diff --git a/spring-security-mvc-ldap/src/main/java/org/baeldung/controller/MyController.java b/spring-security-mvc-ldap/src/main/java/org/baeldung/controller/MyController.java
index 08a274a956..a3fbb129cb 100644
--- a/spring-security-mvc-ldap/src/main/java/org/baeldung/controller/MyController.java
+++ b/spring-security-mvc-ldap/src/main/java/org/baeldung/controller/MyController.java
@@ -7,7 +7,7 @@ import java.util.HashSet;
 import java.util.Map;
 import java.util.Set;
 
-import org.baeldung.metric.MetricService;
+import org.baeldung.metric.IMetricService;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.security.core.Authentication;
 import org.springframework.security.core.GrantedAuthority;
@@ -24,7 +24,7 @@ import org.springframework.web.bind.annotation.ResponseBody;
 public class MyController {
 
     @Autowired
-    private MetricService metricService;
+    private IMetricService metricService;
 
     @RequestMapping("/")
     public String init(Map<String, Object> model, Principal principal) {
diff --git a/spring-security-mvc-ldap/src/main/java/org/baeldung/metric/IMetricService.java b/spring-security-mvc-ldap/src/main/java/org/baeldung/metric/IMetricService.java
new file mode 100644
index 0000000000..6814573138
--- /dev/null
+++ b/spring-security-mvc-ldap/src/main/java/org/baeldung/metric/IMetricService.java
@@ -0,0 +1,8 @@
+package org.baeldung.metric;
+
+public interface IMetricService {
+
+    void increaseCount(final int status);
+
+    Object[][] getGraphData();
+}
diff --git a/spring-security-mvc-ldap/src/main/java/org/baeldung/metric/MetricFilter.java b/spring-security-mvc-ldap/src/main/java/org/baeldung/metric/MetricFilter.java
index 2c76001889..4c00fda530 100644
--- a/spring-security-mvc-ldap/src/main/java/org/baeldung/metric/MetricFilter.java
+++ b/spring-security-mvc-ldap/src/main/java/org/baeldung/metric/MetricFilter.java
@@ -15,7 +15,7 @@ import org.springframework.stereotype.Component;
 public class MetricFilter implements Filter {
 
     @Autowired
-    private MetricService metricService;
+    private IMetricService metricService;
 
     @Override
     public void init(final FilterConfig config) throws ServletException {
diff --git a/spring-security-mvc-ldap/src/main/java/org/baeldung/metric/MetricService.java b/spring-security-mvc-ldap/src/main/java/org/baeldung/metric/MetricService.java
index 9b1e100ce1..73c9f538e7 100644
--- a/spring-security-mvc-ldap/src/main/java/org/baeldung/metric/MetricService.java
+++ b/spring-security-mvc-ldap/src/main/java/org/baeldung/metric/MetricService.java
@@ -13,7 +13,7 @@ import org.springframework.scheduling.annotation.Scheduled;
 import org.springframework.stereotype.Service;
 
 @Service
-public class MetricService {
+public class MetricService implements IMetricService {
 
     @Autowired
     private MetricRepository repo;
@@ -21,9 +21,8 @@ public class MetricService {
     @Autowired
     private CounterService counter;
 
-    private ArrayList<ArrayList<Integer>> statusMetric;
+    private List<ArrayList<Integer>> statusMetric;
     private List<String> statusList;
-
     private static final SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm");
 
     public MetricService() {
@@ -32,6 +31,8 @@ public class MetricService {
         statusList = new ArrayList<String>();
     }
 
+    // API
+
     public void increaseCount(final int status) {
         counter.increment("status." + status);
         if (!statusList.contains("counter.status." + status)) {
@@ -39,6 +40,36 @@ public class MetricService {
         }
     }
 
