eight commit

Chap8_OOPs/Base.java

@@ -0,0 +1,18 @@
+class Base{
+	static int i = 0;
+	static{
+		m1();
+		System.out.println("base static block");
+	}
+
+	public static void main(String[] args){
+		m1();
+		System.out.println("base main");
+	}
+
+	public static void m1(){
+		System.out.println(j);
+	}
+
+	static int j = 20;
+}

Chap8_OOPs/CheckingDemo.java

@@ -0,0 +1,11 @@
+class CheckingDemo{
+	public static void main(String[] args){
+		Object o = new String("ashok");
+		System.out.println("hascode value is " + o.hashCode());
+		//System.out.println(o.length());
+
+		StringBuffer sb = (StringBuffer)o;
+		System.out.println(sb);
+
+	}
+}

Chap8_OOPs/ChildClass.java

@@ -0,0 +1,5 @@
+class ChildClass extends ParentClass{
+	ChildClass(){
+		System.out.println(this.hashCode());
+	}
+}

Chap8_OOPs/ChildInstance.java

@@ -0,0 +1,29 @@
+class ChildInstance extends ParentInstance{
+
+	int x = 100;
+
+	{
+		m2();
+		System.out.println("child first instance block");
+	}
+
+	ChildInstance(){
+		System.out.println("child constructor");
+	}
+
+	public static void main(String[] args){
+		ChildInstance p = new ChildInstance();
+		System.out.println("child main");
+	}
+
+	public void m2(){
+		System.out.println(y);
+	}
+
+	{
+	System.out.println("child second instance block");
+	}
+
+	int y = 200;
+
+}

Chap8_OOPs/ConstructorDemo.java

@@ -0,0 +1,21 @@
+class ConstructorDemo{
+	String name;
+	int rollno;
+
+	ConstructorDemo(String name, int rollno){
+		this.name = name;
+		this.rollno = rollno;
+	}
+
+	public static void main(String[] args){
+		ConstructorDemo d1 = new ConstructorDemo("durga", 1010);
+		ConstructorDemo d2 = new ConstructorDemo("softie", 2020);
+
+		System.out.println(d1);
+		System.out.println(d2);
+	}
+
+	public String toString(){
+		return name+" "+rollno;
+	}
+}

Chap8_OOPs/CountOfObjectsCreated.java

@@ -0,0 +1,39 @@
+class CountOfObjectsCreated{
+	static int count = 0;
+
+	{
+		count++;
+	}
+
+	CountOfObjectsCreated(){
+
+	}
+
+	CountOfObjectsCreated(int i){
+		this("Rani");
+	}
+
+	CountOfObjectsCreated(String s){
+		this(1000);
+	}
+
+	CountOfObjectsCreated(char c){
+
+	}
+
+	public static void main(String[] args){
+		CountOfObjectsCreated c1 = new CountOfObjectsCreated();
+		CountOfObjectsCreated c2 = new CountOfObjectsCreated(10);
+		CountOfObjectsCreated c3 = new CountOfObjectsCreated("sudha");
+		CountOfObjectsCreated c4 = new CountOfObjectsCreated('s');
+
+		System.out.println(count);
+
+
+		CountOfObjectsCreated c5 = new CountOfObjectsCreated();
+		CountOfObjectsCreated c6 = new CountOfObjectsCreated("rani");
+
+		System.out.println(count);
+
+	}
+}

Chap8_OOPs/Derived.java

@@ -0,0 +1,24 @@
+class Derived extends Base{
+	static int x = 100;
+
+	static{
+		m2();
+		System.out.println("derived first static block");
+	}
+
+	public static void main(String[] args){
+		m2();
+		System.out.println("derived main");
+	}
+
+	public static void m2(){
+		System.out.println(y);
+	}
+
+	static{
+		System.out.println("derived 
+		second static block");
+	}
+
+	static int y = 200;
+}

Chap8_OOPs/InitialisationDemo.java

@@ -0,0 +1,28 @@
+public class InitialisationDemo{
+
+	private static String m1(String msg){
+		System.out.println(msg);
+		return msg;
+	}
+
+	/*
+	private static void m1(String msg){
+		System.out.println(msg);
+	}
+	*/
+
+	public InitialisationDemo(){
+		m = m1("1");
+	}
+
+	{
+		m = m1("2");
+	}
+
+
+		String m = m1("3");
+
+	public static void main(String[] args){
+		Object o = new InitialisationDemo();
+	}
+}

