数组排序是的类型转化问题

Question

public class MaoPao2 {
@Test
public void test2() {
Student[] st = new Student[100];
Scanner sc = new Scanner(System.in);
int n = Integer.parseInt(sc.nextLine());
for (int i = 0; i < n; i++) {
String name = sc.nextLine();
int degree = Integer.parseInt(sc.nextLine());
Student s = new Student();
s.setName(name);
s.setDegree(degree);
st[i] = s;
}
Arrays.sort( st);
for (int i = 0; i < n; i++) {
System.out.println(st[i].getName() + ":" + st[i].getDegree());
}
}

}
package paixu_Code;

public class Student {
String name;
int degree;

public Student() {

}

public Student(String name, int degree) {
    super();
    this.name = name;
    this.degree = degree;
}

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}

public int getDegree() {
    return degree;
}

public void setDegree(int degree) {
    this.degree = degree;
}

}
报的错是：
java.lang.ClassCastException: paixu_Code.Student cannot be cast to java.lang.Comparable
at paixu_Code.MaoPao2.test2(MaoPao2.java:64)
即：Arrays.sort( st);转化错误

Answer 1

这个类型转换异常比较常见，原因可能是你输入了double类型，就不能转换为int,如果要转需要强转