Now we use a StorageEntry class to send data accross peers

Out KadContent interface also now specifies a set of methods to force it's subclasses to do their own toByte conversions

src/kademlia/Kademlia.java

@@ -19,6 +19,7 @@ import kademlia.core.KadConfiguration;
 import kademlia.core.KadServer;
 import kademlia.dht.DHT;
 import kademlia.dht.KadContent;
+import kademlia.dht.StorageEntry;
 import kademlia.exceptions.RoutingException;
 import kademlia.message.MessageFactory;
 import kademlia.node.Node;
@@ -280,7 +281,7 @@ public class Kademlia
      *
      * @throws java.io.IOException
      */
-    public List<KadContent> get(GetParameter param, int numResultsReq) throws NoSuchElementException, IOException
+    public List<StorageEntry> get(GetParameter param, int numResultsReq) throws NoSuchElementException, IOException
     {
         List contentFound;
         if (this.dht.contains(param))

src/kademlia/core/GetParameter.java

@@ -19,26 +19,16 @@ public class GetParameter
     private String ownerId = null;
     private String type = null;
 
-    /**
-     * Construct a GetParameter to search for data by NodeId
-     *
-     * @param key
-     */
-    public GetParameter(NodeId key)
-    {
-        this.key = key;
-    }
-
     /**
      * Construct a GetParameter to search for data by NodeId and owner
      *
      * @param key
-     * @param owner
+     * @param type
      */
-    public GetParameter(NodeId key, String owner)
+    public GetParameter(NodeId key, String type)
     {
-        this(key);
-        this.ownerId = owner;
+        this.key = key;
+        this.type = type;
     }
 
     /**

src/kademlia/dht/DHT.java

@@ -27,7 +27,7 @@ public class DHT
 {
 
     private transient StorageEntryManager entriesManager;
-    private transient KadSerializer<KadContent> contentSerializer = null;
+    private transient KadSerializer<StorageEntry> serializer = null;
     private transient KadConfiguration config;
 
     private final String ownerId;
@@ -62,14 +62,14 @@ public class DHT
      *
      * @return The new ContentSerializer
      */
-    public KadSerializer<KadContent> getContentSerializer()
+    public KadSerializer<StorageEntry> getSerializer()
     {
-        if (null == contentSerializer)
+        if (null == serializer)
         {
-            contentSerializer = new JsonSerializer<>();
+            serializer = new JsonSerializer<>();
         }
 
-        return contentSerializer;
+        return serializer;
     }
 
     /**
@@ -79,22 +79,20 @@ public class DHT
      *
      * @throws java.io.IOException
      */
-    public void store(KadContent content) throws IOException
+    public void store(StorageEntry content) throws IOException
     {
         /* Keep track of this content in the entries manager */
         try
         {
-            StorageEntryMetadata sEntry = this.entriesManager.put(content);
+            StorageEntryMetadata sEntry = this.entriesManager.put(content.getContentMetadata());
 
             /* Now we store the content locally in a file */
-            String contentStorageFolder = this.getContentStorageFolderName(content.getKey());
+            String contentStorageFolder = this.getContentStorageFolderName(content.getContentMetadata().getKey());
 
             try (FileOutputStream fout = new FileOutputStream(contentStorageFolder + File.separator + sEntry.hashCode() + ".kct");
                     DataOutputStream dout = new DataOutputStream(fout))
             {
-                byte[] data = content.toBytes();
-                dout.writeInt(data.length);
-                dout.write(data);
+                this.getSerializer().write(content, dout);
             }
         }
         catch (ContentExistException e)
@@ -103,6 +101,11 @@ public class DHT
         }
     }
 
+    public void store(KadContent content) throws IOException
+    {
+        this.store(new StorageEntry(content));
+    }
+
     /**
      * Retrieves a Content from local storage
      *
@@ -111,15 +114,11 @@ public class DHT
      *
      * @return A KadContent object
      */
-    private byte[] retrieve(NodeId key, int hashCode) throws FileNotFoundException, IOException, ClassNotFoundException
+    private StorageEntry retrieve(NodeId key, int hashCode) throws FileNotFoundException, IOException, ClassNotFoundException
     {
         String folder = this.getContentStorageFolderName(key);
         DataInputStream din = new DataInputStream(new FileInputStream(folder + File.separator + hashCode + ".kct"));
-        int length = din.readInt();
-
-        byte[] data = new byte[length];
-        din.read(data);
-        return data;
+        return this.getSerializer().read(din);
     }
 