Chap8_OOPs/InstanceControlFlowDemo.java

@@ -0,0 +1,28 @@
+class InstanceControlFlowDemo{
+
+	int i = 10;
+
+	{
+		m1();
+		System.out.println("first instance block");
+	}
+
+	InstanceControlFlowDemo(){
+		System.out.println("Constructor");
+	}
+
+	public static void main(String[] args){
+		InstanceControlFlowDemo d = new InstanceControlFlowDemo();
+		System.out.println("main");
+	}
+
+	public void m1(){
+		System.out.println(j);
+	}
+
+	{
+		System.out.println("second instance block");
+	}
+
+	int j = 20;
+}

Chap8_OOPs/MixInitialisationDemo.java

@@ -0,0 +1,21 @@
+class MixInitialisationDemo{
+
+	private static String m1(String msg){
+		System.out.println(msg);
+		return msg;
+	}
+
+	static String m = m1("1");
+
+	{
+		m = m1("2");
+	}
+
+	static{
+		m = m1("3");
+	}
+
+	public static void main(String[] args){
+		Object o = new MixInitialisationDemo();
+	}
+}

Chap8_OOPs/ParentClass.java

@@ -0,0 +1,5 @@
+class ParentClass{
+	ParentClass(){
+		System.out.println(this.hashCode());
+	}
+}

Chap8_OOPs/ParentInstance.java

@@ -0,0 +1,29 @@
+class ParentInstance{
+
+	int i = 10;
+
+	{
+		m1();
+		System.out.println("parent instance block");
+	}
+
+	ParentInstance(){
+		System.out.println("parent constructor");
+	}
+
+	public static void main(String[] args){
+		ParentInstance p = new ParentInstance();
+		System.out.println("parent main");
+	}
+
+	public void m1(){
+		System.out.println(j);
+	}
+
+	int j = 20;
+}
+
+// 0
+// parent instance block
+// parent constructor
+// parent main

Chap8_OOPs/SingleClientObject.java

@@ -0,0 +1,16 @@
+class SingleClientObject{
+	public static void main(String[] args){
+		SingleTonDemo singleObj = SingleTonDemo.getSingleObject();
+		SingleTonDemo singleObj2 = SingleTonDemo.getSingleObject();
+		SingleTonDemo singleObj3 = SingleTonDemo.getSingleObject();
+
+		System.out.println(singleObj.hashCode());
+		System.out.println(singleObj2.hashCode());
+		System.out.println(singleObj3.hashCode());
+
+		System.out.println(singleObj == singleObj2);
+		System.out.println(singleObj == singleObj3);
+		System.out.println(singleObj2 == singleObj3);
+
+	}
+}

Chap8_OOPs/SingleTonDemo.java

@@ -0,0 +1,11 @@
+class SingleTonDemo{
+	private static SingleTonDemo d = new SingleTonDemo();
+
+	private SingleTonDemo(){
+
+	}
+
+	public static SingleTonDemo getSingleObject(){
+		return d;
+	}
+}

Chap8_OOPs/StaticDemo.java

@@ -0,0 +1,24 @@
+class StaticDemo{
+
+	/*
+	static{
+		System.out.println(x);
+	}
+	
+	static int x = 10;
+	*/
+
+	static{
+		m1();
+	}
+
+	public static void m1(){
+		System.out.println(x);
+	}
+
+	static int x = 10;
+
+	public static void main(String[] args){
+			System.out.println("last one to execute");
+	}
+}

Chap8_OOPs/Test.java

@@ -0,0 +1,22 @@
+class Test{
+
+	public void m1(int i){
+		System.out.println("integer");
+	}
+
+	public void m1(String i){
+		System.out.println("string");
+	}
+
+	public void m1(double i){
+		System.out.println("double");
+	}
+
+	public static void main(String[] args){
+		Test t = new Test();
+
+		t.m1(10);
+		t.m1("durga");
+		t.m1(10.29f);
+	}
+}

Chap8_OOPs/TestClass.java

@@ -0,0 +1,6 @@
+class TestClass{
+	public static void main(String[] args){
+		ChildClass c = new ChildClass();
+		System.out.println(c.hashCode());
+	}
+}