Java Tools Tutorials - Herong's Tutorial Examples

By Herong Yang

This tutorial book based on notes and sample codes collected by the author while he was learning Java tools himself. Topics includes: 'java/javaw' Launcher, 'javac' Compiler, 'javadoc' Document Generator, 'javap' Class File Disassembler, 'jar/jarsigner' Archive Tool, 'jconsole' Console, 'jdb' Debugger, 'jdeps' Dependency Analyzer, 'jdeprscan' Deprecated API Scanner, 'jhat' Heap Analysis Tool, 'jlink' JRE Linker, 'jhsdb' HotSpot Debugger, 'jmap' Memory Dumper, 'jmc' Mission Control, 'jpackage' Binary Package Builder, 'jrunscript' Script Shell, 'jstack' Stack Dumper, 'jstat' Statistics, 'jstatd' Statistics Daemon, 'jvisualvm' Visual VM, 'jwebserver' Web Server, 'keytool' Keystore Tool, 'serialver' serialVersionUID generator. Updated in 2024 (Version v6.24) with minor updates.

• Language: English
• Publisher: Lulu.com
• Release date: Mar 1, 2019
• ISBN: 9780359437597

Book preview

The Front Cover

Java Tools Tutorials

- Herong's Tutorial Examples

Icon

v6.24, 2024

Herong Yang

Copyright © 2005-2024 Herong Yang. All rights reserved.

ISBN: 978-0-359-43759-7

This tutorial book based on notes and sample codes collected by the author while he was learning Java tools himself. Topics includes: 'java/javaw' Launcher, 'javac' Compiler, 'javadoc' Document Generator, 'javap' Class File Disassembler, 'jar/jarsigner' Archive Tool, 'jconsole' Console, 'jdb' Debugger, 'jdeps' Dependency Analyzer, 'jdeprscan' Deprecated API Scanner, 'jhat' Heap Analysis Tool, 'jlink' JRE Linker, 'jhsdb' HotSpot Debugger, 'jmap' Memory Dumper, 'jmc' Mission Control, 'jpackage' Binary Package Builder, 'jrunscript' Script Shell, 'jstack' Stack Dumper, 'jstat' Statistics, 'jstatd' Statistics Daemon, 'jvisualvm' Visual VM, 'jwebserver' Web Server, 'keytool' Keystore Tool, 'serialver' serialVersionUID generator. Updated in 2024 (Version v6.24) with minor updates.

