打印出数组列表中的所有对象 [英] Printing out all the objects in array list

问题描述

  

可能重复：结果
  如何打印正确的方式对象中的内容？

我需要能够在我的数组列表打印出来的学生对象（所有变量）。这可能吗？当我尝试打印输出这样的事情例如student.Student@82701e。我认为这是十六进制或东西。

 包学生;公共类学生{    私人字符串studentName;
    私人字符串studentNo;
    私人字符串电子邮件;
    私人诠释年;
    公益助学（）{
        this.studentName = NULL;
        this.studentNo = NULL;
        this.email = NULL;
        this.year = -1;
    }    公益助学（字符串n名称，字符串nNum，字符串nEmail，诠释NYR）{
        this.studentName = n名称;
        this.studentNo = nNum;
        this.email = nEmail;
        this.year = NYR;
    }    公共无效setStudentName（字符串newStudentName）{
        this.studentName = newStudentName;
    }    公共无效setStudentNo（字符串newStudentNo）{
        this.studentNo = newStudentNo;
    }    公共无效setEmail（字符串NEWEMAIL）{
        this.email = NEWEMAIL;
    }    公共无效setYear（INT NEWYEAR）{
        this.year = NEWYEAR;
    }    公共字符串getStudentName（）{
        返回studentName;
    }    公共字符串getStudentNo（）{
        返回studentNo;
    }    公共字符串getEmail（）{
        返回的电子邮件;
    }    公众诠释了getYear（）{
        返回年;
    }
}包学生;进口的java.util.ArrayList;
进口的java.util.List;
进口java.util.Scanner中;公共类studentTest {    公共静态无效的主要（字串[] args）{
        扫描仪输入=新的扫描仪（System.in）;        清单＆LT;的Student GT;学生=新的ArrayList（）;
        学生student1 =新学生（）;        student1.setStudentName（鲍勃·马利）;
        student1.setStudentNo（N0002）;
        student1.setEmail（[e-mail]）;
        student1.setYear（2）;        Students.add（student1）;        学生STUDENT2 =新学生（）;        student2.setStudentName（比尔·哈维）;
        student2.setStudentNo（N0003）;
        student2.setEmail（[e-mail]）;
        student2.setYear（2）;        Students.add（STUDENT2）;        学生学生三=新学生（）;        student3.setStudentName（约翰豆）;
        student3.setStudentNo（N0004）;
        student3.setEmail（[e-mail]）;
        student3.setYear（2）;        Students.add（学生三）;
        的System.out.println（添加新同学：）;
        的System.out.println（输入学生加号：）;
        INT countStudents = input.nextInt（）;        的for（int i = 0; I＆LT; countStudents;我++）{
            学生newStudents =新学生（）;
            的System.out.println（学生输入详细信息：+（I + 1））;            的System.out.println（输入名称：）;
            newStudents.setStudentName（input.next（））;            的System.out.println（输入号码：）;
            newStudents.setStudentNo（input.next（））;的System.out.println（按学号搜索：）;            的System.out.println（输入电子邮件：）;
            newStudents.setEmail（input.next（））;            的System.out.println（输入年份：）;
            newStudents.setYear（input.nextInt（））;
            Students.add（newStudents）;
        }
    }
}
 

解决方案

覆盖的toString（）方法学生类，如下：

  @覆盖
   公共字符串的toString（）{
        返回（StudentName：+ this.getStudentName（）+
                    学生没有+ this.getStudentNo（）+
                    电子邮件：+ this.getEmail（）+
                    年：+ this.getYear（））;
   }
 

Possible Duplicate:
How to print object content in correct way?

I need to be able to print out the Student objects(all variables) in my array list. Is this possible? When i try to print it outputs this sort of thing e.g student.Student@82701e. I think it's hexadecimal or something

package student;

public class Student {

    private String studentName;
    private String studentNo;
    private String email;
    private int year;


    public Student() {
        this.studentName = null;
        this.studentNo = null;
        this.email = null;
        this.year = -1;
    }

    public Student(String nName, String nNum, String nEmail, int nYr) {
        this.studentName = nName;
        this.studentNo = nNum;
        this.email = nEmail;
        this.year = nYr;
    }

    public void setStudentName(String newStudentName) {
        this.studentName = newStudentName;
    }

    public void setStudentNo(String newStudentNo) {
        this.studentNo = newStudentNo;
    }

    public void setEmail(String newEmail) {
        this.email = newEmail;
    }

    public void setYear(int newYear) {
        this.year = newYear;
    }

    public String getStudentName() {
        return studentName;
    }

    public String getStudentNo() {
        return studentNo;
    }

    public String getEmail() {
        return email;
    }

    public int getYear() {
        return year;
    }
}

package student;

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

public class studentTest {

    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);



        List<Student> Students = new ArrayList();


        Student student1 = new Student();

        student1.setStudentName("Bob Marley");
        student1.setStudentNo("N0002");
        student1.setEmail("[e-mail]");
        student1.setYear(2);

        Students.add(student1);

        Student student2 = new Student();

        student2.setStudentName("Bill Harvey");
        student2.setStudentNo("N0003");
        student2.setEmail("[e-mail]");
        student2.setYear(2);

        Students.add(student2);

        Student student3 = new Student();

        student3.setStudentName("John Beans");
        student3.setStudentNo("N0004");
        student3.setEmail("[e-mail]");
        student3.setYear(2);

        Students.add(student3);


        System.out.println("Add new students: ");
        System.out.println("Enter number of students to add: ");
        int countStudents = input.nextInt();

        for (int i = 0; i < countStudents; i++) {
            Student newStudents = new Student();


            System.out.println("Enter details for student: " + (i + 1));

            System.out.println("Enter name: ");
            newStudents.setStudentName(input.next());

            System.out.println("Enter Number: ");
            newStudents.setStudentNo(input.next());System.out.println("Search by student number: ");



            System.out.println("Enter email: ");
            newStudents.setEmail(input.next());

            System.out.println("Enter year: ");
            newStudents.setYear(input.nextInt());
            Students.add(newStudents);
        }


    }
}

解决方案

Override toString() method in Student class as below:

   @Override
   public String toString() {
        return ("StudentName:"+this.getStudentName()+
                    " Student No: "+ this.getStudentNo() +
                    " Email: "+ this.getEmail() +
                    " Year : " + this.getYear());
   }

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