     /**
@@ -143,7 +142,7 @@ public class DHT
      *
      * @throws java.io.IOException
      */
-    public byte[] get(StorageEntryMetadata entry) throws IOException, NoSuchElementException
+    public StorageEntry get(StorageEntryMetadata entry) throws IOException, NoSuchElementException
     {
         try
         {
@@ -172,7 +171,7 @@ public class DHT
      *
      * @throws java.io.IOException
      */
-    public byte[] get(GetParameter param) throws NoSuchElementException, IOException
+    public StorageEntry get(GetParameter param) throws NoSuchElementException, IOException
     {
         /* Load a KadContent if any exist for the given criteria */
         try

src/kademlia/dht/KadContent.java

@@ -1,16 +1,19 @@
 package kademlia.dht;
 
+import com.google.gson.Gson;
 import kademlia.node.NodeId;
 
 /**
  * Any piece of content that needs to be stored on the DHT
  *
  * @author Joshua Kissoon
+ * @param <T>
+ *
  * @since 20140224
  */
 public interface KadContent
 {
-
+    
     /**
      * @return NodeId The DHT key for this content
      */
@@ -42,13 +45,7 @@ public interface KadContent
      */
     public String getOwnerId();
 
-    public default byte[] toBytes()
-    {
-        return new byte[2];
-    }
+    public byte[] toBytes();
 
-    public default void fromBytes(byte[] data)
-    {
-
-    }
+    public KadContent fromBytes(byte[] data);
 }

src/kademlia/dht/StorageEntry.java

@@ -8,16 +8,28 @@ package kademlia.dht;
  */
 public class StorageEntry
 {
-    private byte[] content;
-    private StorageEntryMetadata metadata;
-    
+
+    private final byte[] content;
+    private final StorageEntryMetadata metadata;
+
     public StorageEntry(KadContent content)
     {
-        
+        this(content, new StorageEntryMetadata(content));
     }
-    
+
     public StorageEntry(KadContent content, StorageEntryMetadata metadata)
     {
-        this.content = content.g
+        this.content = content.toBytes();
+        this.metadata = metadata;
+    }
+
+    public byte[] getContent()
+    {
+        return this.content;
+    }
+
+    public StorageEntryMetadata getContentMetadata()
+    {
+        return this.metadata;
     }
 }

src/kademlia/message/ContentMessage.java

@@ -3,7 +3,7 @@ package kademlia.message;
 import java.io.DataInputStream;
 import java.io.DataOutputStream;
 import java.io.IOException;
-import kademlia.dht.KadContent;
+import kademlia.dht.StorageEntry;
 import kademlia.node.Node;
 import kademlia.serializer.JsonSerializer;
 
@@ -18,7 +18,7 @@ public class ContentMessage implements Message
 
     public static final byte CODE = 0x04;
 
-    private byte[] content;
+    private StorageEntry content;
     private Node origin;
 
     /**
@@ -26,7 +26,7 @@ public class ContentMessage implements Message
      * @param content The content to be stored
      *
      */
-    public ContentMessage(Node origin, byte[] content)
+    public ContentMessage(Node origin, StorageEntry content)
     {
         this.content = content;
         this.origin = origin;
@@ -43,8 +43,7 @@ public class ContentMessage implements Message
         this.origin.toStream(out);
 
         /* Serialize the KadContent, then send it to the stream */
-        out.writeInt(content.length);
-        out.write(content);
+        new JsonSerializer<StorageEntry>().write(content, out);
     }
 
     @Override
@@ -52,9 +51,14 @@ public class ContentMessage implements Message
     {
         this.origin = new Node(in);
 
-        final int length = in.readInt();
-        this.content = new byte[length];
-        in.read(content);
+        try
+        {
+            this.content = new JsonSerializer<StorageEntry>().read(in);
+        }
+        catch (ClassNotFoundException e)
+        {
+            System.err.println("ClassNotFoundException when reading StorageEntry; Message: " + e.getMessage());
+        }
     }
 
     public Node getOrigin()
@@ -62,7 +66,7 @@ public class ContentMessage implements Message
         return this.origin;
     }
 
-    public byte[] getContent()
+    public StorageEntry getContent()
     {
         return this.content;
     }

src/kademlia/message/StoreContentMessage.java

@@ -4,6 +4,7 @@ import java.io.DataInputStream;
 import java.io.DataOutputStream;
 import java.io.IOException;
 import kademlia.dht.KadContent;
+import kademlia.dht.StorageEntry;
 import kademlia.node.Node;
 import kademlia.serializer.JsonSerializer;
 
@@ -18,7 +19,7 @@ public class StoreContentMessage implements Message
 
     public static final byte CODE = 0x08;
 
-    private KadContent content;
+    private StorageEntry content;
     private Node origin;
 
