Eclipse (a Java IDE) - First Steps

(Free Web Tutorial)

by Michael Thomas

In this tutorial you will install Eclipse SDK, create your first Java Project and then create the Java Cert project for the "Free Java Core & Certification Training Web Tutorial".

This tutorial covers:

Eclipse Neon.1 (Neon.1a Release 4.6.1) as of 10/19/2016

Prerequisites

Have a JDK installed.
This tutorial has been tested in the following environment:
Date: 10/19/2016
OS: Win 10
JDK: Java SE 8u111

Objectives

Install Eclipse SDK,
Create your first Java Project
Create a Java Project from an existing source.
(Note: You will download all of the files for the Java Cert project for the "Free Java Core & Certification Training Web Tutorial" and setup a project.)

Terms

IDE - Interactive Development Environment
JDK - Java Development Kit
SDK - Software Development Kit

Eclipse Prerequisite

Java (VM) Settings

Note: I cover setting the "JAVA_HOME" & "Path" variable in my Java JDK Download Install Tutorial
Check #1: JAVA_HOME system variable
Go to the DOS prompt
Type: set JAVA_HOME
Example results:
JAVA_HOME=C:\_data\java\jdk1.8.0_111

Error Notes:
- Error: Environment variable JAVA_HOME not defined
  Fix: set your "JAVA_HOME" "System Variable"
Check #2: java.exe, javaw.exe, javac.exe
Go to the DOS prompt. (ie: C:\).

Type: java.exe -version
Example Results: (MAKE NOTE of the version and bit for Check #3)
java version "1.8.0_111"
Java(TM) SE Runtime Environment (build 1.8.0_111-b14)
Java HotSpot(TM) 64-Bit Server VM (build 25.111-b14, mixed mode)

Type: %JAVA_HOME%\bin\java.exe -version
Example Results: (MAKE NOTE of the version and bit for Check #3)
java version "1.8.0_111"
Java(TM) SE Runtime Environment (build 1.8.0_111-b14)
Java HotSpot(TM) 64-Bit Server VM (build 25.111-b14, mixed mode)

Type: javaw.exe
Example Results:
Returns nothing. No errors either.

Type: javac.exe -fullversion
Example Results:
javac full version "1.8.0_111-b14"

Error Notes:
- Error: The system cannot find the path specified.
  Fix: Modify the "path" "System Variable" to include "%JAVA_HOME%\bin"
Check #3: 32 bit vs 64 bit (Eclipse & Java JDK)
The Eclipse & Java JDK bit (32 vs 64) versions must be the same! (I experienced that one time.)
If you have a 64 bit OS I suggest both being 64 bit.
Notes for finding out the bit version of java.

Here are the two Java commands:
Eclipse Java (system's JRE): java -version
Java JDK: %JAVA_HOME%\bin\java -version

Where is the bit version?
Look at the "Java HotSpot" line.
32 bit: Java HotSpot(TM) Client VM
64 bit: Java HotSpot(TM) 64-Bit Server VM

Eclipse Download

Prerequisites - JRE (Java Runtime Environment)
OPTIONAL Reference: Checksum hash values

Checksum hash values (md5, sha256) are given for each executable file you download so you can verify that the downloaded file has not been modified.
Checksum Hash Tutorial - has reference to online and installed tools you can use to verify the downloads.

Download Eclipse
- www.eclipse.org
  - Download Eclipse Neon.1
  - Optional: Reference Information
    - Older versions of Eclipse:
      http://wiki.eclipse.org/Older_Versions_Of_Eclipse
      http://archive.eclipse.org
    - Eclipse Neon Documentation: http://help.eclipse.org/neon/index.jsp
      See:
      Workbench User Guide
      Java development user guide

Eclipse Install

Install Eclipse
- In Win Explorer, double click on the exe to run the install.
- Select the product "Eclipse IDE for Java Developers"
- Installation Folder:
  C:\_data\eclipse\java-neon - this is my choice that I'll use for this demo.
- Click the "Install" button.
  Click "Accept Now"
  Click "Launch"
- Screen: Select a directory as workspace
- Screen: Welcome
- Close Eclipse - click the X button.
  We will launch it in the next steps.
Launch Eclipse
- Win 10, type "Eclipse" in the "Ask me anything".
  Click the "Eclipse Java Neon" desk app.
  
  (Optionally: Click on the exe: C:\_data\eclipse\java-neon\eclipse\eclipse.exe )
- WARNING: When you launch Eclipse do NOT check "Use this as the default and do not ask again."
  
