compression

Assignment 2 Java.iml

@@ -2,10 +2,26 @@
 <module type="JAVA_MODULE" version="4">
   <component name="NewModuleRootManager" inherit-compiler-output="true">
     <exclude-output />
+    <javadoc-paths>
+      <root url="file://$MODULE_DIR$/libs" />
+    </javadoc-paths>
     <content url="file://$MODULE_DIR$">
       <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
     </content>
     <orderEntry type="inheritedJdk" />
     <orderEntry type="sourceFolder" forTests="false" />
+    <orderEntry type="module-library" exported="">
+      <library>
+        <CLASSES>
+          <root url="file://$MODULE_DIR$/libs" />
+        </CLASSES>
+        <JAVADOC />
+        <SOURCES>
+          <root url="file://$MODULE_DIR$/libs" />
+        </SOURCES>
+        <jarDirectory url="file://$MODULE_DIR$/libs" recursive="false" />
+        <jarDirectory url="file://$MODULE_DIR$/libs" recursive="false" type="SOURCES" />
+      </library>
+    </orderEntry>
   </component>
 </module>

src/client/Client.java

@@ -1,5 +1,9 @@
 package client;
 
+import net.jpountz.lz4.LZ4BlockInputStream;
+import net.jpountz.lz4.LZ4BlockOutputStream;
+import net.jpountz.lz4.LZ4FrameInputStream;
+import net.jpountz.lz4.LZ4FrameOutputStream;
 import server.Server;
 import shared.ExceptionLogger;
 import shared.FileHeader;

src/server/Connection.java

@@ -1,5 +1,10 @@
 package server;
 
+import net.jpountz.lz4.LZ4BlockInputStream;
+import net.jpountz.lz4.LZ4BlockOutputStream;
+import net.jpountz.lz4.LZ4FrameInputStream;
+import net.jpountz.lz4.LZ4FrameOutputStream;
+import shared.ExceptionLogger;
 import shared.FileHeader;
 
 import java.io.*;
@@ -18,7 +23,8 @@ public class Connection extends Thread {
         try {
             out = new DataOutputStream(new BufferedOutputStream(clientSocket.getOutputStream()));
             in = new DataInputStream(new BufferedInputStream(clientSocket.getInputStream()));
-        } catch (Exception ignored) {
+        } catch (Exception e) {
+            ExceptionLogger.log(e);
         }
     }
 

src/shared/FileHeader.java

@@ -1,6 +1,10 @@
 package shared;
 
 import client.Client;
+import net.jpountz.lz4.LZ4Compressor;
+import net.jpountz.lz4.LZ4Factory;
+import net.jpountz.lz4.LZ4FastDecompressor;
+import net.jpountz.lz4.LZ4SafeDecompressor;
 
 import java.io.*;
 import java.nio.file.Files;
@@ -8,7 +12,11 @@ import java.nio.file.Paths;
 
 public class FileHeader {
 
-    private static final int READER_SIZE = 8192;
+    public static final int READER_SIZE = 8192;
+
+    private static final LZ4Factory factory = LZ4Factory.fastestInstance();
+    private static final LZ4Compressor compressor = factory.highCompressor();
+    private static final LZ4FastDecompressor decompressor = factory.fastDecompressor();
 
     public enum COMMAND {
         WRITE((byte) 1);
@@ -42,15 +50,24 @@ public class FileHeader {
             writer.writeUTF(relative_path);
 
             while (reader.available() > 0) {
+                // read / write files in chunks
                 int read = Integer.min(reader.available(), READER_SIZE);
                 byte[] bytes = new byte[read];
 
                 int amount = reader.read(bytes);
                 if (amount <= 0)
                     break;
-                System.out.println("Writing " + amount + "  bytes");
+
+                // apply compression
+                int maxCompressedLength = compressor.maxCompressedLength(bytes.length);
+                byte[] compressed = new byte[maxCompressedLength];
+                int compressedLength = compressor.compress(bytes, 0, bytes.length, compressed, 0, maxCompressedLength);
+
+                System.out.println("Writing " + compressedLength + "  bytes");
                 writer.writeInt(amount);
-                writer.write(bytes, 0, amount);
+                writer.writeInt(compressedLength);
+                writer.write(compressed, 0, compressedLength);
+                writer.flush();
             }
             reader.close();
             writer.writeInt(0);
@@ -75,13 +92,20 @@ public class FileHeader {
             System.out.println("Writing to file: " + path);
 
             DataOutputStream writer = new DataOutputStream(new BufferedOutputStream(Files.newOutputStream(Paths.get(path))));
-            int size = 0;
+            int uncompressed_size = 0;
-            while ((size = reader.readInt()) > 0) {
+            while ((uncompressed_size = reader.readInt()) > 0) {
-                byte[] data = new byte[size];
+                int compressed_size = reader.readInt();
-                int amount = reader.read(data, 0, size);
+                byte[] data = new byte[compressed_size];
-                writer.write(data, 0, amount);
+                int amount = reader.read(data, 0, compressed_size);
+
+                byte[] restored = new byte[uncompressed_size];
+
+                int len = decompressor.decompress(data, 0, restored, 0, uncompressed_size);
+
+                writer.write(restored, 0, uncompressed_size);
             }
             writer.flush();
+            writer.close();
         } catch (Exception e){
             ExceptionLogger.log(e);
         }