1. //https://code.google.com/p/fresher01dn/source/browse/trunk/?r=13#trunk
%2FJavaEE_Day03%2Fsrc%2Fpk%2Fassignment01
public class Main {
private Shape shapeArray[];
private TwoDimensionalShape twoDArray[];
private ThreeDimensionalShape threeDimensionalShape[];
public Main() {
shapeArray = new Shape[6];
twoDArray = new TwoDimensionalShape[3];
threeDimensionalShape = new ThreeDimensionalShape[3];
Circle circle = new Circle(5);
Square square = new Square(5);
Triangle triangle = new Triangle(3, 4, 5);
Sphere sphere = new Sphere(5);
Cube cube = new Cube(3, 4);
Tetrahedron tetrahedron = new Tetrahedron(3, 5, 6);
shapeArray[0] = circle;
twoDArray[0] = circle;
shapeArray[1] = square;
twoDArray[1] = square;
shapeArray[2] = triangle;
twoDArray[2] = triangle;
shapeArray[3] = sphere;
threeDimensionalShape[0] = sphere;
shapeArray[4] = cube;
threeDimensionalShape[1] = sphere;
shapeArray[5] = sphere;
threeDimensionalShape[2] = tetrahedron;
}
public void displayShapeInfo() {
for (int i = 0; i < shapeArray.length; i++) {
System.out.print(shapeArray[i].getName() + " ");
shapeArray[i].print();
}
System.out.println("============================================");
for (int i = 0; i < twoDArray.length; i++) {
System.out.println(twoDArray[i].getName() + " co dien tich : "
+ twoDArray[i].getArea());
}
for (int i = 0; i < threeDimensionalShape.length; i++) {
System.out.println(threeDimensionalShape[i].getName() +" co
the tich "+ threeDimensionalShape[i].getVolume());
}
}
public static void main(String[] args) {
Main m = new Main();
m.displayShapeInfo();
}
}
============================================
public abstract class Shape {
// abstract methods
public abstract String getName();
public abstract void print();
}
=================================================
public abstract class TwoDimensionalShape extends Shape {

2. private int s1, s2,s3;
public TwoDimensionalShape( int s1, int s2,int s3) {
this.s1 = s1;
this.s2 = s2;
this.s3 = s3;
}
public int getS1() {
return s1;
}
public void setS1(int s1) {
this.s1 = s1;
}
public int getS3() {
return s3;
}
public void setS3(int s3) {
this.s3 = s3;
}
public int getS2() {
return s2;
}
public void setS2(int s2) {
this.s2 = s2;
}
public abstract int getArea();
}
class Circle extends TwoDimensionalShape{
public Circle( int radius) {
super( radius, radius,radius);
}
@Override
public int getArea() {
return (int)Math.PI *super.getS1()*super.getS1();
}
@Override
public String getName() {
// TODO Auto-generated method stub
return "Hinh tron";
}
@Override
public void print() {
}
System.out.println("co ban kinh = " + super.getS1()+" ");
}
class Square extends TwoDimensionalShape{
public Square(int canh) {
super(canh, canh,canh);

3. }
@Override
public int getArea() {
return super.getS1()*super.getS1();
}
@Override
public String getName() {
// TODO Auto-generated method stub
return "Hinh vuong";
}
@Override
public void print() {
// TODO Auto-generated method stub
System.out.println("Co canh = "+ super.getS1());
}
}
class Triangle extends TwoDimensionalShape{
public Triangle(int canh1, int canh2,int canh3) {
super(canh1, canh2, canh3);
// TODO Auto-generated constructor stub
}
@Override
public int getArea() {
// TODO Auto-generated method stub
int sTamGiac = 0;
//
s = căn[p.(p - a)(p - b)(p - c)]
//
trong ăó p = (a + b + c)2
float p = (super.getS1()+super.getS2()+super.getS3())/2;
sTamGiac =(int) Math.sqrt(p*( p -super.getS1())*(psuper.getS2())*(p-super.getS3()));
return sTamGiac;
}
@Override
public String getName() {
// TODO Auto-generated method stub
return "Hinh tam giac";
}
@Override
public void print() {
// TODO Auto-generated method stub
System.out.println("Co canh 1 = " +super.getS1() +" Canh 2 = "+
super.getS2() + " Canh 3 = "+ super.getS3());
}
}
====================================================
public abstract class ThreeDimensionalShape extends Shape {
public int getS1() {
return s1;
}
public void setS1(int s1) {
this.s1 = s1;
}

