Added BerkeleyDB as storage backend, added support of Kotlin lang, fixed some bugs

.idea/gradle.xml

@@ -3,9 +3,6 @@
   <component name="GradleSettings">
     <option name="linkedExternalProjectsSettings">
       <GradleProjectSettings>
-        <compositeConfiguration>
-          <compositeBuild compositeDefinitionSource="SCRIPT" />
-        </compositeConfiguration>
         <option name="distributionType" value="DEFAULT_WRAPPED" />
         <option name="externalProjectPath" value="$PROJECT_DIR$" />
         <option name="modules">

app/build.gradle

@@ -1,4 +1,6 @@
 apply plugin: 'com.android.application'
+apply plugin: 'kotlin-android-extensions'
+apply plugin: 'kotlin-android'
 
 android {
     compileSdkVersion 28
@@ -52,4 +54,8 @@ dependencies {
     implementation group: 'org.springframework.security', name: 'spring-security-crypto', version: '3.1.0.RELEASE'
     implementation 'de.hdodenhof:circleimageview:3.0.0'
     implementation group: 'org.objenesis', name: 'objenesis', version: '2.6'
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlin_version"
+}
+repositories {
+    mavenCentral()
 }

app/src/main/java/io/github/chronosx88/influence/helpers/DataSerializerEx.java

@@ -1,192 +0,0 @@
-package io.github.chronosx88.influence.helpers;
-
-import android.util.Log;
-
-import net.tomp2p.connection.SignatureFactory;
-import net.tomp2p.peers.Number160;
-import net.tomp2p.storage.AlternativeCompositeByteBuf;
-import net.tomp2p.storage.Data;
-
-import org.mapdb.Serializer;
-
-import java.io.DataInput;
-import java.io.DataOutput;
-import java.io.File;
-import java.io.FileNotFoundException;
-import java.io.IOException;
-import java.io.RandomAccessFile;
-import java.io.Serializable;
-import java.nio.ByteBuffer;
-import java.nio.MappedByteBuffer;
-import java.nio.channels.FileChannel;
-import java.security.InvalidKeyException;
-import java.security.KeyPair;
-import java.security.SignatureException;
-
-import io.netty.buffer.ByteBuf;
-import io.netty.buffer.Unpooled;
-
-public class DataSerializerEx implements Serializer<Data>, Serializable {
-
-    private static final long serialVersionUID = 1428836065493792295L;
-    //TODO: test the performance impact
-    private static final int MAX_SIZE = 10 * 1024;
-
-    private File path;
-    private SignatureFactory signatureFactory;
-    final private static KeyPairManager keyPairManager = new KeyPairManager();
-
-    public DataSerializerEx() { }
-
-    public DataSerializerEx(File path, SignatureFactory signatureFactory) {
-        this.path = path;
-        this.signatureFactory = signatureFactory;
-    }
-
-    @Override
-    public void serialize(DataOutput out, Data value) throws IOException {
-        if (value.length() > MAX_SIZE) {
-            // header, 1 means stored on disk in a file
-            out.writeByte(1);
-            serializeFile(out, value);
-        } else {
-            // header, 0 means stored on disk with MapDB
-            out.writeByte(0);
-            serializeMapDB(out, value);
-        }
-    }
-
-    private void serializeMapDB(DataOutput out, Data value) throws IOException {
-        KeyPair keyPair =  keyPairManager.getKeyPair("mainKeyForSign");
-        value.sign(keyPair);
-        AlternativeCompositeByteBuf acb = AlternativeCompositeByteBuf.compBuffer(AlternativeCompositeByteBuf.UNPOOLED_HEAP);
-        // store data to disk
-        // header first
-        value.encodeHeader(acb, signatureFactory);
-        write(out, acb.nioBuffers());
-        acb.skipBytes(acb.writerIndex());
-        // next data - no need to copy to another buffer, just take the data
-        // from memory
-        write(out, value.toByteBuffers());
-        // rest
-        try {
-            value.encodeDone(acb, signatureFactory);
-            write(out, acb.nioBuffers());
-        } catch (InvalidKeyException e) {
-            throw new IOException(e);
-        } catch (SignatureException e) {
-            throw new IOException(e);
-        }
-    }
-
-    private void serializeFile(DataOutput out, Data value) throws IOException, FileNotFoundException {
