Java Syntax

Java is picky about syntax. Each statement ends with a semicolon, blocks use curly braces { }, and names are case-sensitive: Main and main are different.

ExampleJava

public class Main {
  public static void main(String[] args) {
    // This is a single-line comment
    System.out.println("First line");
    /* This is a
       multi-line comment */
    System.out.println("Second line");
  }
}

Output

First line
Second line

By convention class names start with a capital letter (MyClass), while methods and variables start lower case (myMethod). The file name must match the public class name: Main lives in Main.java.

Quick check

How does a Java statement end?

With a periodWith a semicolonWith a colon

Finish the quick check (and any code exercise) to complete this lesson, or mark it done yourself.

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