4. public int getS2() {
return s2;
}
public void setS2(int s2) {
this.s2 = s2;
}
public int getS3() {
return s3;
}
public void setS3(int s3) {
this.s3 = s3;
}
int s1, s2, s3;
public ThreeDimensionalShape(int s1, int s2, int s3) {
this.s1 = s1;
this.s2 = s2;
this.s3 = s3;
}
public abstract int getVolume();
}
class Sphere extends ThreeDimensionalShape {
public Sphere(int randius) {
super(randius, randius, randius);
}
@Override
public int getVolume() {
return (int) ((int) Math.PI * super.s1 * super.s1 * super.s1 *
0.75);
}
@Override
public String getName() {
return "Hinh cau ";
}
@Override
public void print() {
// TODO Auto-generated method stub
System.out.println("Co ban kinh = " + super.getS1());
}
}
class Cube extends ThreeDimensionalShape {
public Cube(int s1, int s2) {
super(s1, s2, 0);
}
@Override
public int getVolume() {
return (int) (Math.PI * super.s1 * super.s1 * super.s2);
}

5. @Override
public String getName() {
return "Hinh tru";
}
@Override
public void print() {
System.out.println("Co ban kinh
"
= " + super.getS1() + " chieu cao =
+ super.getS2());
}
}
class Tetrahedron extends ThreeDimensionalShape {
public Tetrahedron(int s1, int s2, int s3) {
super(s1, s2, s3);
// TODO Auto-generated constructor stub
}
@Override
public int getVolume() {
return super.s1 * super.s2 * super.s3;
}
@Override
public String getName() {
return "Hinh hop";
}
@Override
public void print() {
System.out.println("Chieu rong = " + super.s1 + " chiue dai = "
+ super.s2 + " chieu cao " + super.s3);
}
}
================================================================================
========
Cau 2
package pk.assignment02;
import java.util.ArrayList;
public class MyCharSequence implements CharSequence {
private ArrayList<Character> data = null;
public MyCharSequence() {
this.setData(new String());
}
@Override
public char charAt(int index) {
char c = (char) this.getData().get(index);
return c;
}
@Override
public int length() {
return getData().size();
}

6. @Override
public CharSequence subSequence(int start, int end) {
if (start < 0) {
throw new StringIndexOutOfBoundsException(start);
}
if (end > getData().size()) {
throw new StringIndexOutOfBoundsException(end);
}
if (start > end) {
throw new StringIndexOutOfBoundsException(start - end);
}
}
MyCharSequence ch = new MyCharSequence();
ch.setData(ch.getData().subList(start, end).toString());
return ch;
@Override
public String toString() {
String str = this.getData().toString();
return str;
}
public void setData(String data) {
ArrayList<Character> ar = new ArrayList<Character>();
char[] cArray = data.toCharArray();
for (int i = 0; i < cArray.length; i++) {
ar.add(cArray[i]);
}
this.data = ar;
}
public ArrayList<Character> getData() {
return data;
}
}
**
* Write a class that implements the CharSequence interface found in the
* java.lang package. (Javadoc API:
* http://download.oracle.com/javase/6/docs/api/java/lang/CharSequence.html)
* Your implementation should return the string backwards (in reverse order).
* Select one of the sentences from this home work to use as the data.
* Write a small main method to test your class; make sure to call all four
* methods.
*/
package pk.assignment02;
public class Program {
/**
* @param args
*/
public static void main(String[] args) {
MyCharSequence mcs = new MyCharSequence();
mcs.setData("Fresher01DN");
char c = mcs.charAt(2);
MyCharSequence mcs2 = (MyCharSequence) mcs.subSequence(0, 4);
String str = mcs.toString();
int mcsLength = mcs.length();
}

7. }