-        Number160 hash = value.hash();
-        // store file name
-        out.write(hash.toByteArray());
-        // store as external file, create path
-        RandomAccessFile file = null;
-        FileChannel rwChannel = null;
-        try {
-            file = new RandomAccessFile(new File(path, hash.toString()), "rw");
-            rwChannel = file.getChannel();
-            AlternativeCompositeByteBuf acb = AlternativeCompositeByteBuf.compBuffer(AlternativeCompositeByteBuf.UNPOOLED_HEAP);
-            // store data to disk
-            // header first
-            value.encodeHeader(acb, signatureFactory);
-            rwChannel.write(acb.nioBuffers());
-            // next data - no need to copy to another buffer, just take the
-            // data from memory
-            rwChannel.write(value.toByteBuffers());
-            // rest
-            try {
-                value.encodeDone(acb, signatureFactory);
-                rwChannel.write(acb.nioBuffers());
-            } catch (InvalidKeyException e) {
-                throw new IOException(e);
-            } catch (SignatureException e) {
-                throw new IOException(e);
-            }
-        } finally {
-
-            if (rwChannel != null) {
-                rwChannel.close();
-            }
-            if (file != null) {
-                file.close();
-            }
-        }
-    }
-
-    private void write(DataOutput out, ByteBuffer[] nioBuffers) throws IOException {
-        final int length = nioBuffers.length;
-        for(int i=0;i < length; i++) {
-            int remaining = nioBuffers[i].remaining();
-            if(nioBuffers[i].hasArray()) {
-                out.write(nioBuffers[i].array(), nioBuffers[i].arrayOffset(), remaining);
-            } else {
-                byte[] me = new byte[remaining];
-                nioBuffers[i].get(me);
-                out.write(me);
-            }
-        }
-    }
-
-    @Override
-    public Data deserialize(DataInput in, int available) throws IOException {
-        int header = in.readByte();
-        if(header == 1) {
-            return deserializeFile(in);
-        } else if(header == 0) {
-            return deserializeMapDB(in);
-        } else {
-            //throw new IOException("unexpected header: " + header);
-            return null;
-        }
-    }
-
-    private Data deserializeMapDB(DataInput in) throws IOException {
-        ByteBuf buf = Unpooled.buffer();
-        Data data = null;
-        while(data == null) {
-            buf.writeByte(in.readByte());
-            data = Data.decodeHeader(buf, signatureFactory);
-        }
-        int len = data.length();
-        byte me[] = new byte[len];
-        in.readFully(me);
-        buf = Unpooled.wrappedBuffer(me);
-        boolean retVal = data.decodeBuffer(buf);
-        if(!retVal) {
-            throw new IOException("data could not be read");
-        }
-        retVal = data.decodeDone(buf, signatureFactory);
-        if(!retVal) {
-            //throw new IOException("signature could not be read");
-            Log.e("DataSerializerEx", "# Signature could not be read!");
-        }
-
-        return data;
-    }
-
-    private Data deserializeFile(DataInput in) throws IOException, FileNotFoundException {
-        byte[] me = new byte[Number160.BYTE_ARRAY_SIZE];
-        in.readFully(me);
-        Number160 hash = new Number160(me);
-        RandomAccessFile file = new RandomAccessFile(new File(path, hash.toString()), "r");
-        FileChannel inChannel = file.getChannel();
-        MappedByteBuffer buffer = inChannel.map(FileChannel.MapMode.READ_ONLY, 0, inChannel.size());
-        buffer.load();
-        ByteBuf buf = Unpooled.wrappedBuffer(buffer);
-        Data data = Data.decodeHeader(buf, signatureFactory);
-        data.decodeBuffer(buf);
-        data.decodeDone(buf, signatureFactory);
-        file.close();
-        return data;
-    }
-
-    @Override
-    public int fixedSize() {
-        return -1;
-    }
-}
-

