From 5b458eff274dd7f94969a4cdedf58c078ceff530 Mon Sep 17 00:00:00 2001
From: ChronosX88 <chronosx88@gmail.com>
Date: Wed, 24 Apr 2019 12:42:54 +0400
Subject: [PATCH] Added getDistance() method to Number160. Added .gradle to
 .gitignore

---
 .gitignore                                    |  3 +-
 .../influencedht/core/Number160.java          | 52 ++-----------------
 .../core/routing/KademliaRoutingTable.kt      | 14 ++---
 3 files changed, 13 insertions(+), 56 deletions(-)

diff --git a/.gitignore b/.gitignore
index d4f654f..751c924 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
 /.idea
 /build
-/out
\ No newline at end of file
+/out
+/.gradle
\ No newline at end of file
diff --git a/src/main/java/io/gitub/chronosx88/influencedht/core/Number160.java b/src/main/java/io/gitub/chronosx88/influencedht/core/Number160.java
index 0f1c4ee..dce342d 100644
--- a/src/main/java/io/gitub/chronosx88/influencedht/core/Number160.java
+++ b/src/main/java/io/gitub/chronosx88/influencedht/core/Number160.java
@@ -475,60 +475,16 @@ public final class Number160 extends Number implements Comparable<Number160> {
         return Utils.makeSHAHash(string);
     }
 
-    /**
-     * Counts the number of leading 0's in this NodeId
-     *
-     * @return Integer The number of leading 0's
-     */
-    public int getFirstSetBitIndex()
-    {
-        int prefixLength = 0;
-
-        for (byte b : this.toByteArray())
-        {
-            if (b == 0)
-            {
-                prefixLength += 8;
-            }
-            else
-            {
-                /* If the byte is not 0, we need to count how many MSBs are 0 */
-                int count = 0;
-                for (int i = 7; i >= 0; i--)
-                {
-                    boolean a = (b & (1 << i)) == 0;
-                    if (a)
-                    {
-                        count++;
-                    }
-                    else
-                    {
-                        break;   // Reset the count if we encounter a non-zero number
-                    }
-                }
-
-                /* Add the count of MSB 0s to the prefix length */
-                prefixLength += count;
-
-                /* Break here since we've now covered the MSB 0s */
-                break;
-            }
-        }
-        return prefixLength;
-    }
-
     /**
      * Gets the distance from this ID to another ID
      *
-     * @param to
+     * @param to Another ID
      *
-     * @return Integer The distance
+     * @return The distance
      */
     public int getDistance(Number160 to)
     {
-         // Compute the xor of this and to
-         // Get the index i of the first set bit of the xor returned NodeId
-         // The distance between them is ID_LENGTH - i
-        return BITS - this.xor(to).getFirstSetBitIndex();
+         // Compute the xor of this and get bit length
+        return this.xor(to).bitLength();
     }
 }
diff --git a/src/main/kotlin/io/github/chronosx88/influencedht/core/routing/KademliaRoutingTable.kt b/src/main/kotlin/io/github/chronosx88/influencedht/core/routing/KademliaRoutingTable.kt
index c91c3ff..ee31abf 100644
--- a/src/main/kotlin/io/github/chronosx88/influencedht/core/routing/KademliaRoutingTable.kt
+++ b/src/main/kotlin/io/github/chronosx88/influencedht/core/routing/KademliaRoutingTable.kt
@@ -33,7 +33,7 @@ class KademliaRoutingTable(
         @Synchronized get() {
             val nodes = ArrayList<PeerAddress>()
 
-            for (b in this.buckets!!) {
+            for (b in this.buckets) {
                 for (c in b.getContacts()) {
                     nodes.add(c.getPeerAddress())
                 }
@@ -49,7 +49,7 @@ class KademliaRoutingTable(
         get() {
             val contacts = ArrayList<PeerContact>()
 
-            for (b in this.buckets!!) {
+            for (b in this.buckets) {
                 contacts.addAll(b.getContacts())
             }
 
@@ -86,7 +86,7 @@ class KademliaRoutingTable(
      */
     @Synchronized
     fun insert(c: PeerContact) {
-        this.buckets!![this.getBucketId(c.getPeerAddress().nodeId)].insert(c)
+        this.buckets[this.getBucketId(c.getPeerAddress().nodeId)].insert(c)
     }
 
     /**
@@ -96,7 +96,7 @@ class KademliaRoutingTable(
      */
     @Synchronized
     fun insert(n: PeerAddress) {
-        this.buckets!![this.getBucketId(n.nodeId)].insert(n)
+        this.buckets[this.getBucketId(n.nodeId)].insert(n)
     }
 
     /**
@@ -107,7 +107,7 @@ class KademliaRoutingTable(
      * @return Integer The bucket ID in which the given node should be placed.
      */
     fun getBucketId(nid: Number160?): Int {
-        val bId = this.localNode.nodeId!!.xor(nid).bitLength() - 1
+        val bId = this.localNode.nodeId!!.getDistance(nid) - 1
 
         /* If we are trying to insert a node into it's own routing table, then the bucket ID will be -1, so let's just keep it in bucket 0 */
         return if (bId < 0) 0 else bId
@@ -163,14 +163,14 @@ class KademliaRoutingTable(
         val bucketId = this.getBucketId(n.nodeId)
 
         /* Remove the contact from the bucket */
-        this.buckets!![bucketId].removeNode(n)
+        this.buckets[bucketId].removeNode(n)
     }
 
     @Synchronized
     override fun toString(): String {
         val sb = StringBuilder("\n ***************** \n")
         var totalContacts = 0
-        for (b in this.buckets!!) {
+        for (b in this.buckets) {
             if (b.numContacts() > 0) {
                 totalContacts += b.numContacts()
                 sb.append("# nodes in Bucket with depth ")