类和对象java代码，java中类和对象怎么理解

java求关于一个类和对象的程序。。。。在线等。。急

public class Test {

public static void main(String args[]){

Pen aPen = new Pen();

aPen.setColor("red");

aPen.setLength(123);

aPen.setPrice(123.45f);

aPen.write();

System.out.println(aPen.getColor());

}

}

class Pen{

private String color;

private int length;

private float price;

public Pen() {

}

public Pen(String color, int length, float price) {

super();

this.color = color;

this.length = length;

this.price = price;

}

public void write(){

System.out.println(color);

}

public String getColor() {

return color;

}

public void setColor(String color) {

this.color = color;

}

public int getLength() {

return length;

}

public void setLength(int length) {

this.length = length;

}

public float getPrice() {

return price;

}

public void setPrice(float price) {

this.price = price;

}

}

java类和对象的关系是什么？

类和对象的关系是：类是对象的抽象，而对象是类的具体实例。

类是抽象的，不占用内存，而对象是具体的，占用存储空间。类是用于创建对象的蓝图，它是一个定义包括在特定类型的对象中的方法和变量的软件模板。

类与对象的关系就如模具和铸件的关系类的实例化结果就是对象，而对一类对象的抽象就是类，类描述了一组有相同属性和相同方法的对象。

java程序设计类与对象的基础题，求程序代码！

package tim;

public class SimpleTest {

public static void main(String[] args){

Simple aSimple = new Simple();

aSimple.setIntVariable(1111);

aSimple.setDoubleVariable(123.434);

aSimple.setStringVariable("我是字符串");

System.out.println("通过getter和setter方法打印:");

System.out.println("intVariable:"+aSimple.getIntVariable()+"\ndoubleVariable:"+aSimple.getDoubleVariable()+"\nstringVariable："+aSimple.getStringVariable());

System.out.println("\n通过toString方法打印:");

System.out.println(aSimple);

}

}

class Simple{

private int intVariable;

private double doubleVariable;

private String stringVariable;

/**变量的getter和setter方法**/

public int getIntVariable() {

return intVariable;

}

public void setIntVariable(int intVariable) {

this.intVariable = intVariable;

}

public double getDoubleVariable() {

return doubleVariable;

}

public void setDoubleVariable(double doubleVariable) {

this.doubleVariable = doubleVariable;

}

public String getStringVariable() {

return stringVariable;

}

public void setStringVariable(String stringVariable) {

this.stringVariable = stringVariable;

}

/**重写的toString方法**/

@Override

public String toString() {

String tostring = "intVariable:"+intVariable+"-----doubleVariable:"+doubleVariable+"-----stringVariable"+stringVariable;

return tostring;

}

}

//:~不懂可以问

/**结果：

通过getter和setter方法打印:

intVariable:1111

doubleVariable:123.434

stringVariable：我是字符串

通过toString方法打印:

intVariable:1111-----doubleVariable:123.434-----stringVariable我是字符串

*/

JAVA类与对象相关编程

public class Number {

private int n1;

private int n2;

public Number(){}

public Number(int n1, int n2) {

this.n1 = n1;

this.n2 = n2;

}

public int getN1() {

return n1;

}

public void setN1(int n1) {

this.n1 = n1;

}

public int getN2() {

return n2;

}

public void setN2(int n2) {

this.n2 = n2;

}

/**

* 加方法

* @return

*/

public static int addition(Number n){

int i=0;

i=n.getN1()+n.getN2();

return i;

}

public static int subtration(Number n){

int i=0;

i=n.getN1()-n.getN2();

return i;

}

public static int multiplication(Number n){

int i=0;

i=n.getN1()*n.getN2();

return i;

}

public static double division(Number n){

double i=0;

if(n.getN1()!=0){

i=n.getN1()/n.getN2();

}else{

System.out.println("被除数不可以为0");

}

return i;

}

}

public class test {

public static void main(String[] args) {

Number n=new Number(10,5);