app/src/main/java/io/github/chronosx88/influence/helpers/DataSerializerEx.kt

@@ -0,0 +1,104 @@
+package io.github.chronosx88.influence.helpers
+
+import android.util.Log
+
+import com.sleepycat.bind.EntryBinding
+import com.sleepycat.je.DatabaseEntry
+
+import net.tomp2p.connection.SignatureFactory
+import net.tomp2p.storage.AlternativeCompositeByteBuf
+import net.tomp2p.storage.Data
+
+import java.io.ByteArrayInputStream
+import java.io.ByteArrayOutputStream
+import java.io.IOException
+import java.io.OutputStream
+import java.io.Serializable
+import java.nio.ByteBuffer
+import java.security.InvalidKeyException
+import java.security.SignatureException
+
+import io.netty.buffer.Unpooled
+
+class DataSerializerEx(private val signatureFactory: SignatureFactory) : EntryBinding<Data>, Serializable {
+    private val LOG_TAG = "DataSerializerEx"
+
+    override fun entryToObject(databaseEntry: DatabaseEntry): Data? {
+        if (databaseEntry.data == null) {
+            return null
+        }
+        val inputStream = ByteArrayInputStream(databaseEntry.data)
+        var buf = Unpooled.buffer()
+        var data: Data? = null
+        while (data == null) {
+            buf.writeByte(inputStream.read())
+            data = Data.decodeHeader(buf, signatureFactory)
+        }
+        val len = data.length()
+        val me = ByteArray(len)
+        try {
+            inputStream.read(me)
+        } catch (e: IOException) {
+            e.printStackTrace()
+        }
+
+        buf = Unpooled.wrappedBuffer(me)
+        var retVal = data.decodeBuffer(buf)
+        if (!retVal) {
+            Log.e(LOG_TAG, "# ERROR: Data could not be deserialized!")
+        }
+        retVal = data.decodeDone(buf, signatureFactory)
+        if (!retVal) {
+            Log.e(LOG_TAG, "# ERROR: Signature could not be read!")
+        }
+        return data
+    }
+
+    override fun objectToEntry(data: Data, databaseEntry: DatabaseEntry) {
+        val forSigningKP = keyPairManager.getKeyPair("mainSigningKeyPair")
+        data.sign(forSigningKP)
+        val out = ByteArrayOutputStream()
+        val acb = AlternativeCompositeByteBuf.compBuffer(AlternativeCompositeByteBuf.UNPOOLED_HEAP)
+        try {
+            // header first
+            data.encodeHeader(acb, signatureFactory)
+            writeData(out, acb.nioBuffers())
+            acb.skipBytes(acb.writerIndex())
+            // next data - no need to copy to another buffer, just take the data
+            // from memory
+            writeData(out, data.toByteBuffers())
+            // rest
+            data.encodeDone(acb, signatureFactory)
+            writeData(out, acb.nioBuffers())
+        } catch (e: SignatureException) {
+            e.printStackTrace()
+        } catch (e: InvalidKeyException) {
+            e.printStackTrace()
+        } catch (e: IOException) {
+            e.printStackTrace()
+        }
+
+        databaseEntry.data = out.toByteArray()
+    }
+
+    @Throws(IOException::class)
+    private fun writeData(out: OutputStream, nioBuffers: Array<ByteBuffer>) {
+        val length = nioBuffers.size
+        for (i in 0 until length) {
+            val remaining = nioBuffers[i].remaining()
+            if (nioBuffers[i].hasArray()) {
+                out.write(nioBuffers[i].array(), nioBuffers[i].arrayOffset(), remaining)
+            } else {
+                val me = ByteArray(remaining)
+                nioBuffers[i].get(me)
+                out.write(me)
+            }
+        }
+    }
+
+    companion object {
+        private const val serialVersionUID = 1428836065493792295L
+        private val keyPairManager = KeyPairManager()
+    }
+}
+

app/src/main/java/io/github/chronosx88/influence/helpers/KeyPairManager.java

@@ -10,12 +10,14 @@ import java.security.NoSuchAlgorithmException;
 
 public class KeyPairManager {
     private File keyPairDir;
+    private Serializer<KeyPair> serializer;
 
     public KeyPairManager() {
         this.keyPairDir = new File(AppHelper.getContext().getFilesDir().getAbsoluteFile(), "keyPairs");
         if(!this.keyPairDir.exists()) {
             this.keyPairDir.mkdir();
         }
+        this.serializer = new Serializer<>();
     }
 
     public KeyPair openMainKeyPair() {
@@ -39,7 +41,7 @@ public class KeyPairManager {
             byte[] serializedKeyPair = new byte[(int) keyPairFile.length()];
             inputStream.read(serializedKeyPair);
             inputStream.close();
-            keyPair = (KeyPair) Serializer.deserialize(serializedKeyPair);
+            keyPair = serializer.deserialize(serializedKeyPair);
         } catch (IOException e) {
             e.printStackTrace();
         }
@@ -52,7 +54,7 @@ public class KeyPairManager {
             keyPairFile.createNewFile();
             keyPair = KeyPairGenerator.getInstance("DSA").generateKeyPair();
             FileOutputStream outputStream = new FileOutputStream(keyPairFile);
-            outputStream.write(Serializer.serialize(keyPair));
+            outputStream.write(serializer.serialize(keyPair));
             outputStream.close();
         } catch (IOException | NoSuchAlgorithmException e) {
             e.printStackTrace();
@@ -65,7 +67,7 @@ public class KeyPairManager {
         if(!keyPairFile.exists()) {
             try {
                 FileOutputStream outputStream = new FileOutputStream(keyPairFile);
-                outputStream.write(Serializer.serialize(keyPair));
+                outputStream.write(serializer.serialize(keyPair));
                 outputStream.close();
             } catch (IOException e) {
                 e.printStackTrace();

app/src/main/java/io/github/chronosx88/influence/helpers/P2PUtils.java

@@ -54,7 +54,7 @@ public class P2PUtils {
                 .all()
                 .start()
                 .awaitUninterruptibly();
-        if(!futureGet.isEmpty()) {
+        if(futureGet != null && !futureGet.isEmpty()) {
             return futureGet.dataMap();
         }
         return null;

app/src/main/java/io/github/chronosx88/influence/helpers/PrepareData.java

@@ -1,19 +0,0 @@
-package io.github.chronosx88.influence.helpers;
-
-import org.springframework.security.crypto.codec.Base64;
-
-import java.io.Serializable;
-
-public class PrepareData {
-    public static <T> String prepareToStore(T object) {
-        if(object instanceof Serializable) {
-            byte[] serializedObject = Serializer.serialize(object);
-            return new String(Base64.encode(serializedObject));
-        }
-        return null;
-    }
-
-    public static Object prepareFromStore(String object) {
-        return Serializer.deserialize(Base64.decode(object.getBytes()));
-    }
-}

app/src/main/java/io/github/chronosx88/influence/helpers/Serializer.java

@@ -1,17 +1,20 @@
 package io.github.chronosx88.influence.helpers;
 