     /**
@@ -26,7 +27,7 @@ public class StoreContentMessage implements Message
      * @param content The content to be stored
      *
      */
-    public StoreContentMessage(Node origin, KadContent content)
+    public StoreContentMessage(Node origin, StorageEntry content)
     {
         this.content = content;
         this.origin = origin;
@@ -43,7 +44,7 @@ public class StoreContentMessage implements Message
         this.origin.toStream(out);
 
         /* Serialize the KadContent, then send it to the stream */
-        new JsonSerializer<KadContent>().write(content, out);
+        new JsonSerializer<StorageEntry>().write(content, out);
     }
 
     @Override
@@ -52,7 +53,7 @@ public class StoreContentMessage implements Message
         this.origin = new Node(in);
         try
         {
-            this.content = new JsonSerializer<KadContent>().read(in);
+            this.content = new JsonSerializer<StorageEntry>().read(in);
         }
         catch (ClassNotFoundException e)
         {
@@ -65,7 +66,7 @@ public class StoreContentMessage implements Message
         return this.origin;
     }
 
-    public KadContent getContent()
+    public StorageEntry getContent()
     {
         return this.content;
     }

src/kademlia/operation/ContentLookupOperation.java

@@ -12,7 +12,7 @@ import java.util.TreeMap;
 import kademlia.core.GetParameter;
 import kademlia.core.KadConfiguration;
 import kademlia.core.KadServer;
-import kademlia.dht.KadContent;
+import kademlia.dht.StorageEntry;
 import kademlia.exceptions.RoutingException;
 import kademlia.exceptions.UnknownMessageException;
 import kademlia.message.ContentLookupMessage;
@@ -42,7 +42,7 @@ public class ContentLookupOperation implements Operation, Receiver
     private final KadServer server;
     private final Node localNode;
     private final GetParameter params;
-    private final List<KadContent> contentFound;
+    private final List<StorageEntry> contentFound;
     private final int numResultsReq;
     private final KadConfiguration config;
 
@@ -250,7 +250,7 @@ public class ContentLookupOperation implements Operation, Receiver
             this.localNode.getRoutingTable().insert(msg.getOrigin());
 
             /* Get the Content and check if it satisfies the required parameters */
-            KadContent content = msg.getContent();
+            StorageEntry content = msg.getContent();
             System.out.println("Content Received: " + content);
 
             /*@todo Check if the content matches the given criteria */
@@ -313,7 +313,7 @@ public class ContentLookupOperation implements Operation, Receiver
     /**
      * @return The list of all content found during the lookup operation
      */
-    public List<KadContent> getContentFound()
+    public List<StorageEntry> getContentFound()
     {
         return this.contentFound;
     }

src/kademlia/operation/ContentRefreshOperation.java

@@ -2,7 +2,6 @@ package kademlia.operation;
 
 import java.io.IOException;
 import java.util.List;
-import kademlia.core.DefaultConfiguration;
 import kademlia.core.KadConfiguration;
 import kademlia.core.KadServer;
 import kademlia.dht.DHT;

src/kademlia/operation/StoreOperation.java

@@ -6,6 +6,7 @@ import kademlia.core.KadConfiguration;
 import kademlia.core.KadServer;
 import kademlia.dht.DHT;
 import kademlia.dht.KadContent;
+import kademlia.dht.StorageEntry;
 import kademlia.message.Message;
 import kademlia.message.StoreContentMessage;
 import kademlia.node.Node;
@@ -50,7 +51,7 @@ public class StoreOperation implements Operation
         List<Node> nodes = ndlo.getClosestNodes();
 
         /* Create the message */
-        Message msg = new StoreContentMessage(this.localNode, this.content);
+        Message msg = new StoreContentMessage(this.localNode, new StorageEntry(this.content));
 
         /*Store the message on all of the K-Nodes*/
         for (Node n : nodes)

src/kademlia/tests/AutoRefreshOperationTest.java

@@ -25,7 +25,7 @@ public class AutoRefreshOperationTest
             final Kademlia kad2 = new Kademlia("Crystal", new NodeId("AJDHR678947584567464"), 4585);
             final Kademlia kad3 = new Kademlia("Shameer", new NodeId("AS84k6789KRNS45KFJ8W"), 8104);
             final Kademlia kad4 = new Kademlia("Lokesh.", new NodeId("ASF45678947A845674GG"), 8335);
-            final Kademlia kad5 = new Kademlia("Chandu.", new NodeId("AS84RUD894758456dyrj"), 13345);
+            final Kademlia kad5 = new Kademlia("Chandu.", new NodeId("AS84kUD894758456dyrj"), 13345);
 
             /* Connecting nodes */
             System.out.println("Connecting Nodes");

src/kademlia/tests/ContentSendingTest.java

@@ -4,7 +4,7 @@ import java.io.IOException;
 import java.util.List;
 import kademlia.core.GetParameter;
 import kademlia.Kademlia;
-import kademlia.dht.KadContent;
+import kademlia.dht.StorageEntry;
 import kademlia.node.NodeId;
 