+    public Object[][] getGraphData() {
+        Date current = new Date();
+        int colCount = statusList.size() + 1;
+        int rowCount = statusMetric.size() + 1;
+        Object[][] result = new Object[rowCount][colCount];
+        result[0][0] = "Time";
+
+        int j = 1;
+        for (final String status : statusList) {
+            result[0][j] = status;
+            j++;
+        }
+
+        List<Integer> temp;
+        for (int i = 1; i < rowCount; i++) {
+            temp = statusMetric.get(i - 1);
+            result[i][0] = dateFormat.format(new Date(current.getTime() - (60000 * (rowCount - i))));
+            for (j = 1; j <= temp.size(); j++) {
+                result[i][j] = temp.get(j - 1);
+            }
+            while (j < colCount) {
+                result[i][j] = 0;
+                j++;
+            }
+        }
+        return result;
+    }
+
+    // Non - API
+
     @Scheduled(fixedDelay = 60000)
     private void exportMetrics() {
         Metric<?> metric;
@@ -55,35 +86,4 @@ public class MetricService {
         }
         statusMetric.add(statusCount);
     }
-
-    public Object[][] getGraphData() {
-        Date current = new Date();
-        int colCount = statusList.size() + 1;
-        int rowCount = statusMetric.size() + 1;
-
-        Object[][] result = new Object[rowCount][colCount];
-        result[0][0] = "Time";
-
-        int j = 1;
-        for (final String status : statusList) {
-            result[0][j] = status;
-            j++;
-        }
-
-        ArrayList<Integer> temp;
-        for (int i = 1; i < rowCount; i++) {
-            temp = statusMetric.get(i - 1);
-            result[i][0] = dateFormat.format(new Date(current.getTime() - (60000 * (rowCount - i))));
-            for (j = 1; j <= temp.size(); j++) {
-                result[i][j] = temp.get(j - 1);
-            }
-            while (j < colCount) {
-                result[i][j] = 0;
-                j++;
-            }
-        }
-
-        return result;
-    }
-
 }
diff --git a/spring-security-rest-full/src/main/java/org/baeldung/web/controller/RootController.java b/spring-security-rest-full/src/main/java/org/baeldung/web/controller/RootController.java
index a1364d0dae..6e4fd738aa 100644
--- a/spring-security-rest-full/src/main/java/org/baeldung/web/controller/RootController.java
+++ b/spring-security-rest-full/src/main/java/org/baeldung/web/controller/RootController.java
@@ -5,7 +5,7 @@ import java.net.URI;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
-import org.baeldung.web.metric.MetricService;
+import org.baeldung.web.metric.IMetricService;
 import org.baeldung.web.util.LinkUtil;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.HttpStatus;
@@ -20,7 +20,7 @@ import org.springframework.web.util.UriTemplate;
 public class RootController {
 
     @Autowired
-    private MetricService metricService;
+    private IMetricService metricService;
 
     public RootController() {
         super();
diff --git a/spring-security-rest-full/src/main/java/org/baeldung/web/metric/IMetricService.java b/spring-security-rest-full/src/main/java/org/baeldung/web/metric/IMetricService.java
new file mode 100644
index 0000000000..fe64366a45
--- /dev/null
+++ b/spring-security-rest-full/src/main/java/org/baeldung/web/metric/IMetricService.java
@@ -0,0 +1,12 @@
+package org.baeldung.web.metric;
+
+public interface IMetricService {
+
+    void increaseCount(final String request, final int status);
+
+    String getFullMetric();
+
+    String getStatusMetric();
+
+    Object[][] getGraphData();
+}
diff --git a/spring-security-rest-full/src/main/java/org/baeldung/web/metric/MetricService.java b/spring-security-rest-full/src/main/java/org/baeldung/web/metric/MetricService.java
index df633e492f..ed33b70ba3 100644
--- a/spring-security-rest-full/src/main/java/org/baeldung/web/metric/MetricService.java
+++ b/spring-security-rest-full/src/main/java/org/baeldung/web/metric/MetricService.java
@@ -10,7 +10,7 @@ import java.util.Set;
 import org.springframework.stereotype.Service;
 
 @Service
-public class MetricService {
+public class MetricService implements IMetricService {
 
     private Map<String, HashMap<Integer, Integer>> metricMap;
     private Map<Integer, Integer> statusMetric;
@@ -26,20 +26,24 @@ public class MetricService {
 
     // API
 
+    @Override
     public void increaseCount(final String request, final int status) {
         increaseMainMetric(request, status);
         increaseStatusMetric(status);
         updateTimeMap(status);
     }
 
+    @Override
     public String getFullMetric() {
         return metricMap.entrySet().toString();
     }
 
+    @Override
     public String getStatusMetric() {
         return statusMetric.entrySet().toString();
     }
 
+    @Override
     public Object[][] getGraphData() {
         final int colCount = statusMetric.keySet().size() + 1;
         final Set<Integer> allStatus = statusMetric.keySet();
@@ -54,7 +58,7 @@ public class MetricService {
             j++;
         }
         int i = 1;
-        HashMap<Integer, Integer> tempMap;
+        Map<Integer, Integer> tempMap;
         for (final Entry<String, HashMap<Integer, Integer>> entry : timeMap.entrySet()) {
             result[i][0] = entry.getKey();
             tempMap = entry.getValue();