Question

public int available(Item pItem)

{

if( aInventory.containsKey(pItem))

{

return aInventory.get(pItem);

}

else

{

return 0;

}

}

Java Junit

Write a test suite to test function 'available' in 'inventory' tp ensure 100% statement coverage in 'available' function to ensure 100% statement coverage in 'available' function. do not use the stock function, instead use reflection

Answer 1

Solution:

Please note since the implementation of Item object is not mentioned certain assumptions have been taken which are mentioned as comments.

Please find below the code:

TestClassForAvailableMethod.java

import java.util.HashMap;
import java.util.Map;

import org.junit.Assert;
import org.junit.BeforeClass;
import org.junit.Test;

public class TestClassForAvailableMethod {

  
   Map<Item, Integer> aInventory = null;
   Item pItemObj1 = null;
   Item pItemObj2 = null;
   Item pItemObj3 = null;
  
   /**
   * this method will run before any other
   * test method of this class
   * executes
   */
   @BeforeClass
   public void setUp(){
       aInventory = new HashMap<>();
       pItemObj1 = new Item(); // assuming Item class have a no-arg constructor
       pItemObj2 = new Item(); // assuming Item class have a no-arg constructor
       pItemObj3 = new Item(); // assuming Item class have a no-arg constructor
       aInventory.put(pItemObj1, 1); // inserting first Item object in the aInventory map
       aInventory.put(pItemObj2, 2);// inserting second Item object in the aInventory map
   }

   /**
   * this method tests if the
   * inventory contains the given
   * item and asserts if it returned
   * correct 'value of the corresponding item object
   * in the aInventory' in this case 1
   */
   @Test
   public void testAvailableWithKeyPresent(){
       Assert.assertEquals(1, available(pItemObj1));
   }

   /**
   * this method tests if the
   * inventory contains the given
   * item and asserts if it returned
   * correct result i.e. 0
   */
   @Test
   public void testAvailableWithoutKeyPresent(){
       Assert.assertEquals(0, available(pItemObj3));
   }
}

Answer 2

To achieve 100% statement coverage for the 'available' function using JUnit without using the stock function and using reflection, you can write multiple test cases to cover all possible code paths in the function. Here's an example of how to create a test suite for the 'available' function:

First, ensure you have the necessary imports:

javaCopy codeimport static org.junit.Assert.assertEquals;import java.lang.reflect.Method;

Now, create a test class for the 'available' function:

javaCopy codepublic class InventoryTest {    private Inventory inventory; // Replace 'Inventory' with the actual class name

    @Before
    public void setUp() {        // Create an instance of the 'Inventory' class to test
        inventory = new Inventory(); // Replace 'Inventory' with the actual class name
    }    @Test
    public void testAvailableWithExistingItem() {        // Test when the item exists in the inventory
        // Add the item to the inventory
        Item item = new Item("item1"); // Replace 'Item' with the actual item class
        inventory.aInventory.put(item, 5); // Assuming 'aInventory' is the map storing items and their quantities
        // Call the 'available' function using reflection
        int result = invokeAvailableFunction(item);        // Check if the result matches the expected value
        assertEquals(5, result);
    }    @Test
    public void testAvailableWithNonExistingItem() {        // Test when the item does not exist in the inventory
        // Call the 'available' function using reflection with a non-existing item
        int result = invokeAvailableFunction(new Item("nonExistingItem")); // Replace 'Item' with the actual item class
        // Check if the result matches the expected value (0)
        assertEquals(0, result);
    }    // Helper method to invoke the 'available' function using reflection
    private int invokeAvailableFunction(Item item) {        try {            // Get the 'available' method using reflection
            Method availableMethod = Inventory.class.getDeclaredMethod("available", Item.class); // Replace 'Inventory' with the actual class name
            // Set the method accessible (since it may be private)
            availableMethod.setAccessible(true);            // Invoke the method on the 'inventory' object with the given item parameter
            return (int) availableMethod.invoke(inventory, item);
        } catch (Exception e) {            // Handle any exceptions (e.g., reflection-related or method not found)
            e.printStackTrace();
        }        return -1; // Return a default value or handle error case appropriately
    }
}

In the above test suite, we have two test cases: one for when the item exists in the inventory and another for when the item does not exist. The invokeAvailableFunction method uses reflection to access and invoke the 'available' function on the 'inventory' object.

Ensure that you replace 'Inventory' with the actual class name and 'Item' with the actual item class name in the test suite according to your code implementation.