+import com.sleepycat.bind.EntryBinding;
+import com.sleepycat.je.DatabaseEntry;
+
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.ObjectInputStream;
 import java.io.ObjectOutputStream;
 
-public class Serializer {
+public class Serializer<T> implements EntryBinding<T> {
-    public static byte[] serialize(Object object) {
+    public byte[] serialize(T object) {
         ByteArrayOutputStream byteArray = new ByteArrayOutputStream();
         try {
             ObjectOutputStream objectOutputStream = new ObjectOutputStream(byteArray);
-            objectOutputStream.writeObject(object);;
+            objectOutputStream.writeObject(object);
             objectOutputStream.close();
         } catch (IOException e) {
             e.printStackTrace();
@@ -19,19 +22,7 @@ public class Serializer {
         return byteArray.toByteArray();
     }
 
-    public static Object deserialize(String serializedObject) {
+    public T deserialize(byte[] serializedObject) {
-        ByteArrayInputStream inputStream = new ByteArrayInputStream(serializedObject.getBytes());
-        Object object = null;
-        try {
-            ObjectInputStream objectInputStream = new ObjectInputStream(inputStream);
-            object = objectInputStream.readObject();
-        } catch (ClassNotFoundException | IOException e) {
-            e.printStackTrace();
-        }
-        return object;
-    }
-
-    public static Object deserialize(byte[] serializedObject) {
         if(serializedObject == null)
             return null;
         ByteArrayInputStream inputStream = new ByteArrayInputStream(serializedObject);
@@ -42,6 +33,16 @@ public class Serializer {
         } catch (ClassNotFoundException | IOException e) {
             e.printStackTrace();
         }
-        return object;
+        return (T) object;
+    }
+
+    @Override
+    public T entryToObject(DatabaseEntry databaseEntry) {
+        return deserialize(databaseEntry.getData());
+    }
+
+    @Override
+    public void objectToEntry(T object, DatabaseEntry databaseEntry) {
+        databaseEntry.setData(serialize(object));
     }
 }