Table of Contents

About This Book

Java Tools Terminology

Java Tools Included in JDK

Installing Latest JDK on macOS

Installing Latest JDK on Windows

Adding JDK bin Direcotry to Path Setting

Testing JDK Installation

Listing Java Tools in JDK

javac - The Java Program Compiler

javac - Java Compilation Command and Options

Compiling Hello.java - My First Java Program

javac -classpath - Specifying Class Path

javac -verbose - Printing Compilation Details

javac -sourcepath - Specifying Source Path

javac -d - Specifying Output Directory

Two Types of import Statements

import Statements Processed by javac

javac -g - Controlling Debugging Information

javac --module - Compiling Entire Module

javac -X - Specifying Non-Standard Options

java - The Java Program Launcher

java - Program Launching Command and Options

Launching Hello.java - My First Java Program

java -classpath - Specifying Class Path

java -jar - Specifying Executable JAR File

java -X - Specifying Non-Standard Options

java --list-modules - Listing Modules in JDK

java --describe-module - Printing Module Definition

java --module - Launching Program from Module

java --module - Launching Program from Module JAR

javaw - Launching Java Programs without Console

jar - The JAR File Tool

JAR - Java Archive File Format

jar - JAR File Tool Command and Options

jar --create - Creating New JAR File

jar --list - Listing Files in JAR File

jar --extract - Extracting Files from JAR File

Managing JAR Files with WinZIP

META-INF/MANIFEST.MF - JAR Manifest File

Adding META-INF/MANIFEST.MF to JAR Files

jar -C - Changing Input Directory

Using JAR Files in Java Class Paths

jar --update - Updating Class Files in JAR

jar --main-class - Making JAR File Executable

Creating Module JAR File

jar --module-version - Updating Module Version in JAR

jlink - The JRE Linker

jlink - What Is It

jlink --add-modules java.base - Build Base JRE

Running Java Programs with New JRE

Building Application Modules into New JRE

jlink --launcher - Generating Launching Scripts

jmod - The JMOD File Tool

JMOD - Java Module File Format

jmod - JMOD File Tool Command

jmod create --class-path - Create New JMOD File

jmod describe/list - Get Info from JMOD File

Creating JMOD File from JAR Files

jmod create --cmds|config|libs... - Packaging Other Files

jmod extract --dir - Extracting Files

javac --add-modules - Compiling with Supporting JMOD Files

jlink --add-modules - Building JRE from JMOD Files

jimage - The JIMAGE File Tool

JIMAGE - Java Image File Format

jimage - JIMAGE File Tool Command

jimage info|list - Listing JIMAGE Entries

jimage extract - Extracting JIMAGE File Entries

Java File Types and Related Tools

jpackage - Binary Package Builder

jpackage - What Is It

jpackage -t dmg - Package for macOS

jpackage -t pkg - Package for macOS

jpackage -t msi - Package for Windows

javadoc - The Java Document Generator

javadoc - Document Generator Command and Options

Hello.java API Document

HelloDocumented.java - javadoc-Style Comments

Generate API Document for Java Package

jdeps - The Java Class Dependency Analyzer

jdeps - Class Dependency Analyzer Command

jdeps class_file - Dependencies of Class File

jdeps -verbose - Class Level Dependencies of Class File

jdeps jar_file - Dependencies of JAR File

jdeps --inverse --require ... - Reverse Dependencies

jdeprscan - The Java Deprecated API Scanner

jdeprscan - Deprecated API Scanner Command

jdeprscan jar_file - Deprecated API of Class File

jdeprscan jar_file - Deprecated API of JAR File

jdeprscan --release X - Deprecated API as of Release X

jdeprscan --list - List All Deprecated APIs

jdb - The Java Debugger

jdb - Java Debugger Command and Options

Starting a Debugging Session with jdb

Debugging Applications with Separate jdb Sessions

Debugging Java Applications Remotely

Listing Debugging Commands with help Command

PrimeNumberSeeker.java - Multi-Thread Sample Program

Starting Debugging Session on a Multi-Thread Application

Stepping through Statements of a Child Thread

Checking Variable Values in a Debugging Session

Debugging the Main Thread of a Multi-Thread Application

Switching Execution Threads in a Debugging Session

Suspending Main Thread to Debug Child Thread

jcmd - The JVM Diagnostic Tool

jcmd - JVM Diagnostic Tool Command

jcmd 0 help - Listing JVM Diagnostic Commands

jcmd 0 VM.* - Running VM Diagnostic Commands

jcmd 0 GC.* - Running GC Diagnostic Commands

jcmd 0 Thread.print - Generating Thread Dump

jconsole - Java Monitoring and Management Console

JMX Technology and jconsole Tool

jconsole - Command Options and Connection Window

com.sun.management.jmxremote - JMX Agent for Local Connection

jconsole - Connecting to a Local JMX Agent

com.sun.management.jmxremote.port - JMX Agent for Remote Connection

jconsole - Connecting to a Remote JMX Agent

jstat - JVM Statistics Monitoring Tool

jps - JVM Process Status Tool

jps - Listing JVM Processes on the Local Machine

jstatd - JVM Remote Monitoring Server

Starting jstatd with a Security Policy File

Connecting jps to Remote jstatd

jstat - Command Options and Parameters

Garbage Collection Testing Program

jstat -gcutil - Garbage Collection Statistics

jstat - Accessing Remote JVM Processes

JVM Troubleshooting Tools

JVM Troubleshooting Tools in JDK

jinfo - VM Option Value Checker

jinfo - Changing HotSpot VM Option

jstack - Stack Tracer to Generate Thread Dump

What Is a Thread Dump?

