Tutorial On The
Windows Operating System & Eclipse IDE

Every quarter about 250 CS students successfully complete this process. Please feel free to ask other students if you get stuck; and, if someone gets stuck and asks you a question, please try to help them. Mastering the use of the operating system is NOT an academic part of the course, so feel free to give and take help.

When you arrive at a machine, you should see a Welcome to Windows window displayed; if not, wiggle the mouse until you see this window. Then

• Hold down the Ctrl and Alt keys and press the Del key (often written Ctrl+Alt+Delete); a helpdesk@ics.uci.edu window will pop up, welcoming you to the School of ICS Computer labs.
• Click the OK button; a Log On To WIndows window will pop up, asking you to supply your name and password.
• Ensure the last box, labelled Log on to: shows UCI-ICS and NOT the name of your computer (use the pull-down menu if you must change this selection).
• Click the button labelled OK or press the Enter/Return key.

• Drag and Drop all your folders/files from the desktop into the Recycle Bin icon.
• Drag and Drop all your folders/files from c:\Documents and Settings\yourname\eclipse\workspace into the Recycle Bin icon.
• Double Click the Recycle Bin icon.
• Select File | Empty Recycle Bin.
• Click Yes for Confirm multiple File Delete.

• ClickStart and select logout.

and then click the Log Off button. In fact, to ensure that this operation is successful, you should wait until the Welcome to Windows window is redisplayed.

• Open an Explorer window: click the My Computer icon, if it is on the desktop,
  or click Start and then select My Computer.
• Select View | Choose Details...
• Put a check in the Type box (probably third from top).
• Click OK

• Right Click the folder or file.
• In its context menu, click the Rename option.
• Type the new name (and the same extension) in the highlighted blue box.

To zip all the files in a folder named F, into a single zip file (typically occuping less space)

• Right Click the folder named F.
• In its context menu, first hover over the Send To option, then select the Compressed (zipped) Folder option.

When this operation finishes you should see a new file on your desktop (or wherever the folder you zipped came from) with the same names as your folder (the folder will still be there too) and the zip file extension. So, in this case, the zip file is named F.zip). Its icon will show a zipper across the folder (other software chose a C-clamp compressing the folder.

• Double Click the zip file that you want to unzip. You will see window like the picture below.

  

• Drag the folder F from the F.zip onto the desktop (or into any folder).
• Terminate (X) the F.zip window.

It is important to be able to

• Double Click any browser icon on your destkop (e.g, Internet Explorer)
• Enter the url http://www.ics.uci.edu/~pattis/ and press the Enter key.
• From my homepage, select your web for your course; if you have your own machine, place a bookmark to this page in your browser so that you can reach it quickly and easily.

Here is a brief description of these main entries

• Fact Sheet: A short page providing information about course staff, getting help, and meeting times; this is the default page for the course.
• Announcements: A page with messages to the students (updated almost daily, archived with the most current message at the top).
• Email Archive: A page with links to all messages mailed to the email discussion group for this class.
• Syllabus: A long page providing detailed information about how the course is run (print a copy and read it).

• Lecture Schedule/Notes: A page indexing all lectures, and their on-line lecture notes and their associated problem sets (and labs too).
• Programming Assignments: A page indexing all programming assignments.
• Weekly Schedule: A page listing all readings and homework assignments (and their due dates), week by week.
• Help Schedule: A page listing all the times help is available to students, both inside and outside of class.

• Handouts (General): A page indexing a variety of handouts related to the course.
• Online Resources: A page indexing various useful on-line files (some meant to be viewed, some meant to be downloaded).
• Sample Programs: A page indexing various programs students can download, examine, and run.

• Javadoc of Sun's API: Documentation of Sun's standard Java classes.
• Javadoc of Courses API: Documentation of the introlib standard Java classes.
• Java Language Reference: Documentation of the Java Language; see the (table of) contents for details

• Solutions: A page indexing my solutions to all course assignments (quizzes, exams, and programs); updated as appropriate
• Grades: A zipped file you can download with all course grades (indexed by the last 5 digits of your UCI ID).

• Anonymous Email: A page students use to send the instructor anonymous email (when personal email might be awkward).
• Homework Dropoff: A page students use to drop off homework (mostly weekly programming assignments and in-class programming exams). Our homework dropoff system is called Checkmate

• Search ICS-21: Do a "google" search of the course web pages.
• Search Javadoc 1.6 API: Do a "google" search of the Java API.

If you want to find some keyword on a web page, type Ctrl F or select Edit | Find on this page (Windows IE) or Edit | Find in This Page... (Firefox), then enter the keyword, and click the Next button/icon. This searching mechanism can be a great help if you know some information is on a long web document, but don't know where in the document it appears.

During this course you will be constantly reading web pages, and sometimes downloading materials from them onto your computer. Generally, it is critical to become an expert navigating the course web with a browser; specifically you should become familiar with the pages used repeated in this course (so that you can easily find all the materials you need).

If you run across any "missing links", please drop me a short e-mail so that I can correct them quickly.

