org.jivesoftware.smack.compression.XMPPInputOutputStream;
 import org.jivesoftware.smack.filter.PacketFilter;
 import org.jivesoftware.smack.packet.Packet;
 import org.jivesoftware.smack.packet.Presence;
@@ -33,9 +34,17 @@ import javax.net.ssl.SSLSocket;
 import javax.security.auth.callback.Callback;
 import javax.security.auth.callback.CallbackHandler;
 import javax.security.auth.callback.PasswordCallback;
-import java.io.*;
+
+import java.io.BufferedReader;
+import java.io.BufferedWriter;
+import java.io.ByteArrayInputStream;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.OutputStream;
+import java.io.OutputStreamWriter;
 import java.lang.reflect.Constructor;
-import java.lang.reflect.Method;
 import java.net.Socket;
 import java.net.UnknownHostException;
 import java.security.KeyStore;
@@ -85,10 +94,11 @@ public class XMPPConnection extends Connection {
      * Collection of available stream compression methods offered by the server.
      */
     private Collection<String> compressionMethods;
+
     /**
-     * Flag that indicates if stream compression is actually in use.
+     * Set to true by packet writer if the server acknowledged the compression
      */
-    private boolean usingCompression;
+    private boolean serverAckdCompression = false;
 
 
     /**
@@ -571,7 +581,8 @@ public class XMPPConnection extends Connection {
     private void initConnection() throws XMPPException {
         boolean isFirstInitialization = packetReader == null || packetWriter == null;
         if (!isFirstInitialization) {
-            usingCompression = false;
+            compressionHandler = null;
+            serverAckdCompression = false;
         }
 
         // Set the reader and writer instance variables
@@ -669,7 +680,7 @@ public class XMPPConnection extends Connection {
 
     private void initReaderAndWriter() throws XMPPException {
         try {
-            if (!usingCompression) {
+            if (compressionHandler == null) {
                 reader =
                         new BufferedReader(new InputStreamReader(socket.getInputStream(), "UTF-8"));
                 writer = new BufferedWriter(
@@ -677,24 +688,15 @@ public class XMPPConnection extends Connection {
             }
             else {
                 try {
-                    Class<?> zoClass = Class.forName("com.jcraft.jzlib.ZOutputStream");
+                    OutputStream os = compressionHandler.getOutputStream(socket.getOutputStream());
-                    Constructor<?> constructor =
+                    writer = new BufferedWriter(new OutputStreamWriter(os, "UTF-8"));
-                            zoClass.getConstructor(OutputStream.class, Integer.TYPE);
-                    Object out = constructor.newInstance(socket.getOutputStream(), 9);
-                    Method method = zoClass.getMethod("setFlushMode", Integer.TYPE);
-                    method.invoke(out, 2);
-                    writer =
-                            new BufferedWriter(new OutputStreamWriter((OutputStream) out, "UTF-8"));
 
-                    Class<?> ziClass = Class.forName("com.jcraft.jzlib.ZInputStream");
+                    InputStream is = compressionHandler.getInputStream(socket.getInputStream());
-                    constructor = ziClass.getConstructor(InputStream.class);
+                    reader = new BufferedReader(new InputStreamReader(is, "UTF-8"));
-                    Object in = constructor.newInstance(socket.getInputStream());
-                    method = ziClass.getMethod("setFlushMode", Integer.TYPE);
-                    method.invoke(in, 2);
-                    reader = new BufferedReader(new InputStreamReader((InputStream) in, "UTF-8"));
                 }
                 catch (Exception e) {
                     e.printStackTrace();
+                    compressionHandler = null;
                     reader = new BufferedReader(
                             new InputStreamReader(socket.getInputStream(), "UTF-8"));
                     writer = new BufferedWriter(
@@ -869,17 +871,27 @@ public class XMPPConnection extends Connection {
     }
 
     /**
-     * Returns true if the specified compression method was offered by the server.
+     * Returns the compression handler that can be used for one compression methods offered by the server.
+     * 
+     * @return a instance of XMPPInputOutputStream or null if no suitable instance was found
      * 
-     * @param method the method to check.
-     * @return true if the specified compression method was offered by the server.
      */
-    private boolean hasAvailableCompressionMethod(String method) {
+    private XMPPInputOutputStream maybeGetCompressionHandler() {
-        return compressionMethods != null && compressionMethods.contains(method);
+        if (compressionMethods != null) {
+            for (XMPPInputOutputStream handler : compressionHandlers) {
+                if (!handler.isSupported())
+                    continue;
+
+                String method = handler.getCompressionMethod();
+                if (compressionMethods.contains(method))
+                    return handler;
+            }
+        }
+        return null;
     }
 
     public boolean isUsingCompression() {
-        return usingCompression;
+        return compressionHandler != null && serverAckdCompression;
     }
 
