Introduction to Java - Vocabulary Flashcards

Vocabulary flashcards covering core Java concepts, the JVM, JRE/JDK, keywords, syntax, and basic program structure from the lecture notes.

Java

Free-to-use, high-level, object-oriented programming language (1995) that runs on the Java Virtual Machine and supports Write Once, Run Anywhere.

Java Runtime Environment (JRE)

Provides the libraries and runtime required to run Java programs.

Java Development Kit (JDK)

Includes the JRE plus tools for developing, compiling, and debugging Java applications.

Java Virtual Machine

Run-time engine that translates Java bytecode into machine code and executes it.

Bytecode

Intermediate, platform-independent code produced by the Java compiler from .java source files.

Write Once, Run Anywhere (WORA)

Java's platform independence concept: code compiled once can run on any underlying platform with a JVM.

Application Programming Interface (API)

Pre-written Java classes and methods that provide reusable functionality.

Java Keywords

Reserved words recognized by the Java compiler; Java has about 50 keywords.

Identifier

Name given to a program component (class, method, or variable); rules include starting with a letter, underscore, or dollar sign; no whitespace and case-sensitive; cannot be a reserved word or true/false/null.

Class

The basic unit of a Java program; blueprint for objects that contains data members and methods.

Skeleton

A simple Java program example used to illustrate structure, typically showing a class with a main method and a print statement.

Main Method

The entry point of a Java application; declared as public static void main(String[] args).

args

Parameter to the main method; an array of Strings that stores command-line arguments.

System.out.println

Java statement that prints output to the console.

Literal String

A sequence of characters enclosed in double quotes used as a constant in Java.

Comment

Non-executable text in code; single-line comments start with // and multi-line comments use /* … */.

Braces

Opening { and closing } symbols that define blocks of code or data; must be matched.

Notepad .java extension

Saving a Java source file with the .java extension (e.g., Demo.java) so it can be compiled.

javac

Java compiler command used to compile .java source files into bytecode (.class files).

java (command)

Java interpreter command used to run compiled Java bytecode (.class files).