Java中的输入扫描器

我要做的是读取3个文件，并将它们存储在一个名为Student的数组中，然后使用readIRstudent、readIR101和readIR102打印出读取的文件。我的问题是，当我执行代码时，只有第一个readIRstudent在我的测试类中实际打印出来，而且我也无法让数组工作。这是我的密码

import javax.swing.*;
import java.io.*;
import java.util.ArrayList;
import java.util.Scanner;

/**
 * Created by Lewis on 28/03/2015.
 */
public class Task2 {

public Scanner input;
int reg;
double ir101,ir102l;
double aggregate;
String student_name;

public void openIRstud()throws Exception{
    JFileChooser IRstudchooser = new JFileChooser();
    if(IRstudchooser.showOpenDialog(null) == JFileChooser.APPROVE_OPTION){
        java.io.File inFile = IRstudchooser.getSelectedFile();
        input = new Scanner(inFile);
        System.out.println("IRstudents file read successfully.");
    }
}
public void openIR101()throws Exception{
    JFileChooser IR101chooser = new JFileChooser();
    if(IR101chooser.showOpenDialog(null) == JFileChooser.APPROVE_OPTION){
        java.io.File inFile = IR101chooser.getSelectedFile();
        input = new Scanner(inFile);
        System.out.println("IR101 file read successfully.");
    }
}
public void openIR102()throws Exception{
    JFileChooser IR102chooser = new JFileChooser();
    if(IR102chooser.showOpenDialog(null) == JFileChooser.APPROVE_OPTION){
        java.io.File inFile1 = IR102chooser.getSelectedFile();
        input = new Scanner(inFile1);
        System.out.println("IR102 file read successfully.");
    }
}
public void readIRstud (){
    while(input.hasNext()){
        String irstudid = input.next();
        String irname = input.next();
        System.out.printf(" %s %s\n", irstudid, irname);
    }
    System.out.println("Complete.");
}
public void readIR101 (){
    while(input.hasNext()){
        String ir101studid = input.next();
        String ir101mark = input.next();
        System.out.printf(" %s %s\n", ir101studid, ir101mark);
    }
    System.out.println("Complete.");
}
public void readIR102 (){
    while(input.hasNext()){
        String ir102studid = input.next();
        String ir102mark = input.next();
        System.out.printf(" %s %s\n", ir102studid, ir102mark);
    }
    System.out.println("Complete.");
}
public void Student(){
    ArrayList<Student> students = new ArrayList<>();
    while (input.hasNext()) {
        String line = input.nextLine();
        Student e = new Student();
        e.reg = Integer.parseInt(line.split(" ")[0]);
        e.ir101 = Double.parseDouble(line.split(" ")[1]);
        students.add(e);
    }
}


}

---

还有ArrayList students部分=新ArrayList；表示此语言级别不支持菱形类型如何修复？若要修复此问题，请将此行替换为ArrayList students=new ArrayList；try ArrayList students=新建ArrayList；将学生放在第二个菱形中您发布的代码不会打印出任何内容，尽管它确实包含在调用时可以打印的方法。要想知道为什么有些东西没有被打印出来，你必须看看应该用来打印的代码。你的主要方法在哪里？还是构造器？这个类的流程不清楚。。。