app/src/main/java/io/github/chronosx88/influence/helpers/StorageBerkeleyDB.kt

@@ -0,0 +1,262 @@
+package io.github.chronosx88.influence.helpers
+
+import com.sleepycat.collections.StoredSortedMap
+import com.sleepycat.je.Database
+import com.sleepycat.je.DatabaseConfig
+import com.sleepycat.je.Environment
+import com.sleepycat.je.EnvironmentConfig
+import net.tomp2p.connection.SignatureFactory
+import net.tomp2p.dht.Storage
+import net.tomp2p.peers.Number160
+import net.tomp2p.peers.Number320
+import net.tomp2p.peers.Number480
+import net.tomp2p.peers.Number640
+import net.tomp2p.storage.Data
+import java.io.File
+import java.security.PublicKey
+import java.util.*
+import java.util.concurrent.ConcurrentHashMap
+
+
+class StorageBerkeleyDB(peerId: Number160, path : File, signatureFactory: SignatureFactory) : Storage {
+    // Core
+    private val dataMap: StoredSortedMap<Number640, Data>
+    // Maintenance
+    private val timeoutMap: StoredSortedMap<Number640, Long>
+    private val timeoutMapRev: StoredSortedMap<Long, Set<Number640>>
+    // Protection
+    private val protectedDomainMap: StoredSortedMap<Number320, PublicKey>
+    private val protectedEntryMap: StoredSortedMap<Number480, PublicKey>
+    // Responsibility
+    private val responsibilityMap: StoredSortedMap<Number160, Number160>
+    private val responsibilityMapRev: StoredSortedMap<Number160, Set<Number160>>
+
+    private val dataMapDB: Database
+    private val timeoutMapDB: Database
+    private val timeoutMapRevDB: Database
+    private val protectedDomainMapDB: Database
+    private val protectedEntryMapDB: Database
+    private val responsibilityMapDB: Database
+    private val responsibilityMapRevDB: Database
+
+
+    private val storageCheckIntervalMillis: Int
+    private val dbEnvironment: Environment
+
+    init {
+        val envConfig = EnvironmentConfig()
+        envConfig.allowCreate = true
+        dbEnvironment = Environment(path, envConfig)
+        val dbConfig = DatabaseConfig()
+        dbConfig.allowCreate = true
+
+        dataMapDB = dbEnvironment.openDatabase(null, "dataMap_$peerId", dbConfig)
+        timeoutMapDB = dbEnvironment.openDatabase(null, "timeoutMap_$peerId", dbConfig)
+        timeoutMapRevDB = dbEnvironment.openDatabase(null, "timeoutMapRev_$peerId", dbConfig)
+        protectedDomainMapDB = dbEnvironment.openDatabase(null, "protectedDomainMap_$peerId", dbConfig)
+        protectedEntryMapDB = dbEnvironment.openDatabase(null, "protectedEntryMap_$peerId", dbConfig)
+        responsibilityMapDB = dbEnvironment.openDatabase(null, "responsibilityMap_$peerId", dbConfig)
+        responsibilityMapRevDB = dbEnvironment.openDatabase(null, "responsibilityMapRev_$peerId", dbConfig)
+
+        storageCheckIntervalMillis = 60 * 1000
+
+        dataMap = StoredSortedMap(dataMapDB, Serializer<Number640>(), DataSerializerEx(signatureFactory), true)
+        timeoutMap = StoredSortedMap(timeoutMapDB, Serializer<Number640>(), Serializer<Long>(), true)
+        timeoutMapRev = StoredSortedMap(timeoutMapRevDB, Serializer<Long>(), Serializer<Set<Number640>>(), true)
+        protectedDomainMap = StoredSortedMap(protectedDomainMapDB, Serializer<Number320>(), Serializer<PublicKey>(), true)
+        protectedEntryMap = StoredSortedMap(protectedEntryMapDB, Serializer<Number480>(), Serializer<PublicKey>(), true)
+        responsibilityMap = StoredSortedMap(responsibilityMapDB, Serializer<Number160>(), Serializer<Number160>(), true)
+        responsibilityMapRev = StoredSortedMap(responsibilityMapRevDB, Serializer<Number160>(), Serializer<Set<Number160>>(), true)
+    }
+
+    override fun contains(key: Number640?): Boolean {
+        return dataMap.containsKey(key)
+    }
+
+    override fun contains(from: Number640?, to: Number640?): Int {
+        return dataMap.subMap(from, true, to, true).size
+    }
+
+    override fun findContentForResponsiblePeerID(peerID: Number160?): MutableSet<Number160> {
+        return responsibilityMapRev[peerID] as MutableSet<Number160>
+    }
+
+    override fun findPeerIDsForResponsibleContent(locationKey: Number160?): Number160? {
+        return responsibilityMap[locationKey]
+    }
+
+    override fun put(key: Number640?, value: Data?): Data? {
+        return dataMap.put(key, value)
+    }
+
+    override fun get(key: Number640?): Data? {
+        return dataMap[key]
+    }
+
+    override fun remove(key: Number640?, returnData: Boolean): Data? {
+        return dataMap.remove(key)
+    }
+
+    override fun remove(from: Number640?, to: Number640?): NavigableMap<Number640, Data> {
+        val tmp = dataMap.subMap(from, true, to, true)
+        val retVal = TreeMap<Number640, Data>()
+        for(entry : Map.Entry<Number640, Data> in tmp.entries) {
+            retVal[entry.key] = entry.value
+        }
+        tmp.clear()
+        return retVal
+    }
+
+    override fun addTimeout(key: Number640, expiration: Long) {
+        val oldExpiration = timeoutMap.put(key, expiration)
+        putIfAbsent2(expiration, key)
+        if (oldExpiration == null) {
