diff --git a/src/main/java/com/labelzoom/api/model/components/AComponent.java b/src/main/java/com/labelzoom/api/model/components/AComponent.java
index b71ee34..6b2388f 100644
--- a/src/main/java/com/labelzoom/api/model/components/AComponent.java
+++ b/src/main/java/com/labelzoom/api/model/components/AComponent.java
@@ -41,7 +41,7 @@ public abstract class AComponent implements Cloneable {
     /**
      * Parameterless constructor
      */
-    public AComponent() { this(null); }
+    protected AComponent() { this(null); }
 
     /**
      * Cloning constructor
diff --git a/src/main/java/com/labelzoom/api/model/components/AContainer.java b/src/main/java/com/labelzoom/api/model/components/AContainer.java
index 2cdda68..eb5ce99 100644
--- a/src/main/java/com/labelzoom/api/model/components/AContainer.java
+++ b/src/main/java/com/labelzoom/api/model/components/AContainer.java
@@ -15,7 +15,6 @@
 import lombok.Getter;
 
 import java.util.ArrayList;
-import java.util.Arrays;
 import java.util.List;
 
 @Getter
@@ -26,7 +25,7 @@ public abstract class AContainer extends AComponent
     /**
      * Parameterless constructor
      */
-    public AContainer() { this(null); }
+    protected AContainer() { this(null); }
 
     /**
      * Cloning constructor
diff --git a/src/main/java/com/labelzoom/api/model/components/AFontComponent.java b/src/main/java/com/labelzoom/api/model/components/AFontComponent.java
index 4e480b3..b9fd757 100644
--- a/src/main/java/com/labelzoom/api/model/components/AFontComponent.java
+++ b/src/main/java/com/labelzoom/api/model/components/AFontComponent.java
@@ -29,7 +29,7 @@ public abstract class AFontComponent extends AComponent
     /**
      * Parameterless constructor
      */
-    public AFontComponent() { this(null); }
+    protected AFontComponent() { this(null); }
 
     /**
      * Cloning constructor
diff --git a/src/main/java/com/labelzoom/api/model/components/CLabel.java b/src/main/java/com/labelzoom/api/model/components/CLabel.java
index c1f1ebe..1ec2bef 100644
--- a/src/main/java/com/labelzoom/api/model/components/CLabel.java
+++ b/src/main/java/com/labelzoom/api/model/components/CLabel.java
@@ -130,10 +130,7 @@ private Map<String, CLayer> getLayerMap()
                 }
             }
         }
-        if (!layerMap.containsKey(DEFAULT_LAYER_NAME))
-        {
-            layerMap.put(DEFAULT_LAYER_NAME, new CLayer(DEFAULT_LAYER_NAME));
-        }
+        layerMap.computeIfAbsent(DEFAULT_LAYER_NAME, CLayer::new);
         return layerMap;
     }
 
diff --git a/src/main/java/com/labelzoom/api/model/components/IDynamicField.java b/src/main/java/com/labelzoom/api/model/components/IDynamicField.java
index ce65f00..f880939 100644
--- a/src/main/java/com/labelzoom/api/model/components/IDynamicField.java
+++ b/src/main/java/com/labelzoom/api/model/components/IDynamicField.java
@@ -4,9 +4,9 @@
 
 public interface IDynamicField extends Cloneable, IDataField
 {
-    Pattern SIMPLE_EXPRESSION_PATTERN = Pattern.compile("\"\\$\\{([A-Za-z0-9_]+)\\}\"");
-    Pattern VARIABLE_EXPRESSION_PATTERN = Pattern.compile("\\$\\{([A-Za-z0-9_]+)\\}");
-    Pattern VARIABLE_NAME_PATTERN = Pattern.compile("^([A-Za-z0-9_]+)$");
+    Pattern SIMPLE_EXPRESSION_PATTERN = Pattern.compile("\"\\$\\{(\\w+)\\}\"");
+    Pattern VARIABLE_EXPRESSION_PATTERN = Pattern.compile("\\$\\{(\\w+)\\}");
+    Pattern VARIABLE_NAME_PATTERN = Pattern.compile("^(\\w+)$");
 
     void setExpression(String expression);
     String getExpression();
diff --git a/src/main/java/com/labelzoom/api/model/components/barcodes/ABarcode.java b/src/main/java/com/labelzoom/api/model/components/barcodes/ABarcode.java
index 2b9d6f8..d3645fc 100644
--- a/src/main/java/com/labelzoom/api/model/components/barcodes/ABarcode.java
+++ b/src/main/java/com/labelzoom/api/model/components/barcodes/ABarcode.java
@@ -71,7 +71,7 @@ public enum BarcodeStyle
     /**
      * Parameterless constructor
      */
-    public ABarcode() { this(null, false); }
+    protected ABarcode() { this(null, false); }
 
