Commit d0235e3

<section xml:id="lets_look_java_program_summary">

<title>Summary &amp; Reading Questions</title>

<p><ol label="1">

<li>

<p>Java programs must be compiled before execution, unlike Python which is interpreted directly.</p>

</li>

<li>

<p>Every Java program must define a <c>class</c>, and all code must be inside that class.</p>

</li>

<li>

<p>Each Java program must include a <c>public static void main(String[] args)</c> method as the entry point.</p>

</li>

<li>

<p>Java enforces that every variable and method must have a clearly defined type, including <c>void</c> for methods that return nothing.</p>

</li>

<li>

<p>Statements in Java must end with a semicolon (<c>;</c>), and whitespace is not syntactically meaningful.</p>

</li>

<li>

<p>Java uses dot notation to access class members, such as <c>System.out.println</c> for output.</p>

</li>

<li>

<p>The <c>static</c> keyword indicates that a method belongs to the class itself, rather than to an instance of the class.</p>

</li>

</ol></p>

<reading-questions xml:id="rqs-hello-java">

<exercise label="hello-java-1">

<statement>

<p>Which of the following must be true of every Java program?</p>

</statement>

<choices>

<choice>

<statement><p>It must contain a method called <c>main()</c> with no parameters.</p></statement>

<feedback><p>No. The main method must include a specific parameter: <c>String[] args</c>.</p></feedback>

</choice>

<choice correct="yes">

<statement><p>It must include a <c>public static void main(String[] args)</c> method inside a class.</p></statement>

<feedback><p>Correct! This is the required entry point for all Java applications.</p></feedback>

</choice>

<choice>

<statement><p>It must be saved with a <c>.exe</c> extension.</p></statement>

<feedback><p>No. Java source files use the <c>.java</c> extension and compile to <c>.class</c>.</p></feedback>

</choice>

<choice>

<statement><p>It must be run using the Python interpreter.</p></statement>

<feedback><p>No. Java uses its own compiler and Java Virtual Machine (JVM).</p></feedback>

</choice>

</choices>

</exercise>

<exercise label="hello-java-2">

<statement>

<p>What is the purpose of the <c>javac</c> command?</p>

</statement>

<choices>

<choice correct="yes">

<statement><p>To compile Java source code into bytecode</p></statement>

<feedback><p>Exactly! <c>javac</c> compiles <c>.java</c> files into <c>.class</c> files.</p></feedback>

</choice>

<choice>

<statement><p>To run a Python program</p></statement>

<feedback><p>No. Python programs are run with the <c>python</c> or <c>python3</c> command.</p></feedback>

</choice>

<choice>

<statement><p>To debug Java programs</p></statement>

<feedback><p>No. <c>javac</c> only compiles code. Debugging is a separate process.</p></feedback>

</choice>

<choice>

<statement><p>To edit Java source files</p></statement>

<feedback><p>No. You use a text editor or IDE to edit Java files.</p></feedback>

</choice>

</choices>

</exercise>

<exercise label="hello-java-3">

<statement>

<p>What symbol does Java use to indicate the end of a statement?</p>

</statement>

<choices>

<choice>

<statement><p><c>#</c></p>

</statement>

<feedback>

<p>No. <c>#</c> is used for comments in Python, not for statement termination.</p>

</feedback>

</choice>

<choice correct="yes">

<statement><p><c>;</c></p>

</statement>

<feedback>

<p>Correct! Java uses semicolons to mark the end of a statement.</p>

</feedback>

</choice>

<choice>

<statement><p><c>.</c></p>

</statement>

<feedback>

<p>No. <c>.</c> is used for dot notation, not to end a statement.</p>

</feedback>

</choice>

<choice>

<statement><p><c>}</c></p>

</statement>

<feedback>

<p>No. <c>}</c> is used to close code blocks.</p>

</feedback>

</choice>

</choices>

</exercise>

</reading-questions>

</section>