+            return
+        }
+        removeRevTimeout(key, oldExpiration)
+    }
+
+    private fun putIfAbsent2(expiration: Long, key: Number640) {
+        var timeouts = timeoutMapRev[expiration]
+        //var timeouts : MutableSet<Number640> = timeoutMapRev[expiration] as MutableSet<Number640>
+        if (timeouts == null) {
+            timeouts = Collections.newSetFromMap(ConcurrentHashMap())
+        }
+        (timeouts as MutableSet).add(key)
+        timeoutMapRev[expiration] = timeouts
+    }
+
+    private fun removeRevTimeout(key: Number640, expiration: Long?) {
+        val tmp = timeoutMapRev[expiration] as MutableSet<Number640>
+        if (tmp != null) {
+            tmp.remove(key)
+            if (tmp.isEmpty()) {
+                timeoutMapRev.remove(expiration)
+            } else {
+                timeoutMapRev[expiration!!] = tmp
+            }
+        }
+    }
+
+    override fun updateResponsibilities(locationKey: Number160, peerId: Number160?): Boolean {
+        val oldPeerID = responsibilityMap.put(locationKey, peerId)
+        val hasChanged: Boolean
+        if (oldPeerID != null) {
+            if (oldPeerID == peerId) {
+                hasChanged = false
+            } else {
+                removeRevResponsibility(oldPeerID, locationKey)
+                hasChanged = true
+            }
+        } else {
+            hasChanged = true
+        }
+        var contentIDs: MutableSet<Number160>? = responsibilityMapRev[peerId] as MutableSet
+        if (contentIDs == null) {
+            contentIDs = HashSet()
+        }
+        contentIDs.add(locationKey)
+        responsibilityMapRev[peerId] = contentIDs
+        return hasChanged
+    }
+
+    private fun removeRevResponsibility(peerId: Number160, locationKey: Number160) {
+        val contentIDs = responsibilityMapRev[peerId] as MutableSet
+        if (contentIDs != null) {
+            contentIDs.remove(locationKey)
+            if (contentIDs.isEmpty()) {
+                responsibilityMapRev.remove(peerId)
+            } else {
+                responsibilityMapRev[peerId] = contentIDs
+            }
+        }
+    }
+
+    override fun protectDomain(key: Number320?, publicKey: PublicKey?): Boolean {
+        protectedDomainMap[key] = publicKey
+        return true
+    }
+
+    override fun storageCheckIntervalMillis(): Int {
+        return storageCheckIntervalMillis
+    }
+
+    override fun isDomainProtectedByOthers(key: Number320?, publicKey: PublicKey?): Boolean {
+        val other = protectedDomainMap[key] ?: return false
+        return other != publicKey
+    }
+
+    override fun removeTimeout(key: Number640) {
+        val expiration = timeoutMap.remove(key) ?: return
+        removeRevTimeout(key, expiration)
+    }
+
+    override fun removeResponsibility(locationKey: Number160) {
+        val peerId = responsibilityMap.remove(locationKey)
+        if (peerId != null) {
+            removeRevResponsibility(peerId, locationKey)
+        }
+    }
+
+    override fun protectEntry(key: Number480?, publicKey: PublicKey?): Boolean {
+        protectedEntryMap[key] = publicKey
+        return true
+    }
+
+    override fun map(): NavigableMap<Number640, Data> {
+        val retVal = TreeMap<Number640, Data>()
+        for ((key, value) in dataMap) {
+            retVal[key] = value
+        }
+
+        return retVal
+    }
+
+    override fun isEntryProtectedByOthers(key: Number480?, publicKey: PublicKey?): Boolean {
+        val other = protectedEntryMap[key] ?: return false
+        return other != publicKey
+    }
+
+    override fun subMap(from: Number640?, to: Number640?, limit: Int, ascending: Boolean): NavigableMap<Number640, Data> {
+        val tmp = dataMap.subMap(from, true, to, true)
+        val descendingMap = TreeMap<Number640, Data>(tmp).descendingMap()
+        val retVal = TreeMap<Number640, Data>()
+        if (limit < 0) {
+            for ((key, value) in if (ascending) tmp else descendingMap) {
+                retVal[key] = value
+            }
+        } else {
+            val limit1 = Math.min(limit, tmp.size)
+            val iterator = if (ascending)
+                tmp.entries.iterator()
+            else
+                descendingMap.entries.iterator()
+            var i = 0
+            while (iterator.hasNext() && i < limit1) {
+                val entry = iterator.next()
+                retVal[entry.key] = entry.value
+                i++
+            }
+        }
+        return retVal
+    }
+
+    override fun subMapTimeout(to: Long): MutableCollection<Number640> {
+        val tmp = timeoutMapRev.subMap(0L, to)
+        val toRemove = ArrayList<Number640>()
+        for (set in tmp.values) {
+            toRemove.addAll(set)
+        }
+        return toRemove
+    }
+
+    override fun close() {
+        dataMapDB.close()
+        timeoutMapDB.close()
+        timeoutMapRevDB.close()
+        protectedDomainMapDB.close()
+        protectedEntryMapDB.close()
+        responsibilityMapDB.close()
+        responsibilityMapRevDB.close()
+    }
+}

