Changed package naming across all examples.

private-class-data/src/main/java/com/iluwatar/privateclassdata/App.java

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+package com.iluwatar.privateclassdata;
+
+/**
+ * 
+ * The Private Class Data design pattern seeks to reduce exposure of attributes 
+ * by limiting their visibility. It reduces the number of class attributes by 
+ * encapsulating them in single data object. It allows the class designer to 
+ * remove write privilege of attributes that are intended to be set only during 
+ * construction, even from methods of the target class.
+ * 
+ * In the example we have normal Stew class with some ingredients given in
+ * constructor. Then we have methods to enumerate the ingredients and to taste
+ * the stew. The method for tasting the stew alters the private members of the
+ * stew class.
+ * 
+ * The problem is solved with the Private Class Data pattern. We introduce
+ * ImmutableStew class that contains StewData. The private data members of
+ * Stew are now in StewData and cannot be altered by ImmutableStew methods.
+ *
+ */
+public class App {
+	
+    public static void main( String[] args ) {
+    	// stew is mutable
+    	Stew stew = new Stew(1, 2, 3, 4);
+    	stew.mix();
+    	stew.taste();
+    	stew.mix();
+    	
+    	// immutable stew protected with Private Class Data pattern
+    	ImmutableStew immutableStew = new ImmutableStew(2, 4, 3, 6);
+    	immutableStew.mix();
+    }
+}

private-class-data/src/main/java/com/iluwatar/privateclassdata/ImmutableStew.java

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+package com.iluwatar.privateclassdata;
+
+/**
+ * 
+ * Immutable stew class, protected with Private Class Data pattern
+ *
+ */
+public class ImmutableStew {
+
+	private StewData data;
+	
+	public ImmutableStew(int numPotatoes, int numCarrots, int numMeat, int numPeppers) {
+		data = new StewData(numPotatoes, numCarrots, numMeat, numPeppers);
+	}
+	
+	public void mix() {
+		System.out.println(String.format("Mixing the immutable stew we find: %d potatoes, %d carrots, %d meat and %d peppers",
+				data.getNumPotatoes(), data.getNumCarrots(), data.getNumMeat(), data.getNumPeppers()));
+	}
+}

private-class-data/src/main/java/com/iluwatar/privateclassdata/Stew.java

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+package com.iluwatar.privateclassdata;
+
+/**
+ * 
+ * Mutable stew class
+ *
+ */
+public class Stew {
+	
+	private int numPotatoes;
+	private int numCarrots;
+	private int numMeat;
+	private int numPeppers;
+	
+	public Stew(int numPotatoes, int numCarrots, int numMeat, int numPeppers) {
+		this.numPotatoes = numPotatoes;
+		this.numCarrots = numCarrots;
+		this.numMeat = numMeat;
+		this.numPeppers = numPeppers;
+	}
+	
+	public void mix() {
+		System.out.println(String.format("Mixing the stew we find: %d potatoes, %d carrots, %d meat and %d peppers",
+				numPotatoes, numCarrots, numMeat, numPeppers));
+	}
+	
+	public void taste() {
+		System.out.println("Tasting the stew");
+		if (numPotatoes > 0) { 
+			numPotatoes--; 
+		}
+		if (numCarrots > 0) { 
+			numCarrots--; 
+		}
+		if (numMeat > 0) { 
+			numMeat--; 
+		}
+		if (numPeppers > 0) { 
+			numPeppers--; 
+		}
+	}
+}

private-class-data/src/main/java/com/iluwatar/privateclassdata/StewData.java

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+package com.iluwatar.privateclassdata;
+
+/**
+ * 
+ * Stew ingredients
+ *
+ */
+public class StewData {
+
+	private int numPotatoes;
+	private int numCarrots;
+	private int numMeat;
+	private int numPeppers;
+	
+	public StewData(int numPotatoes, int numCarrots, int numMeat, int numPeppers) {
+		this.numPotatoes = numPotatoes;
+		this.numCarrots = numCarrots;
+		this.numMeat = numMeat;
+		this.numPeppers = numPeppers;
+	}
+
+	public int getNumPotatoes() {
+		return numPotatoes;
+	}
+
+	public int getNumCarrots() {
+		return numCarrots;
+	}
+
+	public int getNumMeat() {
+		return numMeat;
+	}
+
+	public int getNumPeppers() {
+		return numPeppers;
+	}
+}