     /**
@@ -902,14 +914,9 @@ public class XMPPConnection extends Connection {
         if (authenticated) {
             throw new IllegalStateException("Compression should be negotiated before authentication.");
         }
-        try {
+
-            Class.forName("com.jcraft.jzlib.ZOutputStream");
+        if ((compressionHandler = maybeGetCompressionHandler()) != null) {
-        }
+            requestStreamCompression(compressionHandler.getCompressionMethod());
-        catch (ClassNotFoundException e) {
-            throw new IllegalStateException("Cannot use compression. Add smackx.jar to the classpath");
-        }
-        if (hasAvailableCompressionMethod("zlib")) {
-            requestStreamCompression();
             // Wait until compression is being used or a timeout happened
             synchronized (this) {
                 try {
@@ -919,7 +926,7 @@ public class XMPPConnection extends Connection {
                     // Ignore.
                 }
             }
-            return usingCompression;
+            return isUsingCompression();
         }
         return false;
     }
@@ -929,10 +936,10 @@ public class XMPPConnection extends Connection {
      * then negotiation of stream compression can only happen after TLS was negotiated. If TLS
      * compression is being used the stream compression should not be used.
      */
-    private void requestStreamCompression() {
+    private void requestStreamCompression(String method) {
         try {
             writer.write("<compress xmlns='http://jabber.org/protocol/compress'>");
-            writer.write("<method>zlib</method></compress>");
+            writer.write("<method>" + method + "</method></compress>");
             writer.flush();
         }
         catch (IOException e) {
@@ -946,8 +953,7 @@ public class XMPPConnection extends Connection {
      * @throws Exception if there is an exception starting stream compression.
      */
     void startStreamCompression() throws Exception {
-        // Secure the plain connection
+        serverAckdCompression = true;
-        usingCompression = true;
         // Initialize the reader and writer with the new secured version
         initReaderAndWriter();
 
@@ -986,7 +992,7 @@ public class XMPPConnection extends Connection {
      *      appropiate error messages to end-users.
      */
     public void connect() throws XMPPException {
-        // Stablishes the connection, readers and writers
+        // Establishes the connection, readers and writers
         connectUsingConfiguration(config);
         // Automatically makes the login if the user was previouslly connected successfully
         // to the server and the connection was terminated abruptly

source/org/jivesoftware/smack/compression/Java7ZlibInputOutputStream.java

@@ -0,0 +1,126 @@
+/**
+ * Copyright 2013 Florian Schmaus
+ *
+ * All rights reserved. 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.jivesoftware.smack.compression;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.util.zip.Deflater;
+import java.util.zip.DeflaterOutputStream;
+import java.util.zip.Inflater;
+import java.util.zip.InflaterInputStream;
+
+/**
+ * This class provides XMPP "zlib" compression with the help of the Deflater class of the Java API. Note that the method
+ * needed is available since Java7, so it will only work with Java7 or higher (hence it's name).
+ * 
+ * @author Florian Schmaus
+ * @see <a
+ * href="http://docs.oracle.com/javase/7/docs/api/java/util/zip/Deflater.html#deflate(byte[], int, int, int)">The
+ * required deflate() method</a>
+ * 
+ */
+public class Java7ZlibInputOutputStream extends XMPPInputOutputStream {
+    private final static Method method;
+    private final static boolean supported;
+    private final static int compressionLevel = Deflater.DEFAULT_STRATEGY;
+
+    static {
+        Method m = null;
+        try {
+            m = Deflater.class.getMethod("deflate", byte[].class, int.class, int.class, int.class);
+        } catch (SecurityException e) {
+        } catch (NoSuchMethodException e) {
+        }
+        method = m;
+        supported = (method != null);
+    }
+
+    public Java7ZlibInputOutputStream() {
+        compressionMethod = "zlib";
+    }
+
+    @Override
+    public boolean isSupported() {
+        return supported;
+    }
+
+    @Override
+    public InputStream getInputStream(InputStream inputStream) {
+        return new InflaterInputStream(inputStream, new Inflater(), 512) {
+            /**
+             * Provide a more InputStream compatible version. A return value of 1 means that it is likely to read one
+             * byte without blocking, 0 means that the system is known to block for more input.
+             * 
+             * @return 0 if no data is available, 1 otherwise
+             * @throws IOException
+             */
+            @Override
+            public int available() throws IOException {
+                /*
+                 * aSmack related remark (where KXmlParser is used):
+                 * This is one of the funny code blocks. InflaterInputStream.available violates the contract of
+                 * InputStream.available, which breaks kXML2.
+                 * 
+                 * I'm not sure who's to blame, oracle/sun for a broken api or the google guys for mixing a sun bug with
+                 * a xml reader that can't handle it....
+                 * 
+                 * Anyway, this simple if breaks suns distorted reality, but helps to use the api as intended.
+                 */
+                if (inf.needsInput()) {
+                    return 0;
+                }
+                return super.available();
+            }
+        };
+    }
+
+    @Override
+    public OutputStream getOutputStream(OutputStream outputStream) {
+        return new DeflaterOutputStream(outputStream, new Deflater(compressionLevel)) {
+            public void flush() throws IOException {
+                if (!supported) {
+                    super.flush();
+                    return;
+                }
+                int count = 0;
+                if (!def.needsInput()) {
+                    do {
+                        count = def.deflate(buf, 0, buf.length);
+                        out.write(buf, 0, count);
+                    } while (count > 0);
+                    out.flush();
+                }
+                try {
+                    do {
+                        count = (Integer) method.invoke(def, buf, 0, buf.length, 2);
+                        out.write(buf, 0, count);
+                    } while (count > 0);
+                } catch (IllegalArgumentException e) {
+                    throw new IOException("Can't flush");
+                } catch (IllegalAccessException e) {
+                    throw new IOException("Can't flush");
+                } catch (InvocationTargetException e) {
+                    throw new IOException("Can't flush");
+                }
+                super.flush();
+            }
+        };
+    }
+
+}