 /**
@@ -37,14 +37,15 @@ public class ContentSendingTest
              * Lets retrieve the content
              */
             System.out.println("Retrieving Content");
-            GetParameter gp = new GetParameter(c.getKey());
+            GetParameter gp = new GetParameter(c.getKey(), DHTContentImpl.TYPE);
             gp.setType(DHTContentImpl.TYPE);
             gp.setOwnerId(c.getOwnerId());
             System.out.println("Get Parameter: " + gp);
-            List<KadContent> conte = kad2.get(gp, 1);
-            for (KadContent cc : conte)
+            List<StorageEntry> conte = kad2.get(gp, 4);
+            for (StorageEntry cc : conte)
             {
-                System.out.println("Content Found: " + cc);
+                System.out.println("Content Found: " + new DHTContentImpl().fromBytes(cc.getContent()));
+                System.out.println("Content Metadata: " + cc.getContentMetadata());
             }
 
         }

src/kademlia/tests/DHTContentImpl.java

@@ -1,5 +1,6 @@
 package kademlia.tests;
 
+import com.google.gson.Gson;
 import kademlia.dht.KadContent;
 import kademlia.node.NodeId;
 
@@ -12,17 +13,20 @@ import kademlia.node.NodeId;
 public class DHTContentImpl implements KadContent
 {
 
-    private final NodeId key;
+    private NodeId key;
     private String data;
-    private final String ownerId;
-    private final long createTs, updateTs;
-
-    public static final String TYPE = "DHTContentImpl";
+    private String ownerId;
+    private long createTs, updateTs;
 
     
     {
         this.createTs = this.updateTs = System.currentTimeMillis() / 1000L;
     }
+    
+    public DHTContentImpl()
+    {
+        
+    }
 
     public DHTContentImpl(String ownerId, String data)
     {
@@ -42,11 +46,6 @@ public class DHTContentImpl implements KadContent
         this.data = newData;
     }
 
-    public String toBytes()
-    {
-        return this.data;
-    }
-
     @Override
     public NodeId getKey()
     {
@@ -76,6 +75,22 @@ public class DHTContentImpl implements KadContent
     {
         return this.updateTs;
     }
+    
+    
+    @Override
+    public byte[] toBytes()
+    {
+        Gson gson = new Gson();
+        return gson.toJson(this).getBytes();
+    }
+    
+    @Override
+    public DHTContentImpl fromBytes(byte[] data)
+    {
+        Gson gson = new Gson();
+        DHTContentImpl val = gson.fromJson(new String(data), DHTContentImpl.class);
+        return val;
+    }
 
     @Override
     public String toString()

src/kademlia/tests/RefreshOperationTest.java

@@ -4,7 +4,7 @@ import java.io.IOException;
 import java.util.List;
 import kademlia.core.GetParameter;
 import kademlia.Kademlia;
-import kademlia.dht.KadContent;
+import kademlia.dht.StorageEntry;
 import kademlia.node.NodeId;
 
 /**
@@ -30,10 +30,10 @@ public class RefreshOperationTest
             kad2.put(c);
 
             /* Lets retrieve the content */
-            GetParameter gp = new GetParameter(c.getKey());
+            GetParameter gp = new GetParameter(c.getKey(), DHTContentImpl.TYPE);
             gp.setType(DHTContentImpl.TYPE);
             gp.setOwnerId(c.getOwnerId());
-            List<KadContent> conte = kad2.get(gp, 1);
+            List<StorageEntry> conte = kad2.get(gp, 1);
 
             kad2.refresh();
         }

src/kademlia/tests/SaveStateTest2.java

@@ -3,7 +3,7 @@ package kademlia.tests;
 import java.util.List;
 import kademlia.Kademlia;
 import kademlia.core.GetParameter;
-import kademlia.dht.KadContent;
+import kademlia.dht.StorageEntry;
 import kademlia.node.NodeId;
 
 /**
@@ -53,11 +53,11 @@ public class SaveStateTest2
 
             /* Trying to get a content stored on the restored node */
             GetParameter gp = new GetParameter(c.getKey(), kad2.getOwnerId(), c.getType());
-            List<KadContent> content = kad2.get(gp, 1);
+            List<StorageEntry> content = kad2.get(gp, 1);
 
             if (!content.isEmpty())
             {
-                DHTContentImpl cc = (DHTContentImpl) content.get(0);
+                DHTContentImpl cc = new DHTContentImpl().fromBytes(content.get(0).getContent());
                 System.out.println("Content received: " + cc);
             }
             else