Summary  
This chapter explains how to use System.out.print() and System.out.println() to display text output and control when new lines are started in Java.  

General domain of usage  
Interactive command-line applications

Java provides two main ways to display output on the screen: `print()` and `println()`. While both are used to print text, the key difference is how they handle moving to a new line.

The most commonly used method is `System.out.println()`. It prints the text and automatically moves the cursor to the next line. This makes the output clean and easy to read, especially when printing multiple lines.

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On the other hand, `System.out.print()` prints text but does not move to a new line. Instead, everything continues on the same line.

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This difference becomes very important when you start controlling how your output is formatted. In most beginner cases, `println()` is preferred because it automatically organizes output in a readable way.

package com.example;

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

import java.io.ByteArrayOutputStream;
import java.io.PrintStream;
import java.util.regex.Pattern;
import java.util.regex.Matcher;

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

public class MainTest {

    @Test
    @DisplayName("main() prints Hello World!")
    void testPrintsHelloWorldFlexible() {
        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();

        Pattern pattern = Pattern.compile("hello\\\s+world\\\s*!?", Pattern.CASE_INSENSITIVE);
        assertTrue(pattern.matcher(output).find(), "Actual output: " + output);
    }
}

MainTest.java

Dive into the fundamentals of Java by learning the core concepts that power modern applications. Explore variables, data types, operators, conditionals, and strings while building a strong foundation in programming. Through practical examples and hands-on challenges, you'll develop the skills needed to write, understand, and troubleshoot Java code with confidence.

Discover how to begin your Java journey by learning what Java is, where it is used, and how Java programs are structured. Understand how to print output, write comments, and build the foundation needed for all future programming concepts.

Master the skills needed to store, manage, and work with data in Java. Learn how variables, constants, data types, operators, and type casting work, and apply these concepts through practical coding exercises and real-world examples.

Explore the essentials of decision-making in Java by working with comparison and logical operators, conditional statements, and switch expressions. Learn how programs evaluate conditions, make choices, and respond to different situations through practical examples and challenges.

Dive into the fundamentals of working with text in Java. Learn how strings are created and manipulated, explore formatting and comparison techniques, validate user input, extract useful information from text, and apply these skills in realistic programming scenarios.

Printing Output

Solution