diff --git a/hawkbit-repository/src/main/java/org/eclipse/hawkbit/repository/model/DistributionSetMetadata.java b/hawkbit-repository/src/main/java/org/eclipse/hawkbit/repository/model/DistributionSetMetadata.java
index 28afd5517..67a99506c 100644
--- a/hawkbit-repository/src/main/java/org/eclipse/hawkbit/repository/model/DistributionSetMetadata.java
+++ b/hawkbit-repository/src/main/java/org/eclipse/hawkbit/repository/model/DistributionSetMetadata.java
@@ -34,16 +34,9 @@ public class DistributionSetMetadata extends MetaData {
     private DistributionSet distributionSet;
 
     public DistributionSetMetadata() {
-        super();
+        // default public constructor for JPA
     }
 
-    /**
-     * Parameter constructor.
-     *
-     * @param key
-     * @param distributionSet
-     * @param value
-     */
     public DistributionSetMetadata(final String key, final DistributionSet distributionSet, final String value) {
         super(key, value);
         this.distributionSet = distributionSet;
@@ -71,15 +64,9 @@ public class DistributionSetMetadata extends MetaData {
 
     @Override
     public boolean equals(final Object obj) {
-        if (this == obj) {
-            return true;
-        }
         if (!super.equals(obj)) {
             return false;
         }
-        if (!(obj instanceof DistributionSetMetadata)) {
-            return false;
-        }
         final DistributionSetMetadata other = (DistributionSetMetadata) obj;
         if (distributionSet == null) {
             if (other.distributionSet != null) {
diff --git a/hawkbit-repository/src/main/java/org/eclipse/hawkbit/repository/model/MetaData.java b/hawkbit-repository/src/main/java/org/eclipse/hawkbit/repository/model/MetaData.java
index 97ffacdcc..c41a0e8c9 100644
--- a/hawkbit-repository/src/main/java/org/eclipse/hawkbit/repository/model/MetaData.java
+++ b/hawkbit-repository/src/main/java/org/eclipse/hawkbit/repository/model/MetaData.java
@@ -74,7 +74,7 @@ public abstract class MetaData implements Serializable {
         if (obj == null) {
             return false;
         }
-        if (!(obj instanceof MetaData)) {
+        if (!(this.getClass().isInstance(obj))) {
             return false;
         }
         final MetaData other = (MetaData) obj;
diff --git a/hawkbit-repository/src/main/java/org/eclipse/hawkbit/repository/model/SoftwareModuleMetadata.java b/hawkbit-repository/src/main/java/org/eclipse/hawkbit/repository/model/SoftwareModuleMetadata.java
index 8783fec96..5ddd273d3 100644
--- a/hawkbit-repository/src/main/java/org/eclipse/hawkbit/repository/model/SoftwareModuleMetadata.java
+++ b/hawkbit-repository/src/main/java/org/eclipse/hawkbit/repository/model/SoftwareModuleMetadata.java
@@ -33,22 +33,10 @@ public class SoftwareModuleMetadata extends MetaData {
     @JoinColumn(name = "sw_id", foreignKey = @ForeignKey(value = ConstraintMode.CONSTRAINT, name = "fk_metadata_sw"))
     private SoftwareModule softwareModule;
 
-    /**
-     * Default constructor for JPA.
-     */
     public SoftwareModuleMetadata() {
-        super();
+        // default public constructor for JPA
     }
 
-    /**
-     * Standard constructor.
-     *
-     * @param key
-     *            of the meta data element
-     * @param softwareModule
-     * @param value
-     *            of the meta data element
-     */
     public SoftwareModuleMetadata(final String key, final SoftwareModule softwareModule, final String value) {
         super(key, value);
         this.softwareModule = softwareModule;
@@ -76,15 +64,9 @@ public class SoftwareModuleMetadata extends MetaData {
 
     @Override
     public boolean equals(final Object obj) {
-        if (this == obj) {
-            return true;
-        }
         if (!super.equals(obj)) {
             return false;
         }
-        if (!(obj instanceof SoftwareModuleMetadata)) {
-            return false;
-        }
         final SoftwareModuleMetadata other = (SoftwareModuleMetadata) obj;
         if (softwareModule == null) {
             if (other.softwareModule != null) {