2020年8月6日Java学习日记

学习内容：

1、复数类

public class Complex {
    private double real,imag;
    public  void setvalue(double a,double b) {
        real=a;
        imag=b;
    }
    public double getReal() {
        return real;
    }
    public double getImag() {
        return imag;
    }
    public void display() {
        System.out.print(real);
        if(imag>0)
            System.out.println("+"+imag+"i");
        else
            System.out.println(imag+"i");
    }
    public Complex conjugate() {
        Complex c=new Complex();
        c.real=real;
        c.imag=-1*imag;
        return c;
    }
    public static void main(String[] args) {
        Complex con=new Complex();
        Complex con1=new Complex();
        con.setvalue(3.2, 5.6);
        System.out.println("复数的实部为:"+con.getReal());
        System.out.println("复数的虚部为:"+con.getImag());
        System.out.print("复数为:");
        con.display();
        con1=con.conjugate();
        System.out.print("该复数的共轭复数为:");
        con1.display();
    }
}

 2、学生类

import java.util.Scanner;
public class Student1 {
    private int age;
    private String name;
    public void Input(int a,String n) {
        age=a;
        name=n;
    }
    public void Output() {
        System.out.println("姓名:"+name+"\t"+"年龄:"+age);
    }
    public static void main(String[] args) {
        Student1[] stu=new Student1[3];
        Scanner con=new Scanner(System.in);
        for(int i=0;i<3;i++) {
            stu[i]=new Student1();
            System.out.println("请输入第"+(i+1)+"位同学信息(姓名、年龄):");
            stu[i].name=con.next();
            stu[i].age=con.nextInt();
            stu[i].Input(stu[i].age, stu[i].name);
        }
        for(int i=0;i<3;i++) {
            System.out.print("第"+(i+1)+"位同学:");
            stu[i].Output();
        }
    }
}

 3、点类

import java.util.Scanner;
public class Point1 {
    private float x,y,z;
    public void Input() {
        Scanner con=new Scanner(System.in);
        System.out.println("请输入坐标(x、y、z):");
        x=con.nextFloat();
        y=con.nextFloat();
        z=con.nextFloat();
    }
    public float getX() {return x;}
    public float getY() {return y;}
    public float getZ() {return z;}
    public void Output() {
        System.out.println("坐标为:("+x+","+y+","+z+")");
    }
    public static void main(String[] args) {
        Point1 p=new Point1();
        p.Input();
        p.Output();
        System.out.println("横坐标为:"+p.getX());
        System.out.println("纵坐标为:"+p.getY());
        System.out.println("竖坐标为:"+p.getZ());
    }
}

 4、线段类

import java.lang.Math;
public class Line1 {
    private Point1 p1=new Point1();
    private Point1 p2=new Point1();
    public void Input() {
        System.out.println("请输入线段的起点和终点坐标:");
        p1.Input();
        p2.Input();
    }
    public void display() {
        double d;
        d=Math.sqrt((p1.getX()-p2.getX())*(p1.getX()-p2.getX())+(p1.getY()-p2.getY())*(p1.getY()-p2.getY())+(p1.getZ()-p2.getZ())*(p1.getZ()-p2.getZ()));
        System.out.printf("线段的长度为:%-9.4f",d);
    }

    public static void main(String[] args) {
        Line1 l=new Line1();
        l.Input();
        l.display();
    }
}