Dúvidas com código!

import java.util.Scanner;

public class Study {	
	public static void main (String[] args){
		Scanner input = new Scanner(System.in);			
		Vector[] object = new Vector[5];

		int[] nums = new int[2]; 	
		nums[0] = 3;
		nums[1] = 2;	

		System.out.println("Test "+Vector.product_Numbers(nums)+""); // send int array to static method.	

		while(true) {
			System.out.println("Create Form: [1]\nView Form: [2]\nForm Search: [3]\nDelete All Forms: [4]\nSystem Exit: [5]");
			int main_menu = input.nextInt();
	
			switch(main_menu) {
				case 1:
					for (int count = 0; count < 5; count++){ // input data.
						System.out.printf("Person (%d), Please, input your name: ", count+1);
						String name = input.next();

						System.out.printf("Person (%d), Please, input your age: ", count+1);
						int age = input.nextInt();
	
						object[count] = new Vector(name, age); //create a new array object.										
					} 
					break;
				case 2:
					try {
						Vector.sortArray(object);
						break;
					}
					catch(NullPointerException ex){
						System.out.println("Please, first create a form.");
						break;
					}
				case 3:
					try {
						Vector.searchArray(object);
						break;
					} 
					catch(NullPointerException ex){
						System.out.println("Please, first create a form.");
					}
				case 4: 
					try {
						Vector.deleteArray(object);
						break;
					}
					catch(NullPointerException ex){
						System.out.println("Please, first create a form.");
					}
				case 5: 
					System.out.println("Thanks for use the system!");
					System.exit(0);
			}
		} // while end.
	}
}

import java.util.Scanner;

public class Vector {
	private String name;
	private int age;	

	public Vector (String name, int age){
		this.name = name;
		this.age = age;
	}

	public static void sortArray (Vector[] object){
		for (int i = 4; i >= 0; i --){ // sort array.
			System.out.println(object[i].toString());
		} 
	}

	public static void deleteArray (Vector[] object){
		for (int i = 4; i >= 0; i --){ // delete all arrays.
			object[i] = null;
		} 
	}

	public static void searchArray (Vector[] object){
		Scanner input = new Scanner(System.in);
	
		System.out.printf("Search Name: Please, input the name: ");
		String search = input.next();

		for (int sch = 0; sch < 5; sch ++){ // search array.
			if (search.equals(object[sch].getName())){
				System.out.println(object[sch].toString());
				break;
			}
			else if (sch == 4){
				System.out.println("Sorry, this name was not found.");
			}
		} 
	}

	public String toString(){
		return "Name: "+name+"\nAge: "+age+"";
	}

	public static int product_Numbers(int[] n){
		int number = 1;

		for(int cont = 0; cont < 2; cont++){
			number *= n[cont];
		}
		return number;
	}
	
	// getters.
	public String getName(){
		return this.name;
	}
	public int getAge(){
		return this.age;
	}
}