app/src/main/java/io/github/chronosx88/influence/helpers/StorageMVStore.java

@@ -1,5 +1,5 @@
 package io.github.chronosx88.influence.helpers;
-
+/*
 import android.util.Log;
 
 import net.tomp2p.connection.DSASignatureFactory;
@@ -391,3 +391,4 @@ public class StorageMVStore implements Storage {
         return data;
     }
 }
+*/

app/src/main/java/io/github/chronosx88/influence/helpers/StorageMapDB.java

@@ -1,5 +1,5 @@
 package io.github.chronosx88.influence.helpers;
-
+/*
 import net.tomp2p.connection.SignatureFactory;
 import net.tomp2p.dht.Storage;
 import net.tomp2p.peers.Number160;
@@ -96,27 +96,6 @@ public class StorageMapDB implements Storage {
     @Override
     public NavigableMap<Number640, Data> remove(Number640 from, Number640 to) {
         NavigableMap<Number640, Data> tmp = dataMap.subMap(from, true, to, true);
-
-        // new TreeMap<Number640, Data>(tmp); is not possible as this may lead to no such element exception:
-        //
-        //      java.util.NoSuchElementException: null
-        //    	at java.util.concurrent.ConcurrentSkipListMap$SubMap$SubMapIter.advance(ConcurrentSkipListMap.java:3030) ~[na:1.7.0_60]
-        //    	at java.util.concurrent.ConcurrentSkipListMap$SubMap$SubMapEntryIterator.next(ConcurrentSkipListMap.java:3100) ~[na:1.7.0_60]
-        //    	at java.util.concurrent.ConcurrentSkipListMap$SubMap$SubMapEntryIterator.next(ConcurrentSkipListMap.java:3096) ~[na:1.7.0_60]
-        //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2394) ~[na:1.7.0_60]
-        //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2418) ~[na:1.7.0_60]
-        //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2418) ~[na:1.7.0_60]
-        //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2418) ~[na:1.7.0_60]
-        //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2418) ~[na:1.7.0_60]
-        //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2418) ~[na:1.7.0_60]
-        //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2418) ~[na:1.7.0_60]
-        //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2418) ~[na:1.7.0_60]
-        //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2344) ~[na:1.7.0_60]
-        //    	at java.util.TreeMap.<init>(TreeMap.java:195) ~[na:1.7.0_60]
-        //    	at net.tomp2p.dht.StorageMemory.subMap(StorageMemory.java:119) ~[classes/:na]
-        //
-        // the reason is that the size in TreeMap.buildFromSorted is stored beforehand, then iteratated. If the size changes,
-        // then you will call next() that returns null and an exception is thrown.
         final NavigableMap<Number640, Data> retVal = new TreeMap<Number640, Data>();
         for(final Map.Entry<Number640, Data> entry:tmp.entrySet()) {
             retVal.put(entry.getKey(), entry.getValue());
@@ -132,28 +111,6 @@ public class StorageMapDB implements Storage {
         NavigableMap<Number640, Data> tmp = dataMap.subMap(from, true, to, true);
         final NavigableMap<Number640, Data> retVal = new TreeMap<Number640, Data>();
         if (limit < 0) {
-
-            // new TreeMap<Number640, Data>(tmp); is not possible as this may lead to no such element exception:
-            //
-            //      java.util.NoSuchElementException: null
-            //    	at java.util.concurrent.ConcurrentSkipListMap$SubMap$SubMapIter.advance(ConcurrentSkipListMap.java:3030) ~[na:1.7.0_60]
-            //    	at java.util.concurrent.ConcurrentSkipListMap$SubMap$SubMapEntryIterator.next(ConcurrentSkipListMap.java:3100) ~[na:1.7.0_60]
-            //    	at java.util.concurrent.ConcurrentSkipListMap$SubMap$SubMapEntryIterator.next(ConcurrentSkipListMap.java:3096) ~[na:1.7.0_60]
-            //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2394) ~[na:1.7.0_60]
-            //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2418) ~[na:1.7.0_60]
-            //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2418) ~[na:1.7.0_60]
-            //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2418) ~[na:1.7.0_60]
-            //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2418) ~[na:1.7.0_60]
-            //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2418) ~[na:1.7.0_60]
-            //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2418) ~[na:1.7.0_60]
-            //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2418) ~[na:1.7.0_60]
-            //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2344) ~[na:1.7.0_60]
-            //    	at java.util.TreeMap.<init>(TreeMap.java:195) ~[na:1.7.0_60]
-            //    	at net.tomp2p.dht.StorageMemory.subMap(StorageMemory.java:119) ~[classes/:na]
-            //
-            // the reason is that the size in TreeMap.buildFromSorted is stored beforehand, then iteratated. If the size changes,
-            // then you will call next() that returns null and an exception is thrown.
-
             for(final Map.Entry<Number640, Data> entry:(ascending ? tmp : tmp.descendingMap()).entrySet()) {
                 retVal.put(entry.getKey(), entry.getValue());
             }
@@ -171,27 +128,6 @@ public class StorageMapDB implements Storage {
 
     @Override
     public NavigableMap<Number640, Data> map() {
-
-        // new TreeMap<Number640, Data>(dataMap); is not possible as this may lead to no such element exception:
-        //
-        //      java.util.NoSuchElementException: null
-        //    	at java.util.concurrent.ConcurrentSkipListMap$SubMap$SubMapIter.advance(ConcurrentSkipListMap.java:3030) ~[na:1.7.0_60]
-        //    	at java.util.concurrent.ConcurrentSkipListMap$SubMap$SubMapEntryIterator.next(ConcurrentSkipListMap.java:3100) ~[na:1.7.0_60]
-        //    	at java.util.concurrent.ConcurrentSkipListMap$SubMap$SubMapEntryIterator.next(ConcurrentSkipListMap.java:3096) ~[na:1.7.0_60]
-        //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2394) ~[na:1.7.0_60]
-        //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2418) ~[na:1.7.0_60]
-        //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2418) ~[na:1.7.0_60]
-        //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2418) ~[na:1.7.0_60]
-        //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2418) ~[na:1.7.0_60]
-        //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2418) ~[na:1.7.0_60]
-        //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2418) ~[na:1.7.0_60]
-        //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2418) ~[na:1.7.0_60]
-        //    	at java.util.TreeMap.buildFromSorted(TreeMap.java:2344) ~[na:1.7.0_60]
-        //    	at java.util.TreeMap.<init>(TreeMap.java:195) ~[na:1.7.0_60]
-        //    	at net.tomp2p.dht.StorageMemory.subMap(StorageMemory.java:119) ~[classes/:na]
-        //
-        // the reason is that the size in TreeMap.buildFromSorted is stored beforehand, then iteratated. If the size changes,
-        // then you will call next() that returns null and an exception is thrown.
         final NavigableMap<Number640, Data> retVal = new TreeMap<Number640, Data>();
         for(final Map.Entry<Number640, Data> entry:dataMap.entrySet()) {
             retVal.put(entry.getKey(), entry.getValue());
@@ -354,3 +290,4 @@ public class StorageMapDB implements Storage {
         return storageCheckIntervalMillis;
     }
 }
+*/

