Question

类#是公共的，应在名为#.java的文件中声明

class Complex{
private int realPart;
private int imaginPart;
Complex(){
this.realPart = 0;
this.imaginPart = 0;
}
Complex(int realPart, int imaginPart){
this.realPart = realPart;
this.imaginPart = imaginPart;
}
public void setRealPart(int realPart){
this.realPart = realPart;
}
public void setImaginPart(int imaginPart){
this.imaginPart = imaginPart;
}
public int getRealPart(){
return this.realPart;
}
public int getImaginPart(){
return this.imaginPart;
}
Complex complexAdd(Complex a){
int realPart = this.realPart + a.getRealPart();
int imaginPart = this.imaginPart + a.getImaginPart();
return new Complex(realPart, imaginPart);
}
public String toString(){
if(this.imaginPart == 0) return "" + this.realPart;
else if(this.imaginPart > 0) return "" + this.realPart + "+" + this.imaginPart + "i";
else return "" + this.realPart + this.imaginPart + "i";
}
}
public class TextComplex{
public static void main(String[] args){
Complex a = new Complex(1,2);
Complex b = new Complex(3,4);
Complex sum = a.complexAdd(b);
System.out.println("(" + a + ")" + "+" + "(" + b + ")" + "=" + "(" + sum + ")");
a.setRealPart(2);
a.setImaginPart(3);
b.setRealPart(b.getRealPart() * 2);
b.setImaginPart(b.getImaginPart() *2);
sum = a.complexAdd(b);
System.out.println("(" + a + ")" + "+" + "(" + b + ")" + "=" + "(" + sum + ")");
}
}

Answer 1

一个.java文件中只允许出现一个public class,并且用public修饰的类作为文件的名字,例如A.java中
public class A{
//do something
}
class B{
//do something
}
class C{
//do something
}

Answer 2

文件名应是 TextComplex.java,因为 TextComplex类是public的。

Answer 3

你这个文件的文件名应该是TextComplex.java

Answer 4

这是干什么啊，不明白作者要表达什么意思。