• If you Right Click a download link, select Save target as ... (from Microsoft IE) or Save Link As ... (from Firefox) from the context menu.
• If you Left Click a download link, you will see a pop-up box that allows you to open the file or save it to the (hard) disk of your computer; select saving. In fact, it may even popup an Unknown file type window, in which case you should again select the saving option.

The easiest place to save the file is on the Desktop. If Desktop is not in the Save In: box, click the yellow folder icon to its right (the one with the up-pointing arrow) repeatedly until Desktop appears. Then click Save. If you did not want to download that file, click Cancel at any time.

When you click on a download link, Windows might automatically download the application to a special location from where you will have to retrieve it. Also, sometimes Windows will ask you whether you want to install/open up the application immediately: if prompted, you probably do NOT want to open the application. I cannot predict which of these windows will popup on your machine, but once you learn the sequence, browser downloading will be simple and natural.

Eclipse is an open source community whose projects are focused on building an open development platform comprised of extensible frameworks, tools and runtimes for building, deploying and managing software across the lifecycle. A large and vibrant ecosystem of major technology vendors, innovative start-ups, universities, research institutions and individuals extend, complement and support the Eclipse platform.

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At this point, Eclipse displays the Workspace Launcher window. If this is the first time that we have started Eclipse, this window will display a suggestion typed in the Workspace pull-down box, as shown below. If we examine this pull-down box, there will be no other items in it.

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The form of the suggested workspace is C:\Documents and Settings\username\workspace, where username appears above as Administrator.

On subsequent statups, the contents of the pull-down box will default to the last workspace that we used. It is possible to create/use multiple workspaces: the most recently used ones will appear as items in the Workspace pull-down box, with the visible workspace the one that we used most recently. This information is stored in the eclipse folder (created when Eclipse was installed), in the file configuration\settings\org.eclipse.ui.ide.prefs (which is a text file that you can read and even edit.

If we use just one workspace (recommended), we can put a check in the checkbox Use this as the default and do not ask again, to avoid this window's prompt altogether. Or, we can leave this box unchecked, at the cost of having to click the OK button in this window every time that we start Eclipse.

Go ahead now and click the OK button to select the default work space (or Browse... or type in a folder name). The splash screen will disappear and Eclipse should appear on the screen in the following form (although its windows will be bigger).

• Download (right-click and Save Target As) Course Library Jar into the same folder that you are using as your workspace (or move this file in the workspace folder after downloading it elsewhere).

• In Eclipse, select Window | Preferences

• Click the + in front of Java or double-click Java (after the +)

• Click Installed JREs

  You should see the following screen

Workbench/Workspace: These two terms are closely connected, to the point of having the same prefix. A workbench (or more accurately, a workbench window -see the window below) is the Eclipse interface to a workspace. A workspace is a folder that comprises a collection of files/subfolders that store the workspace's preferences (how the workbench window appears on the screen and how it displays/manipulates it contents) and projects (collections of related programming resources -primarily Java classes). We interact with a workspace -view and manipulate its preferences and projects- through a workbench window.

Preferences specify how a workbench window displays a workspace; projects specify the software that we can develop using the workbench window. In the section above, we started Eclipse and created a new, "empty" workspace; actually, it is not really empty: it stores all the standard initial preferences for the workbench window, but no projects. Then, the workbench window displayed this "empty" workspace.

So, a workspace stores information about each of its projects in a separate folder. It knows where all their resources are located, whether they are inside or outside the workspace. Yes, a project folder (always stored inside a workspace) can store some or all of its resources outside that workspace. The workspace also records whether each project it contains is open or closed for use (for more details, see the section on Closing Workspaces). Finally a workspace stores preferences that apply to all its projects, and to the workbench using the workspace.

Eclipse is general: we can have any number of workbench windows open, each referring to a unique workspace, or groups of windows referring to a common workspace. For simplicity, we will always use just one workbench window, and it will always refer to the same workspace. In fact, in the following discussion we often will say "Eclipse" when we mean "workbench window": e.g. We use Eclipse to interact with a workspace. Below is an example of Eclipse using all the standard preferences, with labels affixed to many of it interesting features. The rest of the this section will explain its layout and operation.

Before starting any project, we should set the preferences for Eclipse to show (and default to) the Java perspective. Generally, we can manipulate perspectives in a few interesting ways.

• We can remove a perspective from our view by right-clicking its tab and selecting Close.
• We can bring back a closed perspective P by selecting Window | Open Perspective | P or by clicking the Open Perspective button and selecting P.
• We can drag the left edge of the tab holding the perspective left/right to lengthen/shorten it.
• We can elide the perspective names, just displaying their icons, by right-clicking any perspective and selecting Show Text (toggling whether it is shown).
• We can rearrange the order of the perspective tabs by dragging each to its desired location.
• We can dock these tabs at the Top Right, Top Left, and Left of the Ecplipse window by right clicking any perpsective tab and selecting Dock On, and then the appropriate location.

• Click the Open perspective button appearing before it on the tab and select the Debug perspective.
• Move the Java perspective to be on the left of the Debug perspective.
• Click the Java perspective.

