将对象传递给单独类中的方法时遇到麻烦

Question

So I am writing my own class for the first time and the only method that I have not been able to figure out is the compareTo method which is supposed to have "one parameter: a SavingsAccount object. Name it what you want."

public int compareTo(SavingsAccount secAccount)
{
    int result;
    if ( balance > secAccount.getBalance() )
        result = 1;
    else if ( balance == secAccount.getBalance() )
        result = 0;
    else
        result = -1;

    return result;
}

When I try to compile i get this error:
error: missing return statement }

in the client (written by my professor, which I am not supposed to edit) this is the line that calls on my compareTo method:

if ( savings1.compareTo(savings2) > 0 )
        System.out.println("[client] Savings1 has the larger balance");
    else if (savings1.compareTo(savings2) == 0 )
        System.out.println("[client] Savings1 and Savings2 "
        + "have the same balance");
    else
        System.out.println("[client] Savings2 has the larger balance");

From what I understand the argument savings2 is being passed to compareTo and then in my SavingsAccount class, the parameter is secAccount as an object SavingsAccount.

Answer 1

Instead of declaring a int result you can do something like this.

public int compareTo(SavingsAccount secAccount)
{
    if ( balance > secAccount.getBalance() )
        return 1;
    else if ( balance == secAccount.getBalance() )
        return 0;
    else
        return -1;
}

Unless you need that result variable this will work. There's no need to write extra code setting values of variables when you can just do it this way.

Answer 2

You may just have a stray curly brace. Here is a complete working example:

Contents of file Test.java:

package com.jlb;

public class Test{

    public static void main(String[] args)
    {
        SavingsAccount savings1 = new SavingsAccount(200);
        SavingsAccount savings2 = new SavingsAccount(100);

        if ( savings1.compareTo(savings2) > 0 )
            System.out.println("[client] Savings1 has the larger balance");
        else if (savings1.compareTo(savings2) == 0 )
            System.out.println("[client] Savings1 and Savings2 "
            + "have the same balance");
        else
            System.out.println("[client] Savings2 has the larger balance");
    }


}

Contents of file SavingsAccount.java:

package com.jlb;

public class SavingsAccount {

    private int balance = 0;

    public SavingsAccount(int amount){
        this.balance = amount;
    }
    public int getBalance(){
        return this.balance;
    }

    public int compareTo(SavingsAccount secAccount)
    {
        int result;
        if ( balance > secAccount.getBalance() )
            result = 1;
        else if ( balance == secAccount.getBalance() )
            result = 0;
        else
            result = -1;

        return result;
    }
}

You can test it by changing the values when you create savings1 and savings2, then run it as a Java program in Eclipse or whatever your favorite IDE is.