package com.example;

import static org.junit.jupiter.api.Assertions.assertEquals;

import java.io.ByteArrayOutputStream;
import java.io.PrintStream;

import org.junit.jupiter.api.DisplayName;
import org.junit.jupiter.api.Test;

public class MainTest {
    @Test
    @DisplayName("sumStringNumbers returns correct sum for normal input")
    void testSumStringNumbersCorrectSum() {
        String[] numbers = {"10", "20", "30", "40"};
        int result = Main.sumStringNumbers(numbers);
        assertEquals(100, result, "sumStringNumbers should return 100 for input {10,20,30,40}");
    }

    @Test
    @DisplayName("sumStringNumbers returns 0 for empty array")
    void testSumStringNumbersEmptyArray() {
        String[] numbers = {};
        int result = Main.sumStringNumbers(numbers);
        assertEquals(0, result, "sumStringNumbers should return 0 for empty array");
    }

    @Test
    @DisplayName("main() prints the correct sum output")
    void testMainPrintsSum() {
        ByteArrayOutputStream outContent = new ByteArrayOutputStream();
        PrintStream originalOut = System.out;
        System.setOut(new PrintStream(outContent));

        Main.main(new String[]{});

        System.setOut(originalOut);

        String output = outContent.toString().trim();
        assertEquals("The sum is: 100", output, "Expected output: The sum is: 100, but got: " + output);
    }
}


MainTest.java

A comprehensive course on Java data types, covering primitives, reference types, type conversion, and practical applications. Designed for learners with basic Java syntax knowledge.

Explore Java's built-in primitive data types, their properties, and how to use them effectively.

Delve into Java's reference types, focusing on Strings and arrays, and how they differ from primitives.

Learn about type casting, automatic conversions, and the use of wrapper classes for primitives.

Challenge: Using Wrapper Classes

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