Initial data commit

Task/Enforced-immutability/Java/enforced-immutability-1.java

@@ -0,0 +1,4 @@
+final int immutableInt = 4;
+int mutableInt = 4;
+mutableInt = 6; //this is fine
+immutableInt = 6; //this is an error

Task/Enforced-immutability/Java/enforced-immutability-2.java

@@ -0,0 +1,5 @@
+final String immutableString = "test";
+immutableString = new String("anotherTest"); //this is an error
+final StringBuffer immutableBuffer = new StringBuffer();
+immutableBuffer.append("a"); //this is fine and it changes the state of the object
+immutableBuffer = new StringBuffer("a"); //this is an error

Task/Enforced-immutability/Java/enforced-immutability-3.java

@@ -0,0 +1,25 @@
+public class Immute{
+    private final int num;
+    private final String word;
+    private final StringBuffer buff; //still mutable inside this class, but there is no access outside this class
+
+    public Immute(int num){
+        this.num = num;
+        word = num + "";
+        buff = new StringBuffer("test" + word);
+    }
+
+    public int getNum(){
+        return num;
+    }
+
+    public String getWord(){
+        return word; //String objects are immutable so passing the object back directly won't harm anything
+    }
+
+    public StringBuffer getBuff(){
+        return new StringBuffer(buff);
+        //using "return buff" here compromises immutability, but copying the object via the constructor makes it ok
+    }
+    //no "set" methods are given
+}