Purpose. Why use Java? Installing the Software. Java

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1 Purpose I am providing instructions for those that want to follow along the progress and missteps of Project BrainyCode. Going forward we will just refer to the project a JGG for Java Game Generator (I will just pronounce it as JIG). JGG is a software application that provides users a drag and drop environment to build Java 2D games. In addition, for those that will be following along and learning Java or already know Java JGG will be easily extendable to allow adding features and capabilities not in the original engine. The goal will be to use JGG to teach young kids how to create games and learn Java programming while having fun. I will be periodically posting on this web site ( all the knowledge and information you will need to build your own Java applications especially if you too want to build your own game engine. Why use Java? I elected to use the Java programming language for JGG because it is a cross-platform development tool. You should be able to take create and run JGG and any Java generated applications on many different operating system platforms Windows, Linux or Macintosh. I will be taking a Windows focus with screen shots and instructions since that shall be my primary platform while JGG is being developed. Installing the Software Java If you plan on learning Java or setting your machine for the first time to compile and run Java programs the first thing you will need is the Java development platform. You can obtain it from Oracle by performing a Bing 1 search for Java SDK. There are two different types of packages you can download: Java Runtime Environment (JRE) Java Development Kit (JDK) The JRE contains all the software you will need to run java applets and applications. Java Applets are simple Java programs that run from the browser. Visit to see examples of some simple applets. If you don t see anything it could be that either you need to configure your browser to allow execution of applets or you may not have (unlikely) the JRE installed on your machine. If you are looking to be a software developer than I highly recommend that you install the JDK. In addition, I also highly recommend for web browsers Firefox or Google Chrome. If you have Microsoft windows operating system do the following: 1 currently my favorite search engine. I highly recommend it for the daily cool images it features.

2 1. Open Windows Explorer 2. Navigate to Computer C:\Program Files\Java. You will see a list of jre s or jdk s on your system. Figure 1 - Checking the versions of Java jre or jdk installed on machine. To get the latest jdk perform the following steps: 1. Open a browser to your favorite search engine and enter Java JDK download 2. Download and install the latest (at this time it is jdk-7u5-windows-i586.exe, for Windows XP and Vista that I use). 3. Run the installation file. You will be prompted through setup screens. Select the defaults.

3 Figure 2 - Dialog box for installing Java SE Development Kit Setup the PATH 1. Open Control Panel

4 Figure 3 - Windows Control Panel 2. Double click on System icon 3. Click on Advanced System Settings Figure 4 - Control Panels Systems Dialog box

5 4. Click on Environment variables button Figure 5 - "System Properties" dialog screen Figure 6 - Environment variable dialog box 5. Scroll down the System variables list until you get to Path variable name

6 Figure 7 - Selecting "Path" variable name 6. Click on Edit.. button Double check the new subdirectory created from the existing or current installation of Java Figure 8 - Directory structure on machine

7 The directory root for me is C:\Program Files\Java\jdk1.7.0_0_05\bin The jdk1.7.0_0_05 will certainly be different for you. Enter the entire string at the start of the edit window followed by a semicolon ; Figure 9 - Entering java directory to the path 7. Click OK button 8. Click OK on Environment Variables window 9. Click OK on Systems Properties dialog 10. Close Systems window. Test Java Installation 1. Open command prompt window 2. Enter: java version Figure 10 - Command Prompt window

8 Figure 11 - Determining java version It should display the version of the Java JDK you just installed. On Your Own I also recommend that you make sure that there is an environment variable set for JAVA_HOME. Follow the same steps but this time update (if already there) or create a new system environment variable named JAVA_HOME and set to the directory of your latest Java JDK (in my case that will be C:\Program Files\Java\jdk1.7.0_0_05) Eclipse You need to setup or obtain a J2EE version of Eclipse ( I recommend the latest package at the time of this writing is Juno. I always download the Eclipse IDE for Java EE Developers. The package is quite large (221 MB). I use a previous version (Helios) to do my software development. That package is still available online. If you want your screen to appear similar to my screenshots then I recommend you download that version. All you need to do is unzip to your hard drive and start working (C:\eclipse). Setting up for programming using Eclipse I usually create one area on my C drive where I save all my java workspace. A workspace is the location of one or more projects, usually Java Projects, that make up your workspace. For example, in one workspace I save all my practice java applets, in another all the code from the book I am currently working on, and the other contains the code for a Mario clone I got online. All the workspaces are located under the C:\ drive in a folder called JAVA_PROJECTS. This allows me to easily copy and paste

9 this directory from one machine to the next without having to give too much thought on is this the correct location for each machine. It works! Figure 12 - Workspace selection As you can see from the above figure I have several workspaces I work on. I recommend before you open eclipse (by double-clicking on C:\eclipse\eclipse application) that you first create the directory where all your Java work will be placed. C:\JAVA_PROJECTS is a good name. If this is your first time opening eclipse then click on the Browse on the button and navigate to C:\JAVA_PROJECTS and Make new folder there will be the starting point for learning Java or doing the exercises we will be providing. I recommend the name LEARN_JAVA. Figure 13 - Making new folder for these notes Enter the name of your new workspace LEARN_JAVA and click on OK button

10 Figure 14 - Prompt to enter name of new workspace Figure 15 - Click "OK" after creation

11 Figure 16 - Open the new workspace "LEARN_JAVA" Open the new workspace where you new masterpieces will be created in saved by clicking on OK Figure 17 - Eclipse "Welcome" screen When you create and open a new workspace you will first see the Welcome screen. If you like to explore you can click on any of the topics or go directly into the Workbench to get started creating projects and java code. The Workbench refers to the IDE with views and windows into your work environment.

12 Figure 18 - The workbench of your initial workspace There is not much to see yet since you just started, as we add projects and java class files you will get an idea how to use the workbench to experience best environment that has ever existed to create applications. Additional Software you may want to consider installing Apache Tomcat Since I upload applets and have the need on occasion to create and test dynamic web content (e.g. java servlets) for testing purposes. I find having Apache Tomcat installed ( quite helpful. There is not that many changes that you will need to make to it in order to use from Eclipse and there are tons of tutorials and material available on the Internet. Unzip the tomcat zip file to your hard drive (C:\apache-tomcat ). You may get something different since this is a dated version of Tomcat but all the instructions should work the same. To start tomcat open Windows Explorer and navigate to the \bin directory of your tomcat installation.

13 Figure 19 - Opening the \bin directory of Tomcat installation I usually create a folder on my desktop called Tomcat and create shortcuts to the startup.bat and shutdown.bat batch files in this folder to avoid having to navigate to this location over and over again to start up and shut down the Tomcat web server. When you click on startup Windows Batch File you will see a command prompt window open up displaying messages:

14 Figure 20 - Tomcat startup window The real test is to open a browser and enter : Figure 21 - Opening Tomcat web page

15 If you see the web page shown in the figure above then you have succeeded in getting your own personal web server running on your personal computer. To shut down the webserver just double-click on the shutdown Windows Batch program. The command window that opened up when you started should automatically close. Apache Derby Many applications including games require the ability to save and retrieve data from a database. I cool free, open source relational database is Apache Derby. It is implemented entirely in Java and it is easy to use inside and outside your java applications. The database can be downloaded from I recommend that you unzip the bin file directly onto your C:\ drive. That will install C:\db-derby bin on your machine (or something similar). Search online the Apache Derby tutorial.