     /**
      * Cloning constructor
diff --git a/src/main/java/com/labelzoom/api/model/components/barcodes/linear/ALinearBarcode.java b/src/main/java/com/labelzoom/api/model/components/barcodes/linear/ALinearBarcode.java
index 829ec3f..d3e7f55 100644
--- a/src/main/java/com/labelzoom/api/model/components/barcodes/linear/ALinearBarcode.java
+++ b/src/main/java/com/labelzoom/api/model/components/barcodes/linear/ALinearBarcode.java
@@ -40,7 +40,7 @@ public enum HumanReadableStyle
 	/**
 	 * Parameterless constructor
 	 */
-	public ALinearBarcode() { this(null, false); }
+	protected ALinearBarcode() { this(null, false); }
 
 	/**
 	 * Cloning constructor
diff --git a/src/main/java/com/labelzoom/api/model/components/barcodes/twod/A2DBarcode.java b/src/main/java/com/labelzoom/api/model/components/barcodes/twod/A2DBarcode.java
index c9a5a86..a6ce53c 100644
--- a/src/main/java/com/labelzoom/api/model/components/barcodes/twod/A2DBarcode.java
+++ b/src/main/java/com/labelzoom/api/model/components/barcodes/twod/A2DBarcode.java
@@ -19,7 +19,7 @@
  */
 public abstract class A2DBarcode extends ABarcode
 {
-	public A2DBarcode() { this(null, false); }
+	protected A2DBarcode() { this(null, false); }
 
 	protected A2DBarcode(final A2DBarcode original, final boolean cloneData)
 	{
diff --git a/src/main/java/com/labelzoom/api/model/components/barcodes/twod/CBarcodeDataMatrix.java b/src/main/java/com/labelzoom/api/model/components/barcodes/twod/CBarcodeDataMatrix.java
index f31462c..1b527f5 100644
--- a/src/main/java/com/labelzoom/api/model/components/barcodes/twod/CBarcodeDataMatrix.java
+++ b/src/main/java/com/labelzoom/api/model/components/barcodes/twod/CBarcodeDataMatrix.java
@@ -13,7 +13,6 @@
  */
 
 import com.labelzoom.api.model.components.AComponent;
-import com.labelzoom.api.model.components.barcodes.ABarcode;
 import lombok.Getter;
 import lombok.Setter;
 
diff --git a/src/main/java/com/labelzoom/api/model/components/barcodes/twod/CBarcodeQRCode.java b/src/main/java/com/labelzoom/api/model/components/barcodes/twod/CBarcodeQRCode.java
index bdd5194..b38eb9e 100644
--- a/src/main/java/com/labelzoom/api/model/components/barcodes/twod/CBarcodeQRCode.java
+++ b/src/main/java/com/labelzoom/api/model/components/barcodes/twod/CBarcodeQRCode.java
@@ -13,7 +13,6 @@
  */
 
 import com.labelzoom.api.model.components.AComponent;
-import com.labelzoom.api.model.components.barcodes.ABarcode;
 import lombok.Getter;
 import lombok.Setter;
 
diff --git a/src/main/java/com/labelzoom/api/util/DpiUtility.java b/src/main/java/com/labelzoom/api/util/DpiUtility.java
index dfabe91..2552809 100644
--- a/src/main/java/com/labelzoom/api/util/DpiUtility.java
+++ b/src/main/java/com/labelzoom/api/util/DpiUtility.java
@@ -34,7 +34,7 @@ public DpiUtility(final int sourceDpi, final int targetDpi, final int sourceFont
 
     private float applyResize(final float sourceValue)
     {
-        return (float)(((double)sourceValue) * scalingFactor);
+        return (float)(sourceValue * scalingFactor);
     }
 
