初学者的一个程序问题

Question

package Package_03;
import java.util.*;
import java.io.*;
public class StudentArray {
public static void main(String args[])
{
Student student=new Student();
student.scorePrint(80.00);
// student.cont();
}
}
class Student{
private double score[]=null;
int size=5;
public Student(){
double score[]=new double[size];
InputStreamReader ist=new InputStreamReader(System.in);
BufferedReader br=new BufferedReader(ist);
for(int i=0;i System.out.println("请输入第"+(i+1)+"个学生的成绩");
try {
score[i]=Float.parseFloat(br.readLine());
} catch (NumberFormatException e) {
// TODO 自动生成 catch 块
e.printStackTrace();
} catch (IOException e) {
// TODO 自动生成 catch 块
e.printStackTrace();
}
}
for(int i=0;i System.out.print(score[i]+"\t");
}
}
//输入成绩，打印该学生的学号
public void scorePrint(double flag){
System.out.println("调用了scorePrint方法！");
for(int i=0;i {
if(score[i]==flag)
System.out.println("成绩为："+flag+"的学生有："+(i+1)+"\t");
}
}
//统计各分数段的学生人数
/*public void cont(){
int you=0;
int liang=0;
int zhong=0;
int cha=0;
int bujige=0;
for(int i=0;i {
if(score[i]90)
you++;
else if(score[i]<=90&&score[i]>80)
liang++;
else if(score[i]<=80&&score[i]>70)
zhong++;
else if(score[i]<=70&&score[i]>60)
cha++;
else
bujige++;
}
System.out.println("成绩为优的学生个数是："+you);
System.out.println("成绩为良的学生个数是："+liang);
System.out.println("成绩为中的学生个数是："+zhong);
System.out.println("成绩为差的学生个数是："+cha);
System.out.println("成绩为不及格的学生个数是："+bujige);
}*/
public double[] getScore() {
return score;
}
public void setScore(double[] score) {
this.score = score;
}

Answer 1

这两行有问题：

private double score[]=null;

double score[]=new double[size];