Java Thread Deadlock Demo Program

jstack - Detecting Java Thread Deadlocks

jmap - JVM Heap Dump Tool

Printing Histogram of Java Object Heap

jmap - Generating Heap Dump File

jhat - Java Heap Analysis Tool

jhat - Starting Web Server on a Heap Dump File

Listing Instance Counts of All Classes

Browsing Object Instance Values

Object Query Language (OQL)

Searching for Instances with OQL Statements

jhsdb - The Java HotSpot Debugger

jhsdb - HotSpot Debugger Command

jhsdb hsdb - HotSpot Debugger in GUI Mode

jhsdb hsdb - Inspecting main Thread

jhsdb hsdb - Viewing Stack Memory Map

jhsdb clhsdb - HotSpot Debugger in Command Line

jvisualvm (Java VisualVM) - JVM Visual Tool

What Is jvisualvm (Java VisualVM)?

jvisualvm Command to Open Dump Files or Connections

Connecting Java VisualVM to a Local JVM Process

Monitoring Usages of CPU, Heap, Classes and Threads

Monitoring Thread Status as Timeline

Taking Thread Dump to See Thread Stack Traces

Taking Heap Dump to See Memory Usages

Viewing a Heap Dump File

Connecting to Remote JVM Processes

Available Plugins and Installation

Installing Visual GC Plugin

jmc - Java Mission Control

jmc (Java Mission Control) - What Is It

Launching jmc (Java Mission Control)

jmc - JMX Console via MBean Server

MBean Browser on jmc JMX Console

Monitoring Trigers on jmc JMX Console

javap - The Java Class File Disassembler

javap - Java Disassembler Command and Options

javap - Listing Public Variables and Methods

javap -private - Listing Private Variables and Methods

javap -c -private - Disassembling Java Bytecode Class

Looking Up Method Signature with javap Command

keytool - Public Key Certificate Tool

Certificates and Certificate Chains

keystore - Public Key Certificate Storage File

keytool - keystore File Management Commands

Generating Key Pairs and Self-Signed Certificates

Exporting and Import Certificates

Cloning Certificates with New Identities

keytool -importkeystore - Converting Keystore Type

jarsigner - JAR File Signer

jarsigner - What Is It

What Is Digital Signature

keytool -genkeypair - Self-Signed Certificate

jarsigner - Signing JAR File

jarsigner -verify - Verifying Signed JAR

jarsigner -verify -keystore ... - Trusted Certificate

jarsigner -verify -verbose -certs - Signature Details

*.SF/*.DSA - Signature Files in Signed JAR

jshell - Java Language Shell

jshell - What Is It

jshell - Entering Expressions and Statements

jshell> /save - Saving Code Snippet

jshell> /edit - Editing Code Snippet

jrunscript - Script Code Shell

jrunscript - What Is It

jrunscript - Run JavaScript Interactively

jrunscript -f - Run JavaScript in Batch Mode

Miscellaneous Tools

serialver - serialVersionUID Generator

jaotc - Java Ahead-Of-Time Compiler

jwebserver - Java Web Server

native2ascii - Native-to-ASCII Encoding Converter

native2ascii - Encoding Converter Command and Options

javac - Using CP1252 to Process Source File

native2ascii -encoding - UTF-8 to uXXXX Conversion

Setting UTF-8 Encoding in PrintStream

Converting uXXXX Sequences Back with -reverse Option

JAB (Java Access Bridge) for Windows

What Is JAB (Java Access Bridge)

Java GUI Test Program

jaccesswalker - GUI Component Tree Browser

jaccessinspector - Accessible Information Examiner

Archived Tutorials

Installing JDK 15 on macOS

Archived: Installing JDK 12 on Windows

Archived: Installing JDK 10 on Windows

Archived: Downloading and Installing Java 8

Archived: Downloading and Installing J2SE 1.6.0 on Windows

Archived: JDK 1.6 keytool - keystore File Tool

Archived: Downloading and Installing J2SE 1.5.0 on Windows

Archived: JDK 1.5 keytool - keystore File Tool

References

Keywords: Java, Tools, Compiler, Debugger, Monitor

Java Tools Tutorials - Herong's Tutorial Examples

∟ About This Book

This section provides some detailed information about this book - Java Tools Tutorials - Herong's Tutorial Examples.

Title: Java Tools Tutorials - Herong's Tutorial Examples

Author: Herong Yang - Contact by email via [e-mail].

