[BAEL-2020] Differences between final, finally and finalize in Java (#4848)

* [BAEL-2020] Examples code

* [BAEL-2020] Moving classes into 'keywords' package

core-java/src/main/java/com/baeldung/keywords/finalize/FinalizeObject.java

@@ -0,0 +1,18 @@
+package com.baeldung.keywords.finalize;
+
+public class FinalizeObject {
+
+    @Override
+    protected void finalize() throws Throwable {
+        System.out.println("Execute finalize method");
+        super.finalize();
+    }
+
+    public static void main(String[] args) throws Exception {
+        FinalizeObject object = new FinalizeObject();
+        object = null;
+        System.gc();
+        Thread.sleep(1000);
+    }
+
+}

core-java/src/main/java/com/baeldung/keywords/finalkeyword/Child.java

@@ -0,0 +1,15 @@
+package com.baeldung.keywords.finalkeyword;
+
+public final class Child extends Parent {
+
+    @Override
+    void method1(int arg1, final int arg2) {
+        // OK
+    }
+
+/*    @Override
+    void method2() {
+        // Compilation error
+    }*/
+
+}

core-java/src/main/java/com/baeldung/keywords/finalkeyword/GrandChild.java

@@ -0,0 +1,5 @@
+package com.baeldung.keywords.finalkeyword;
+
+/*public class GrandChild extends Child {
+    // Compilation error
+}*/

core-java/src/main/java/com/baeldung/keywords/finalkeyword/Parent.java

@@ -0,0 +1,23 @@
+package com.baeldung.keywords.finalkeyword;
+
+public class Parent {
+
+    int field1 = 1;
+    final int field2 = 2;
+
+    Parent() {
+        field1 = 2; // OK
+//        field2 = 3; // Compilation error
+    }
+
+    void method1(int arg1, final int arg2) {
+        arg1 = 2; // OK
+//        arg2 = 3; // Compilation error
+    }
+
+    final void method2() {
+        final int localVar = 2; // OK
+//        localVar = 3; // Compilation error
+    }
+
+}

core-java/src/main/java/com/baeldung/keywords/finallykeyword/FinallyExample.java

@@ -0,0 +1,29 @@
+package com.baeldung.keywords.finallykeyword;
+
+public class FinallyExample {
+
+    public static void main(String args[]) throws Exception {
+        try {
+            System.out.println("Execute try block");
+            throw new Exception();
+        } catch (Exception e) {
+            System.out.println("Execute catch block");
+        } finally {
+            System.out.println("Execute finally block");
+        }
+
+        try {
+            System.out.println("Execute try block");
+        } finally {
+            System.out.println("Execute finally block");
+        }
+
+        try {
+            System.out.println("Execute try block");
+            throw new Exception();
+        } finally {
+            System.out.println("Execute finally block");
+        }
+    }
+
+}