  You'll soon learn that it is nice to have many workspaces.
  The last workspace you used is the default and you can choose ones in the past with the drop down select.
  - If you do accidentally click the check box here is how you put the option back.
    Eclipse workspace steps:
    Windows, Preferences, expand General, expand "Startup and Shutdown", Workspaces
    Check: Prompt for workspace on startup.
    Choose 10 or your choice for: Number of recent workspaces to remember.
    (Optional: Windows, Preferences, in the box at top type "workspace".)
- Optional: Launch errors.
- Workspace = C:\_data\eclipse\wsMyEclipseTutorial
  (Default for Win7 is: C:\Users\<username>\workspace)
- Click OK.
- Close the "Welcome" Screen by clicking the X. (Note: You can display it at any time: Help, Welcome)
You have installed Eclipse!

Create a Test Java Project

Launch Eclipse and select the workspace:
C:\_data\eclipse\wsMyEclipseTutorial
Close the "Welcome" window by clicking the X button.
Create a test Java Project
- File, New, "Java Project"
- Project name: MyJavaTest
  Check: "Use default location" - should show: C:\_data\eclipse\wsMyEclipseTutorial\MyJavaTest
- JRE
  Use default: Select "Use an execution environment JRE:"
  Note: notice the value: JavaSE-1.8
- Project Layout
  Use default: Select "Create separate folders for sources and class files."
- Click "Next"
  Notice the following subdirectories:
  src
  bin - default output folder (at bottom).
- Click "Finish"
Create a new Java Class
- File, New, Class
- Source Folder: should be defaulted to: "MyJavaTest/src".
- Package: com.michaelthomas.eclipsetutorial
- Project Name: MyApplication
- Modifiers: select "public"
- Superclass: java.lang.Object
- Which method studs would you like to create?
  Check - public static void main(string[] args)
  Check - Inherited abstract methods
- Do you want to add comments?
  Check - Generate comments
- Click "Finish"
- Modify the generated code:
```
/**
 * 
 */
package com.michaelthomas.eclipsetutorial;

/**
 * @author Michael Thomas
 *
 */
public class MyApplication {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		System.out.println("Hello World from an Application.");

	}

}
```
- Save the application with "Ctrl-S".
- Click "Run" the Java applicaton
  Options:
  * Click green play button
  * Click the black down arrow to the right of green play button, "Run As", "Java Application"
  * Click Run tab, "Run As", "Java Application"
  * Press Ctrl-F11
- In the "Console" window at the bottom you should see the following:
  Hello World from an Application.
- Clear the Console area.
  Options:
  * Right click, Clear
  * Click the "Clear Console" icon (Paper with an X in it - in the panel of icons to the top right of the console output.)
- Here is the folder structure & files. View with Win Explorer!
  MyApplication\
  * .classpath
  * .project
  MyApplication\.settings
  * org.eclipse.jdt.core.prefs
  MyApplication\bin\com\michaelthomas\eclipsetutorial
  * MyApplication.class
  MyApplication\src\com\michaelthomas\eclipsetutorial
  * MyApplication.java
- Congratulations - you have created and tested you first Java Application.

Now visit the "Must Know ASAP" section of the "EclipseSurvival Guide" page.

Optional: Uninstall Eclipse (Neon) - How to

"Eclipse Java Neon" does not have an "Uninstall" feature.
Remove "Eclipse Java Neon" Software

Delete the the install directory.
Ex: C:\_data\eclipse\java-neon

Remove "Eclipse Java Neon" from Menu.

In the "Ask me anything" type: Eclipse Java Neon
Right click on the menu item and choose "Open file location"
Backup 1 directory level and delete the directory "Eclipse" or if you have other Eclipse software installed that you want to keep just delete the file named "Eclipse Java Neon"

Location example:
Directory: C:\Users\<YourUserName>\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Eclipse
Filename: Eclipse Java Neon

Optional: Create a Shortcut

Win 7 - Create an entry in "Start"
- Using Windows Explorer, navigate to: c:\eclipse.
- Right click on the file "eclipse.exe" and choose "Create Shortcut".
- Now left click on the file "eclipse.exe - Shortcut" and drag it on top of the Windows "Start" icon in the very bottom left corner of your computer.
  Windows will "pin" it to the "Start" button.
- Note: You can do the same thing to your Desktop.
Win XP - Create an entry in "Start", "All Programs"
- Right click on "Start", choose "Explorer all users",
- Click on "Programs"
- Click "File", "New", "Shortcut"
- For location of item, browse to: C:\eclipse\eclipse.exe
- Click next.
- Name for the shortcut: Eclipse
- Click "Finish"
- Click "Start", "All Programs"
- Click "Eclipse" to launch the program.
Test your shortcut.