A scientist has to learn how to use tools do do
experiments. Programmers also use tools to construct and run programs.
You are suggested to first follow the instructions with a very simple
non graphical tool. In this article we explain
step by step how to
download, install and use a very popular graphical application called
Eclipse. It is free.
Wonderful! Seek help from a teacher, a coworker or a friend familiar
with programming. Show this web page to that person. Tell them you need
help executing programs written in Java version 1.5. You will quickly
be up and running.
I want to
learn how to run the programs by myself
1. Install and run Eclipse into
Important prerequisite: you
must first install the Java
Development Kit. Eclipse requires a JRE or JDK to start because
Eclipse is itself a - sophisticated - Java application with millions of
lines of Java code. JDK and Eclipse are both free.
Caveat: the following
instructions are for Windows users only. Linux and Mac users should
visit the main Eclipse
download page. Instructions will vary sensibly if your
configuration does not exactly match the one used here - Windows XP, no
Winzip. We still hope the detailed screenshots will be helpful to get
you started if you don't know anyone familiar with Java and Eclipse.
2. Wait a few minutes while the eclipse application is downloaded to
your computer. Go and enjoy a snack or a coffee and when you return you
should have the following window on your screen. Note if you use
Winzip, instructions below will not directly apply but will remain very
3. Click on 'Extract all files' in the window above. The Extraction
Wizard shown below comes up. Click 'Next'.
4. Type in c:\ to install
Eclipse under your C: drive. Click Next.
5. Wizard has completed the installation of the program Eclipse a few
moments later. Click Finish.
6. To start Eclipse, find the Eclipse folder under your C drive in the
Windows Explorer. Double click on the eclipse folder to open it.
7. Inside the eclipse folder, find the program named eclipse.exe. It
has a purple icon. Double click on eclipse.exe to start Eclipse.
8. During the startup, Eclipse asks you to specify the location of the
workspace - where we will store our Java programs. Use C:\workspace as indicated in the
screen below. It is suggested you check the option 'Use this as the
default and do not ask again'.
9. Eclipse shows up on the screen. Create a new Java Project from the
menu File, New, Java Project - as indicated below.
10. Name the new project science.
Select 'Use project folder as root for sources and class files' as
shown below. Click Finish.
11. Close the welcome page by clicking on the red button shown below.
2. Download the
programs from this website into your computer
You can repeat this step for every program you want to download. The
list of Java programs is shown at the main site.
3.Execute the Java
programs with Eclipse
1. Click on the science folder as indicated by the arrow marked with an
A below. Press the F5 key on your keyboard to refresh Eclipse. The
program PseudoRandom.java appears. You can double click on this file -
arrow marked with a B. The program is opened in an editor which you can
use to modify this program when going through the exercises - area
marked with a C.
2. Select PseudoRandom.java - arrow D - and click the white arrow in a
green circle to start the Java program PseudoRandom - arrow E.
Congratulations! You have started a Java program with the Eclipse
application. You can edit the program - area C - save it with the menu
File / Save, and start the modified program again - arrow E.