     private int applyResize(final int sourceValue)
@@ -44,7 +44,7 @@ private int applyResize(final int sourceValue)
 
     private float applyFontResize(final float sourceValue)
     {
-        return (float)(((double)sourceValue) * fontScalingFactor);
+        return (float)(sourceValue * fontScalingFactor);
     }
 
     public CLabel resizeLabel(final CLabel label)
diff --git a/src/main/java/com/labelzoom/api/util/HSLColor.java b/src/main/java/com/labelzoom/api/util/HSLColor.java
index ac6beff..ad73d8e 100644
--- a/src/main/java/com/labelzoom/api/util/HSLColor.java
+++ b/src/main/java/com/labelzoom/api/util/HSLColor.java
@@ -235,13 +235,7 @@ public float getSaturation()
 
     public String toString()
     {
-        String toString =
-                "HSLColor[h=" + hsl[0] +
-                        ",s=" + hsl[1] +
-                        ",l=" + hsl[2] +
-                        ",alpha=" + alpha + "]";
-
-        return toString;
+        return String.format("HSLColor[h=%f,s=%f,l=%f,alpha=%f]", hsl[0], hsl[1], hsl[2], alpha);
     }
 
     /**
diff --git a/src/main/java/com/labelzoom/api/util/ImageUtils.java b/src/main/java/com/labelzoom/api/util/ImageUtils.java
index a62778e..93a16ff 100644
--- a/src/main/java/com/labelzoom/api/util/ImageUtils.java
+++ b/src/main/java/com/labelzoom/api/util/ImageUtils.java
@@ -14,6 +14,8 @@ public class ImageUtils
     private static final int BLACK = Color.BLACK.getRGB();
     private static final int WHITE = Color.WHITE.getRGB();
 
+    private ImageUtils() {}
+
     public static BufferedImage cloneImage(final BufferedImage image)
     {
         // Clone original image
diff --git a/src/main/java/com/labelzoom/api/util/RotationUtility.java b/src/main/java/com/labelzoom/api/util/RotationUtility.java
index c40c0c1..ede900c 100644
--- a/src/main/java/com/labelzoom/api/util/RotationUtility.java
+++ b/src/main/java/com/labelzoom/api/util/RotationUtility.java
@@ -23,6 +23,8 @@
 
 public class RotationUtility
 {
+    private RotationUtility() {}
+
     public static int normalizeRotation(float degrees) { return normalizeRotation(Math.round(degrees)); }
 
     public static int normalizeRotation(int degrees)
diff --git a/src/test/java/com/labelzoom/api/DeepCopyTests.java b/src/test/java/com/labelzoom/api/DeepCopyTests.java
index ecd842e..9fa2fe8 100644
--- a/src/test/java/com/labelzoom/api/DeepCopyTests.java
+++ b/src/test/java/com/labelzoom/api/DeepCopyTests.java
@@ -13,7 +13,7 @@
 
 import static org.junit.jupiter.api.Assertions.*;
 
-public class DeepCopyTests
+class DeepCopyTests
 {
     private final ObjectMapper objectMapper = new ObjectMapper();
 
diff --git a/src/test/java/com/labelzoom/api/util/ImageUtilsTests.java b/src/test/java/com/labelzoom/api/util/ImageUtilsTests.java
index efce534..4d1184c 100644
--- a/src/test/java/com/labelzoom/api/util/ImageUtilsTests.java
+++ b/src/test/java/com/labelzoom/api/util/ImageUtilsTests.java
@@ -11,7 +11,7 @@
 
 import static org.junit.jupiter.api.Assertions.*;
 
-public class ImageUtilsTests
+class ImageUtilsTests
 {
     private final float DEFAULT_TOLERANCE = 0.1f;
 
diff --git a/src/test/java/com/labelzoom/api/util/LazyTests.java b/src/test/java/com/labelzoom/api/util/LazyTests.java
index 9b08a88..738c6c3 100644
--- a/src/test/java/com/labelzoom/api/util/LazyTests.java
+++ b/src/test/java/com/labelzoom/api/util/LazyTests.java
@@ -4,7 +4,7 @@
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 
-public class LazyTests
+class LazyTests
 {
     @Test
     void testLazy()