Hey I have started Java Recently and I was wonder if someone could help me!

I have partly created a program which gets Dates and Times and Stores these in array and it just a little program which works out your hours and your salary. However I want to use a Array which can store lots of new dates and times for example if they Bunch in at 1pm it should store this is Array[] if someone could help me out it out be appreciated and feel free to comment about my code.

Sorry I didnt bother Making Methods;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.*;

public class mainclass {
public static void main(String[]args){

System.out.println("\t" + "\t" + "\t" + "Welcome to HourlyRate");
System.out.println("1. Punch In" + "\t" + "2. Punch Out" + "\t" + "3. Set Hourly Rate" + "\t" + "4. Calcuate Wage" + "\t" + "5. Exit Program");
// Scanner Class

String punchIn[] = new String[1];
String punchOut[] = new String [7];
int wage[] = new int [7];

// hourly rate
float hourlywage = 0.00f;
// Case Navigation
int navmenu = 0;

// User Input

Scanner userinput = new Scanner(System.in);

//Date and Time

DateFormat df = DateFormat.getDateTimeInstance (DateFormat.MEDIUM, DateFormat.MEDIUM, new Locale ("en", "EN"));

navmenu = userinput.nextInt(); //