初学者关于java的一个程序,关于类.构造方法可能还不是太清楚

来源：百度知道 编辑：UC知道 时间：2024/05/06 07:12:09
创建一个名为Branch的类.它具有的属性分别为字符串型的subName.整型的salary和整型的totalBooks.

在Branch类中定义calculateHrs()方法,用以执行计算,另外定义一个接受subName和totalBooks参数的参

数构造方法.

totalHrs=totalBooks*2(这条语句就是calculateHrs()中的方法)

再定义两个类Science和Arts,并通过它们调用Branch的calculateHrs()方法.
假定科学类和艺术类书籍的总数分别为10和14,输出结果应如下图所示.

科学学科的总时数是20
艺术学科的总时数是28

public class Branch{

String subName;
int totalBooks;
Branch(String name,int books) {
subName=name;
totalBooks=books;
}
void calculateHrs()
{
totalHrs=totalBooks*2;

}
}

class Science{
void getBranchHrs()
{
objBranch1.calculateHrs();
}
}
class Arts
{
objBranch2.calculateHrs();
}
void print()
{
System.out.println(subName+"总时数是"+totalHrs);

}

public static void main(String[]args)

public class Branch {
private String subName;
// private int salary;
private int totalBooks;

public Branch(String subName, int totalBooks) {
this.subName = subName;
this.totalBooks = totalBooks;
}

public int calculateHrs() {
return totalBooks * 2;
}

public void print() {
System.out.println(subName + "的总时数是" + calculateHrs());
}

public static void main(String[] args) {
Branch objBranch1 = new Science("科学学科", 10);
objBranch1.calculateHrs();
objBranch1.print();
Branch objBranch2 = new Arts("艺术学科", 14);
objBranch2.calculateHrs();
objBranch2.print();
}
}

class Science extends Branch {
public Science(String subName, int totalBooks) {
super(subName, totalBooks);
}
}

class Arts extends Branch {
public Arts(String subName, int totalBooks) {
s