Java Lesson 15: Common method for argument parsing

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The main class now looks as follows: 

public class MyClass {
    public static void main(String[] args) {
        Argument argument1 = ArgumentHelper.getArgument(0,args);
        Argument argument2 = ArgumentHelper.getArgument(1,args);
        printStuff(argument1);
        printStuff(argument2);
    }
 
    public static void printStuff(Argument data) {
        System.out.println("You specified: "+data.getValue());
    }
 
}

The IntArgument class: 

public class IntArgument extends Argument {
    private int intArgument;
    public IntArgument(int intArgument) {
        this.intArgument = intArgument;
    }
    public int getInt() {
        return intArgument;
    }
    public String getValue() {
        return String.valueOf(intArgument);
    }
}

The StringArgument class: 

public class StringArgument extends Argument {
    private String strArgument;
    public void setString(String arg) {
        this.strArgument = arg;
    }
    public String getString() {
        return strArgument;
    }
    public String getValue() {
        return String.valueOf(strArgument);
    }
}

And the Argument class looks as follows: 

public abstract class Argument {
    public abstract String getValue();
}

The program is as usual executed with: 

java MyClass 5 Hello

Your work is to implement the ArgumentHelper class so the program compiles and gives the following output: 

You specified: 5
You specified: Hello

You will need to be able to to check if an argument is a integer or a String, the following code illustrates an example of how this can be accomplished: 

int argument = 0;
try {
        argument = Integer.valueOf(parameterToCheckForStringOrInteger);
        // If we end up here it has successfully converted the parameter to an integer
        // The integer value is in the "argument" variable 
 
} catch (NumberFormatException e) {
        // If we end up here the parameter could not be converted to an integer
        // The String value is in the "parameterToCheckForStringOrInteger" variable 
 
}
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