System.out.println("加法："+Number.addition(n));

System.out.println("减法："+Number.subtration(n));

System.out.println("乘法："+Number.multiplication(n));

System.out.println("除法："+Number.division(n));

}

}

新手求java编程:关于类与对象的

是负数类还是复数类？

public class Test {

public static void main(String[] args) {

Patient april=new Patient();

april.setName("ZhangLi");

april.setSex('f');

april.setAge(33);

april.setWeight(154.72f);

april.setAllergies(true);

System.out.println("Name: "+april.getName());

System.out.println("Sex: "+april.getSex());

System.out.println("Age: "+april.getAge());

System.out.println("Weight: "+april.getWeight());

System.out.println("Allergies: "+april.getAllergies());

Complex c1 = new Complex(1, 2);

Complex c2 = new Complex(3, 4);

System.out.println(c1.add(c2));

System.out.println(c1.subtract(c2));

System.out.println(c1.multiply(c2));

System.out.println(c1.divide(c2));

}

}

class Patient {

private String name;

private char sex;

private int age;

private float weight;

private boolean allergies;

public String getName() {

return name;

}

public void setName(String name) {

this.name = name;

}

public char getSex() {

return sex;

}

public void setSex(char sex) {

this.sex = sex == 'M' ? sex : 'F';

}

public int getAge() {

return age;

}

public void setAge(int age) {

this.age = Math.max(1, age);

}

public float getWeight() {

return weight;

}

public void setWeight(float weight) {

this.weight = Math.max(0.0f, weight);

}

public boolean getAllergies() {

return allergies;

}

public void setAllergies(boolean allergies) {

this.allergies = allergies;

}

}

class Complex {

private double realPart;

private double imaginaryPart;

public Complex(double real, double imaginary) {

this.realPart = real;

this.imaginaryPart = imaginary;

}

public Complex add(Complex other) {

return new Complex(this.realPart + other.realPart,

this.imaginaryPart + other.imaginaryPart);

}

public Complex subtract(Complex other) {

return new Complex(this.realPart - other.realPart,

this.imaginaryPart - other.imaginaryPart);

}

public Complex multiply(Complex other) {

return new Complex(this.realPart * other.realPart -

this.imaginaryPart * other.imaginaryPart,

this.realPart * other.imaginaryPart +

this.imaginaryPart * other.realPart);

}

public Complex divide(Complex other) {

if (other.realPart == 0 other.imaginaryPart == 0) {

throw new ArithmeticException("Divided By 0");

}

if (this.realPart == 0 this.imaginaryPart == 0) {

return this;

}

Complex numerator = this.multiply(new Complex(other.realPart,

-other.imaginaryPart));

double denominator = other.realPart * other.realPart +

other.imaginaryPart * other.imaginaryPart;

return new Complex(numerator.realPart / denominator,

numerator.imaginaryPart / denominator);

}

public String toString() {

StringBuilder sb = new StringBuilder();

if (this.realPart != 0) {

sb.append(this.realPart);

}

if (this.imaginaryPart 0) {

sb.append(" + ").

append(this.imaginaryPart).

append("i");

} else if (this.imaginaryPart 0) {

sb.append(" - ").

append(Math.abs(this.imaginaryPart)).

append("i");

}

return sb.toString();

}

}

java类和对象的问题

对象是类实例化后的结果，如；Circle ccc = new Circle();那么这里的ccc就是一个对象。

而Circle bottom只是声明了一个变量，该变量的类型是Circle。

声明一个变量之后 就可以对变量就是赋值 了，如 bottom = new Circle();，此时bottom就是一个对象了。

可以把对象的声明和赋值放在一起写，即：Circle ccc = new Circle();

也可以分开写，即：Circle ccc ; ccc= new Circle();

类和对象java代码的介绍就聊到这里吧，感谢你花时间阅读本站内容，更多关于java中类和对象怎么理解、类和对象java代码的信息别忘了在本站进行查找喔。