Writing My First Java Program

This section provides a tutorial example on how to write, compile, and execute the first Java program with JDK 1.8.0.

When JDK is installed on your machine, it provides two commands for you to compile and run Java programs.

Let's try these commands with a very simple Java program. Use NotePad to enter the following Java program into a file called Hello.java:

class Hello {
   public static void main(String[] a) {
      System.out.println("Hello world!"); 	
   }
}

Then compile this program in a command window with the "javac" command:

C:\>\progra~1\java\jdk-10.0.1\bin\javac Hello.java

To execute the program, use the java command:

C:\>\progra~1\java\jdk-10.0.1\bin\java Hello
Hello world!

Congratulations, you have successfully entered, compiled and executed your first Java program.

Last update: 2018.

Table of Contents

 About This JDK Tutorial Book

JDK (Java Development Kit)

 What Is JDK

 Downloading and Installing JDK 10

Writing My First Java Program

 Adding JDK "bin" Directory to Path Setting

 JDK Documentation Installation

 Java Date-Time API

 Date, Time and Calendar Classes

 Date and Time Object and String Conversion

 Number Object and Numeric String Conversion

 Locales, Localization Methods and Resource Bundles

 Calling and Importing Classes Defined in Unnamed Packages

 HashSet, Vector, HashMap and Collection Classes

 Character Set Encoding Classes and Methods

 Character Set Encoding Maps

 Encoding Conversion Programs for Encoded Text Files

 Java Logging

 Socket Network Communication

 Datagram Network Communication

 DOM (Document Object Model) - API for XML Files

 SAX (Simple API for XML)

 DTD (Document Type Definition) - XML Validation

 XSD (XML Schema Definition) - XML Validation

 XSL (Extensible Stylesheet Language)

 Message Digest Algorithm Implementations in JDK

 Private key and Public Key Pair Generation

 PKCS#8/X.509 Private/Public Encoding Standards

 Digital Signature Algorithm and Sample Program

 "keytool" Commands and "keystore" Files

 KeyStore and Certificate Classes

 Secret Key Generation and Management

 Cipher - Encryption and Decryption

 The SSL (Secure Socket Layer) Protocol

 SSL Socket Communication Testing Programs

 SSL Client Authentication

 HTTPS (Hypertext Transfer Protocol Secure)

 Outdated Tutorials

 References

 Full Version in PDF/EPUB