Java / BlueJ-无法打印出ArrayList中的项目

Question

I'm having issues with looping/returning correct items in my ArrayList. When I run my program, and use my accessor method, it returns items in the terminal such as "Member@13243" instead of the actual member I'm trying to return. I have two classes, one "Family" and one "Member".

My tasks are: 2) getMembers() – returns a List of members that had been added to the Family. 3) getMembers(string s) - returns a List of members that had been added to the Family. a. An error should be output if the specified sex is not valid. 4) showMembers() – use Member's toString to print a list of Members that had been added to a Family 5) showMembers(string s) – use Member's toString to print a list of Members that had been added to a Family of the specified sex.

My code for class Family:

  public class Family

 {
    // instance variables - replace the example below with your own
   public int ID;
   public String FamilyName;
   public String Address;
   public String City;
   public String State;
   public String ZipCode;
   public ArrayList<Member> list;

   public Family(int ID, String FamilyName, String Address, String City, String State, String        ZipCode)
   {
    this.ID = ID;
    this.FamilyName = FamilyName;
    this.Address = Address;
    this.City = City;
    this.State = State;
    this.ZipCode = ZipCode;
    list = new ArrayList<Member>();
   }

public void addMember(Member m )  {

   list.add(m);

}


private ArrayList<Member> getMembers(){
return list;
}


public void showAll(){
System.out.println(ID);  
System.out.println(Member.memberName);
System.out.println(FamilyName);
System.out.println(Member.memberSex); 
System.out.println(Address); 
System.out.println(City); 
System.out.println(State); 
System.out.println(ZipCode); 

}

My code for class Member:

 public class Member 
 {

   private String memberName;
   private String memberSex;



   public Member(String memberName, String memberSex){

    this.memberName = memberName;
    this.memberSex = memberSex;


     if (memberSex == "M"){
    memberSex = "M";}

    else if (memberSex == "F"){
    memberSex = "F";}

    else System.out.println("Please enter M or F for sex");


    }

    public String getMemberName(){
        return memberName;
    }

    public String getMemberSex(){
       return memberSex;
    }

Answer 1

You should override toString method in your Member class.

 @Override
    public String toString() {
    return "Member: "+memberName, "Sex "+memberSex;

}