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// I01 interface
/* 2. itf with m/t w/o abs keyword. */
interface I1 {
void show();
}
// compile successfully
/* 3. itf with m/t with abs kwyword.*/
interface I1 {
abstract void show();
}
// compile successfully
/* 4. itf with abs. m/t with public a/m. */
interface I1 {
public abstract void show();
}
// compile successfully
/* 7.itf with concrete m/t.*/
interface I1 {
void show();
void display(){
System.out.println("hi");
}
}
// interface abstract methods cannot have body
/* 8. itf with concrete m/t ( default keyword. */
interface I1 {
void show();
default void display(){
System.out.println("hi");
}
}
// compile successfully
/* 9. itf with concrete m/t ( static keyword. */
interface I1 {
void show();
static void display(){
System.out.println("hi");
}
}
// compile successfully
/* 10. itf with variable */
interface I1 {
int a = 10;// default = public static final
void show();
}
// compile successfully
// deafutl public static final
/* 11. itf with var. having public static final keyword.*/
interface I1 {
public static final int a = 10;
void show();
}
// compile successfully
/* 12. cls i/h itf m/t with weeker (default ) a/m. */
interface I1 {
void show();
}
class I12 implements I1{
void show(){// default
System.out.println("class i/h i/t m/t");
}
}
// show() in I12 cannot implement show() in I1
// attempting to assign weaker access privileges; was public
/* 13. cls i/h itf m/t with public a/m. */
interface I1 {
void show();
}
class I13 implements I1{
public void show(){
System.out.println("class i/h i/t m/t with public keyword");
}
}
// compile successfully
/* 14. itf obj in main m/t , not acceptable. */
interface I1 {
void show();
}
class I14 implements I1{
public void show(){
System.out.println("interface object in main");
}
public static void main(String[] args) {
I1 i3 = new I1();
}
}// I1 is abstract; cannot be instantiated
/* 15. make obj of cld. cls. and the use ts abs m/t */
interface I1 {
void show();
}
class I15 implements I1{
public void show(){
System.out.println("show m/t");
}
public static void main(String[] args) {
I15 i1 = new I15();
i1.show();
}
}// compile successfully
/* 16. implment two itf and only create body of one itf. */
interface I1 {
void show();
}
interface I2{
void display();
}
class I16 implements I1, I2{// only one itf body
public void show(){
System.out.println("inherit m/t using public keyword");
}
public static void main(String[] args) {
I16 i1 = new I16();
i1.show();
}
}
// I16 is not abstract and does not override abstract method display() in I2
/* 15. implemnt two itf and create body of both itf. */
interface I1 {
void show();
}
interface I2{
void display();
}
class I17 implements I1, I2{
public void show(){
System.out.println("show");
}
public void display(){
System.out.println("display");
}
public static void main(String[] args) {
I17 i1 = new I17();
i1.show();
i1.display();
}
}
// show
// display