Category: Programming

Version/Edition: v6.24, 2024

Number of pages in PDF format: 376

Description: This tutorial book based on notes and sample codes collected by the author while he was learning Java tools himself. Topics includes: 'java/javaw' Launcher, 'javac' Compiler, 'javadoc' Document Generator, 'javap' Class File Disassembler, 'jar/jarsigner' Archive Tool, 'jconsole' Console, 'jdb' Debugger, 'jdeps' Dependency Analyzer, 'jdeprscan' Deprecated API Scanner, 'jhat' Heap Analysis Tool, 'jlink' JRE Linker, 'jhsdb' HotSpot Debugger, 'jmap' Memory Dumper, 'jmc' Mission Control, 'jpackage' Binary Package Builder, 'jrunscript' Script Shell, 'jstack' Stack Dumper, 'jstat' Statistics, 'jstatd' Statistics Daemon, 'jvisualvm' Visual VM, 'jwebserver' Web Server, 'keytool' Keystore Tool, 'serialver' serialVersionUID generator. Updated in 2024 (Version v6.24) with minor updates.

Keywords: java, javac, javaw, jar, jarsigner, javap, jconsole, jdb, jdeps, jdeprscan, jhsdb, jhat, jlink, jmap, jmc, jps, jshell, jstack, jstat, jstatd, jvisualvm, keytool, native2ascii.

Copyright:

This book is under Copyright © 2005-2024 Herong Yang. All rights reserved.

Material in this book may not be published, broadcasted, rewritten or redistributed in any form.

The example codes is provided as-is, with no warranty of any kind.

Revision history:

Version v6.24, 2024. Minor updates.

Version v6.23, 2023. Updated with JDK 20.

Version v6.22, 2022. Updated with JDK 17.

Version v6.10, 2018. Added more tutorials on jmod and jlink.

Version v6.00, 2018. Updated with JDK 10.

Version v5.00, 2014. Updated with JDK 8.

Version v1.00, 2005. First release.

Web version: https://www.herongyang.com/Java-Tools - Provides free sample chapters, latest updates and readers' comments. The Web version of this book has been viewed a total of:

2,441,549 times as of December 2023.

2,281,357 times as of December 2022.

2,137,746 times as of December 2021.

1,992,683 times as of December 2020.

1,866,739 times as of December 2019.

1,760,030 times as of December 2018.

1,666,610 times as of December 2017.

1,560,981 times as of December 2016.

1,426,899 times as of December 2015.

1,234,950 times as of December 2014.

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631,149 times as of December 2011.

395,375 times as of December 2010.

208,671 times as of December 2009.

PDF/EPUB version: https://www.herongyang.com/Java-Tools/PDF-Full-Version.html - Provides information on how to obtain the full version of this book in PDF, EPUB, or other format.

Java Tools Tutorials - Herong's Tutorial Examples

∟ Java Tools Terminology

This section provides quick descriptions of terms related to Java tools.

Certificate: A digitally signed statement from the issuer saying that the public key of the subject has some specific value.

Certificate Chain: A series of certificates that one certificate signs the public key of the issuer of the next certificate. Usually the top certificate (the first certificate) is self-signed, where issuer signed its own public key.

jabswitch: A Windows command to enable or disable the Java Access Bridge.

jaccessinspector: A Windows GUI tool to examine accessible information about objects of a Java GUI application.

jaccesswalker: A Windows GUI tool to navigate through the component trees of a Java GUI application.

JAR (Java ARchive): A platform-independent file format that aggregates many files into one. Multiple Java applets and their requisite components (.class files, images and sounds) can be bundled in a JAR file and subsequently downloaded to a browser in a single HTTP transaction, greatly improving the download speed.

jar: The JAR manager - A command line tool for managing JAR files.

jarsigner: The JAR Signer - A command line tool for signing JAR files and verifying signed JAR files.

java: The Java launcher - A command line tool to launch Java applications.

javac: The Java compiler - A command line tool to compile Java source files.

javap: The Java Class File Disassembler - A command line tool that reads Java bytecode class files and disassembles them.

jconsole: A graphical user interface tool that enables you to monitor and manage Java applications and virtual machines on a local or remote machine using the JMX technology.

jdb: The Java Debugger - A command line tool to debug Java applications.

jdeps: The Java Class Dependency Analyzer - A command line tool to show package level and class level dependencies.

JDI (Java Debug Interface): A high level Java API providing information useful for debuggers and similar systems needing access to the running state of a (usually remote) virtual machine.