source/org/jivesoftware/smack/compression/JzlibInputOutputStream.java

@@ -0,0 +1,75 @@
+/**
+ * Copyright 2013 Florian Schmaus
+ *
+ * All rights reserved. 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.jivesoftware.smack.compression;
+
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.lang.reflect.Constructor;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+
+/**
+ * This class provides XMPP "zlib" compression with the help of JZLib. Note that jzlib-1.0.7 must be used (i.e. in the
+ * classpath), newer versions won't work!
+ * 
+ * @author Florian Schmaus
+ * @see <a href="http://www.jcraft.com/jzlib/">JZLib</a>
+ * 
+ */
+public class JzlibInputOutputStream extends XMPPInputOutputStream {
+
+    private static Class<?> zoClass = null;
+    private static Class<?> ziClass = null;
+
+    static {
+        try {
+            zoClass = Class.forName("com.jcraft.jzlib.ZOutputStream");
+            ziClass = Class.forName("com.jcraft.jzlib.ZInputStream");
+        } catch (ClassNotFoundException e) {
+        }
+    }
+
+    public JzlibInputOutputStream() {
+        compressionMethod = "zlib";
+    }
+
+    @Override
+    public boolean isSupported() {
+        return (zoClass != null && ziClass != null);
+    }
+
+    @Override
+    public InputStream getInputStream(InputStream inputStream) throws SecurityException, NoSuchMethodException,
+            IllegalArgumentException, IllegalAccessException, InvocationTargetException, InstantiationException {
+        Constructor<?> constructor = ziClass.getConstructor(InputStream.class);
+        Object in = constructor.newInstance(inputStream);
+
+        Method method = ziClass.getMethod("setFlushMode", Integer.TYPE);
+        method.invoke(in, 2);
+        return (InputStream) in;
+    }
+
+    @Override
+    public OutputStream getOutputStream(OutputStream outputStream) throws SecurityException, NoSuchMethodException,
+            IllegalArgumentException, InstantiationException, IllegalAccessException, InvocationTargetException {
+        Constructor<?> constructor = zoClass.getConstructor(OutputStream.class, Integer.TYPE);
+        Object out = constructor.newInstance(outputStream, 9);
+
+        Method method = zoClass.getMethod("setFlushMode", Integer.TYPE);
+        method.invoke(out, 2);
+        return (OutputStream) out;
+    }
+}

source/org/jivesoftware/smack/compression/XMPPInputOutputStream.java

@@ -0,0 +1,33 @@
+/**
+ * Copyright 2013 Florian Schmaus
+ *
+ * All rights reserved. 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.jivesoftware.smack.compression;
+
+import java.io.InputStream;
+import java.io.OutputStream;
+
+public abstract class XMPPInputOutputStream {
+    protected String compressionMethod;
+
+    public String getCompressionMethod() {
+        return compressionMethod;
+    }
+
+    public abstract boolean isSupported();
+
+    public abstract InputStream getInputStream(InputStream inputStream) throws Exception;
+
+    public abstract OutputStream getOutputStream(OutputStream outputStream) throws Exception;
+}

test/config/test-case.example.xml

@@ -26,4 +26,6 @@
     <accountCreationParameters email="test@xcp.localhost" name="test"/>
     -->
 
+    <compressionEnabled>false</compressionEnabled>
+
 </testcase>

test/org/jivesoftware/smack/test/SmackTestCase.java

@@ -64,6 +64,7 @@ public abstract class SmackTestCase extends TestCase {
     private Map<String, String> accountCreationParameters = new HashMap<String, String>();
     private boolean samePassword;
     private List<Integer> createdUserIdx = new ArrayList<Integer>();
+    private boolean compressionEnabled = false;
 
     private String[] usernames;
     private String[] passwords;
@@ -148,7 +149,7 @@ public abstract class SmackTestCase extends TestCase {
     protected XMPPConnection createConnection() {
         // Create the configuration for this new connection
         ConnectionConfiguration config = new ConnectionConfiguration(host, port);
-        config.setCompressionEnabled(Boolean.getBoolean("test.compressionEnabled"));
+        config.setCompressionEnabled(compressionEnabled);
         config.setSendPresence(sendInitialPresence());
         if (getSocketFactory() == null) {
             config.setSocketFactory(getSocketFactory());
@@ -456,6 +457,9 @@ public abstract class SmackTestCase extends TestCase {
                             accountCreationParameters.put(key, value);
                         }
                     }
+                    else if (parser.getName().equals("compressionEnabled")) {
+                        compressionEnabled = "true".equals(parser.nextText());
+                    }
                 }
                 eventType = parser.next();
             }