From 39cc3511ad2253e330f6ce243e3915a4897aa3d9 Mon Sep 17 00:00:00 2001
From: maibin <michal.aibin@gmail.com>
Date: Mon, 19 Dec 2016 19:13:52 +0100
Subject: [PATCH] Simulated Annnealing fixes (#907)

* @Async and Spring Security

* @Async with SecurityContext propagated

* Spring and @Async

* Simulated Annealing algorithm

* Simulated Annealing algorithm

* Rebase

* Rebase
---
 core-java/README.md                           |  1 +
 .../java/com/baeldung/algorithms/City.java    | 22 +++++++++----------
 .../algorithms/SimulatedAnnealing.java        |  4 +++-
 .../java/com/baeldung/algorithms/Travel.java  |  5 ++++-
 4 files changed, 19 insertions(+), 13 deletions(-)

diff --git a/core-java/README.md b/core-java/README.md
index ec475c1167..3abe1ba808 100644
--- a/core-java/README.md
+++ b/core-java/README.md
@@ -45,3 +45,4 @@
 - [Getting Started with Java Properties](http://www.baeldung.com/java-properties)
 - [Grep in Java](http://www.baeldung.com/grep-in-java)
 - [Java - Combine Multiple Collections](http://www.baeldung.com/java-combine-multiple-collections)
+- [Simulated Annealing for Travelling Salesman Problem](http://www.baeldung.com/java-simulated-annealing-for-traveling-salesman)
diff --git a/core-java/src/main/java/com/baeldung/algorithms/City.java b/core-java/src/main/java/com/baeldung/algorithms/City.java
index 32335cda80..1a96dc759d 100644
--- a/core-java/src/main/java/com/baeldung/algorithms/City.java
+++ b/core-java/src/main/java/com/baeldung/algorithms/City.java
@@ -5,18 +5,18 @@ import lombok.Data;
 @Data
 public class City {
 
-    private int x;
-    private int y;
+	private int x;
+	private int y;
 
-    public City() {
-        this.x = (int) (Math.random() * 500);
-        this.y = (int) (Math.random() * 500);
-    }
+	public City() {
+		this.x = (int) (Math.random() * 500);
+		this.y = (int) (Math.random() * 500);
+	}
 
-    public double distanceToCity(City city) {
-        int x = Math.abs(getX() - city.getX());
-        int y = Math.abs(getY() - city.getY());
-        return Math.sqrt(Math.pow(x, 2) + Math.pow(y, 2));
-    }
+	public double distanceToCity(City city) {
+		int x = Math.abs(getX() - city.getX());
+		int y = Math.abs(getY() - city.getY());
+		return Math.sqrt(Math.pow(x, 2) + Math.pow(y, 2));
+	}
 
 }
diff --git a/core-java/src/main/java/com/baeldung/algorithms/SimulatedAnnealing.java b/core-java/src/main/java/com/baeldung/algorithms/SimulatedAnnealing.java
index 3ccba9b3e9..cf1dad098e 100644
--- a/core-java/src/main/java/com/baeldung/algorithms/SimulatedAnnealing.java
+++ b/core-java/src/main/java/com/baeldung/algorithms/SimulatedAnnealing.java
@@ -25,6 +25,8 @@ public class SimulatedAnnealing {
                     currentSolution.revertSwap();
                 }
                 t *= coolingRate;
+            } else {
+            	continue;
             }
             if (i % 100 == 0) {
                 System.out.println("Iteration #" + i);
@@ -34,7 +36,7 @@ public class SimulatedAnnealing {
     }
 
     public static void main(String[] args) {
-        System.out.println("Optimized distance for travel: " + simulateAnnealing(10, 10000, 0.9));
+        System.out.println("Optimized distance for travel: " + simulateAnnealing(10, 10000, 0.9995));
     }
 
 }
diff --git a/core-java/src/main/java/com/baeldung/algorithms/Travel.java b/core-java/src/main/java/com/baeldung/algorithms/Travel.java
index 6e6059b3eb..af03b0abbb 100644
--- a/core-java/src/main/java/com/baeldung/algorithms/Travel.java
+++ b/core-java/src/main/java/com/baeldung/algorithms/Travel.java
@@ -27,7 +27,10 @@ public class Travel {
         int a = generateRandomIndex();
         int b = generateRandomIndex();
         previousTravel = travel;
-        travel.set(a, travel.get(b));
+        City x = travel.get(a);
+        City y = travel.get(b);
+        travel.set(a, y);
+        travel.set(b, x);
     }
 
     public void revertSwap() {