JDK (Java Development Kit): A development environment for building software applications and software components using the Java programming language.

jhat (discontinued since JDK 9) - Heap Dump Browser: Starts a Web server on a Java heap dump file (eg, produced by jmap -dump), allowing the heap to be browsed.

jinfo: Prints configuration information for a given JVM process or a Java core file on the local machine or on a remote machine through a debug server.

jlink - JRE Linker: Assembles and optimizes a set of modules and their dependencies into a custom JRE.

jmap - Memory Map: Prints shared object memory maps or heap memory details of a given JVM process or a Java core file on the local machine or on a remote machine through a debug server.

jmc - Java Mission Control: Invokes a GUI tool suite for managing, monitoring, profiling, and troubleshooting your Java applications. When first installed, Java Mission Control consists of the JMX Console and the Java Flight Recorder.

JMX (Java Management Extensions): A Java standard API for management and monitoring of resources such as applications, devices, services, and the Java virtual machine. The JMX technology was developed through the Java Community Process (JCP) as Java Specification Request (JSR) 3, Java Management Extensions, and JSR 160, JMX Remote API.

JPDA (Java Platform Debugger Architecture): An infrastructure that allows user to build end-user debugger applications. It includes the following three-layered APIs:

Java Debug Interface (JDI), a high-level Java programming language interface, including support for remote debugging;

Java Debug Wire Protocol (JDWP), which defines the format of information and requests transferred between the debugging process and the debugger front end;

The JVM(TM) Tools Interface, JVM TI. This is a low-level native interface that defines the services a Java virtual machine provides for tools, including debugging. JVM TI is new in J2SE 5.0 and replaces JVMDI and JVMPI, both of which are deprecated and will be removed in a future release.

jps - Java Process Status: A new Java tool that lists all JVM processes on the local machine or a remote machine. jps tool is distributed as part of the JDK package and represented by the \Progra~1\java\jdk*\bin\jps.exe program file. jps can be executed with the following syntax:

jrunscript - Script Code Shell: Runs script code in JavaScript or other languages interactively or in batch mode.

jsadebugd - Serviceability Agent Debug Daemon: Attaches to a JVM process or a Java core file and acts as a debug server for remote tools to connect.

jshell - Java Shell: Provides an interactive shell for evaluating Java declarations, expressions, and statements.

jstack - Stack Trace: Prints a stack trace of threads for a given JVM process or a Java core file on the local machine or on a remote machine through a debug server.

jstat: A JVM statistics monitoring tool that displays performance statistics of a given JVM process with a specified sampling interval. jstat tool is distributed as part of the JDK package and represented by the \Progra~1\java\jdk*\bin\jstat.exe program file. jstat can be executed with the following syntax:

jstatd: A server that allows JVM monitoring tools like jps and jstat to access JVM processes from a remote machine. jstatd tool is distributed as part of the JDK package and represented by the \Progra~1\java\jdk*\bin\jstatd.exe program file. jstatd can be executed with the following syntax:

jvisualvm - Java VisualVM: A visual interface for viewing detailed information about Java applications while they are running on a Java Virtual Machine (JVM), and for troubleshooting and profiling these applications. Java VisualVM federates previously standalone tools like JConsole, jstat, jinfo, jstack, and jmap to obtain data from the JVM software, then re-organizes and presents the information graphically, to enable you to view different data about multiple Java applications uniformly, whether they are running locally or on remote machines.

JVM (Java Virtual Machine): A software that simulates a central process unit (Virtual Machine) to run compiled Java code.

keystore: A database used by JDK keytool command and KeyStore class to store your own private keys, and public key certificates you received from someone else.

keytool: A command line tool introduced in JDK 1.2 to manage keys and certificates using keystore. keytool replaces the same functions offered by javakey in JDK 1.1.

native2ascii: Native-to-ASCII Encoding Converter - A command line tool that reads a text file stored in a non-ASCII encoding and converts it to an ASCII text file. All non-ASCII characters will be converted into \uXXXX sequences, where dddd is the Unicode code value of the non-ASCII character.

serialver: A command line tool that can be used to generate a unique serialVersionUID value for any given serializable Java class.

ZIP: A file format is a popular data compression and archival format. A ZIP file contains one or more files that have been compressed or stored.

Java Tools Tutorials - Herong's Tutorial Examples

∟ Java Tools Included in JDK

This chapter provides tutorial notes on Java tools included in the Oracle JDK package. Topics include downloading and installing the latest JDK version on Windows; using 'javac' and 'java' tools to compile and run Java program; listing Java tools in the 'bin' sub-directory of Java home directory.