app/src/main/java/io/github/chronosx88/influence/logic/ChatLogic.java

@@ -148,8 +148,8 @@ public class ChatLogic implements IChatLogicContract {
                 if(messages.size() > 10) {
                     String messageID = UUID.randomUUID().toString();
                     try {
-                        chatEntity.chunkCursor += 1;
+                        P2PUtils.put(chatEntity.chatID + "_messages" + chunkID, messageID, new Data(gson.toJson(new NextChunkReference(messageID, AppHelper.getPeerID(), AppHelper.getPeerID(), System.currentTimeMillis(), chatEntity.chunkCursor+1))));
-                        P2PUtils.put(chatID + "_messages" + chatEntity.chunkCursor, messageID, new Data(gson.toJson(new NextChunkReference(messageID, AppHelper.getPeerID(), AppHelper.getPeerID(), System.currentTimeMillis(), chatEntity.chunkCursor))));
+                        P2PUtils.put(chatEntity.chatID + "_newMessage", null, new Data(messageID));
                         LocalDBWrapper.updateChatEntity(chatEntity);
                     } catch (IOException e) {
                         e.printStackTrace();

app/src/main/java/io/github/chronosx88/influence/logic/MainLogic.java

@@ -10,7 +10,6 @@ import com.google.gson.JsonObject;
 import net.tomp2p.connection.DSASignatureFactory;
 import net.tomp2p.dht.PeerBuilderDHT;
 import net.tomp2p.dht.PeerDHT;
-import net.tomp2p.dht.StorageMemory;
 import net.tomp2p.futures.FutureBootstrap;
 import net.tomp2p.futures.FutureDiscover;
 import net.tomp2p.nat.FutureRelayNAT;
@@ -43,7 +42,7 @@ import io.github.chronosx88.influence.helpers.JVMShutdownHook;
 import io.github.chronosx88.influence.helpers.KeyPairManager;
 import io.github.chronosx88.influence.helpers.NetworkHandler;
 import io.github.chronosx88.influence.helpers.P2PUtils;
-import io.github.chronosx88.influence.helpers.StorageMapDB;
+import io.github.chronosx88.influence.helpers.StorageBerkeleyDB;
 import io.github.chronosx88.influence.helpers.actions.UIActions;
 import io.github.chronosx88.influence.models.PublicUserProfile;
 
@@ -60,6 +59,7 @@ public class MainLogic implements IMainLogicContract {
     private AutoReplication replication;
     private KeyPairManager keyPairManager;
     private Thread checkNewChatsThread = null;
+    private StorageBerkeleyDB storage;
 
     public MainLogic() {
         this.context = AppHelper.getContext();
@@ -83,15 +83,16 @@ public class MainLogic implements IMainLogicContract {
 
         new Thread(() -> {
             try {
-                StorageMapDB storageMapDB = new StorageMapDB(peerID, context.getFilesDir(), new DSASignatureFactory());
+                StorageBerkeleyDB storageBerkeleyDB = new StorageBerkeleyDB(peerID, context.getFilesDir(), new DSASignatureFactory());
+                this.storage = storageBerkeleyDB;
                 peerDHT = new PeerBuilderDHT(
                         new PeerBuilder(peerID)
                                 .ports(7243)
                                 .start()
                 )
-                        .storage(storageMapDB)
+                        .storage(storageBerkeleyDB)
                         .start();
-                Runtime.getRuntime().addShutdownHook(new JVMShutdownHook(storageMapDB));
+                Runtime.getRuntime().addShutdownHook(new JVMShutdownHook(storageBerkeleyDB));
                 try {
                     String bootstrapIP = this.preferences.getString("bootstrapAddress", null);
                     if(bootstrapIP == null) {
@@ -227,7 +228,8 @@ public class MainLogic implements IMainLogicContract {
                 replication.shutdown().start();
             }
             peerDHT.peer().announceShutdown().start().awaitUninterruptibly();
-            peerDHT.peer().shutdown();
+            peerDHT.peer().shutdown().awaitUninterruptibly();
+            storage.close();
         }).start();
     }
 

build.gradle

@@ -1,6 +1,7 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 
 buildscript {
+    ext.kotlin_version = '1.3.21'
     repositories {
         google()
         jcenter()
@@ -10,7 +11,8 @@ buildscript {
     }
     dependencies {
         classpath 'com.android.tools.build:gradle:3.3.2'
-        
+        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files
     }