What is programming?
Why Java?
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How Java code runs
Your code (.java) → Compiler → Bytecode (.class) → JVM → Machine executes it
Your first Java program
java
public class HelloWorld {
public static void main(String[] args) {
System.out.println("Hello, World!");
}
}
Printing output
java
System.out.println("Hello"); // prints "Hello" and moves to NEXT line
System.out.print("Hello"); // prints "Hello" and stays on SAME line
java
System.out.print("AP ");
System.out.print("CS ");
System.out.println("A");
System.out.println("is awesome!");
AP CS A
is awesome!
Comments
java
// This is a single-line comment
/* This is a
multi-line comment */
/** This is a Javadoc comment
* used for documentation */
Key rules of Java syntax
Types of errors
AP Exam Tips
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Common Mistakes
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