Installing Latest JDK on macOS

Installing Latest JDK on Windows

Adding JDK bin Direcotry to Path Setting

Testing JDK Installation

Listing Java Tools in JDK

Takeaways:

Installation of Oracle JDK package is easy.

There are about 30 to 50 Java related tools included in the bin directory in different versions of Oracle JDK packages!

Adding JDK bin directory to path environment variable lets me run Java tools without typing the directory path.

Java Tools Tutorials - Herong's Tutorial Examples

∟ Java Tools Included in JDK

∟ Installing Latest JDK on macOS

This section provides a tutorial example on how to download and install the latest version JDK, which includes some nice Java tools, on a macOS system.

As a Java developer kit, the Oracle JDK package includes a number of nice Java tools.

Here is what I did to download and install JDK 20, also called Java SE 20, on my macOS computer.

1. Go to Oracle Java SE download website at oracle.com/technetwork/java/javase/downloads.

2. Click JDK 20 > macOS tab.

3. Click on the jdk-20_macos-x64_bin.dmg link in the x64 DMG Installer line to download the installation file to your Downloads directory.

4. Double-click on the jdk-20_macos-x64_bin.dmg file to install it.

To test the installation, open a command window to try the java command.

herong$ java -version

java version 20.0.1 2023-04-18

Java(TM) SE Runtime Environment (build 20.0.1+9-29)

Java HotSpot(TM) 64-Bit Server VM (build 20.0.1+9-29, mixed mode, sharing)

Cool, I have successfully installed JDK 20 on my macOS computer!

Java Tools Tutorials - Herong's Tutorial Examples

∟ Java Tools Included in JDK

∟ Installing Latest JDK on Windows

This section provides a tutorial example on how to download and install the latest version JDK, which includes some nice Java tools, on a Windows system.

As a Java developer kit, the Oracle JDK package includes a number of nice Java tools.

Here is what I did to download and install JDK 17, also called Java SE 17, on my Windows computer.

Open the Java SE Download page with this URL: https://www.oracle.com/java/technologies/downloads/.

Click the Windows tab under the Java SE Development Kit 17.0.1 downloads. You will see a new page with a list of different download files of JDK 17.

Click the hyper link of https://download.oracle.com/java/17/latest/jdk-17_windows-x64_bin.exe, next to x64 Installer 152 MB.

Save jdk-17_windows-x64_bin.exe to a temporary directory.

Double-click on jdk-17_windows-x64_bin.exe to start the installation wizard.

The installation wizard will guide you to finish the installation.

To test the installation, open a command window to try the java command. If you are getting the following output, your installation is good:

herong> \progra~1\java\jdk-17.0.1\bin\java -version

 

java version 17.0.1 2021-10-19 LTS

Java(TM) SE Runtime Environment (build 17.0.1+12-LTS-39)

Java HotSpot(TM) 64-Bit Server VM

  (build 17.0.1+12-LTS-39, mixed mode, sharing)

Cool, I have successfully installed JDK 17 on my Windows computer!

Java Tools Tutorials - Herong's Tutorial Examples

∟ Java Tools Included in JDK

∟ Adding JDK bin Direcotry to Path Setting

This section provides a tutorial on how to add JDK 'bin' directory to the 'path' system envirnoment variable.

In order to run Java tools by typing their program file name without the directory path name, I updated the path environment variable on my Windows computer:

Open Control Panel > System and Security > System.

Click Advanced system settings.

Click Environment Variables.

Select System variables > Path and click Edit.

Add C:\Progra~1\java\jdk-17.0.1\bin to the beginning of the current path list.

Click OK to save the change.

Then I ran the echo %path% command in a new command window to confirm the change:

herong> echo %path%

 

C:\Progra~1\java\jdk-17.0.1\bin;...

Now I should be able to run Java tool commands without the directory path name:

herong> java -version

 

java version 17.0.1 2021-10-19 LTS

Java(TM) SE Runtime Environment (build 17.0.1+12-LTS-39)

Java HotSpot(TM) 64-Bit Server VM

  (build 17.0.1+12-LTS-39, mixed mode, sharing)

 

herong> javac hello.java

 

herong> java Hello

Hello world!

Now I am ready to play with Java tools included in Oracle JDK package!

Adding JDK bin Direcotry to Path Setting

Adding JDK bin Direcotry to Path Setting

You can also set a new environment variable called java_home to avoid typing the full path name to access Java tool program