To start a new project, click the New Java Project button on the tool bar for the Java perspective. The following New Project Window will appear.
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In this window I have created a project whose name is Demo; this project is stored in a folder named Demo. Eclipse enforces this name convention. For a simple project, just click Finish when you are done typing the project name; clicking Next leads to another window of options, which we would default anyway and are ultimately accepted just by clicking Finish here.

To create a new class inside this project, click the New Java Class button on the tool bar for the Java perspective. The following New Class Window will appear.
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In this window I have created a class whose name is Application, inside the anonymous package, inside the project named Demo. While Eclipse does not recommend using the anonymous package for advanced programmers, as beginners we will use the anonymous package for a while.

Because I put a check in the appropriate checkbox, Eclipse will automatically include a main method for the Application class. Click Finish when you are done typing the name and checking the box.

Eclipse will update to look like the following.

Whenever we create a new class, or double click any class in an Package Explorer, Eclipse will add a view/tab for editing that class in the editor window (if such a view is not already present). To add a second editor view/tab for a class -so that we can view two parts of it simultaneously- we can right-click its view/tab and select New Editor. Within an editor window, we can manipulate views/tabs as described above, including dividing one editor window into two editor windows, vertically or horizontally.

Note that in this editor, a single click positions the cursor; a double click selects a token; dragging the cursor selects multiple characters/tokens (depending on whether the dragging started after a single or double click).

After creating a new class, the editor window looks like as follows. Practice selecting text (characters, tokens, lines) in this window.

The first time you run a Java program, you will see the following window

As shown, put a check in the Always save resources before launching checkbox and the click OK. In this way, whenever you run the program, Eclipse will automatically save all the files you changed before starting to run your program.

When you run a class in the Java perspective, a Console view automatically appears and becomes active on the bottomost window (along with the Problems, Javadoc, and Declaration views). When run this way, the code listed in the last section, displays the following windows.

First, notice that information entered by the user appears in a green font; information displayed by the computer appears in a black font. Also notice that the line below the Console tab shows that the main method has run to completion -it is terminated. The interaction appears in the contents of the Console, view: if it does note fit entirely in this view, its contents can be scrolled -both vertically and horizontally.

There are two useful tool buttons to the right of this tab. Immediately to the right is the Terminate button, a faded-red square that stops a running program (it is faded here, because it cannot be selected: the program already is terminated). The third one is the Clear Console button, which clears the contents of the console (Eclipse does this automatically, when it runs a program).

The Console window below shows this program in the middle of running; it is waiting for the user to enter the limit.

Here the line below the Console tab does NOT indicate that the main method has terminated. So, the Terminate button is bright red; pressing it will stop the program.

Once we have successfully run a program, we can use the Run button on the workbench tool bar () to rerun the program very easily. How do we know whether or not we can use this shortcut? If we hover over this button, below it will display either Run by itself or Run X where X is the name of the class whose main method will run if we click this button. Typically, it shows the name of the class that was last run successfully and it will rerun the program in that class again. If it will not run that class, first right-click the editor view for that class, and then select Run As and Java Application.

Practice all these operations until you are comfortable using the Console view while running and rerunning programs.

The universal color for a syntax error indicator in Eclipse is red; the universal indicator for a syntax error in Eclipse is a red backgound (often a box, sometimes a circle) containing an X (e.g., ). Often a single syntax error results in multiple red boxes appearing in multiple views. Likewise, the universal color for a warning indicator in Eclipse is yellow. You must stop and fix an error, but you just need to be cautious with a warning (as with driving signs). We will discuss when to pay close attention to warnings later in the quarter.

Note that if you click the Project pull-down menu, the item Build Automatically should be checked: if it isn't, click it, and the next time you click this pull-down menu it should be checked (clicking toggles it).

Eclipse tries hard to spot syntax errors while you are typing/editing your code, and help you fix them immediately. For example, after we have included the import statement in the first line, and entered the first line in the main method, the editor view reports a syntax error because we misspelled forInt as forInp. Notice that there are 4 error indicators in this editor view. The error indicator in the left margin signals that not only has Eclipse detected a syntax error, but it has a suggested fix for this error.

If we hover over any of the 3 error indicators on the line, Eclipse will display a syntax error message for that line; below, we illustate hoving over the error indicator in the left margin.

In fact, if we click on this error indicator, Eclipse suggests possible fixes.

If we then double-click on the first suggestion, Eclipse will correctly fix this error and all 4 error indicators will disappear, but they will each be replaced by an equivalent warning indicator. This is because Eclipse is configured to warn whenever we define a local variable (in this case limit) whose value is not used subsequently in the method. If you hover over the warning, Eclipse will show its contents. There is no real error here; we just haven't written that code yet that uses limit, so in this case we can ignore the warning; it will disappear once we write code that use limit.

Now assume that we type the next two lines and make a mistake on each: on the first line we write i+ instead of i++; on the second we write I instead of i. Then Java will show an error token error on the first bad line (but has no suggestions to fix it) and an slightly different looking error token on the second (for which it has suggestions to fix it); Eclipse marks both lines on the right as being in error, and underlines the problem token on each line.

When we fix this first error, then the editor view shows

If we save the file now, Eclipses not only saves the file, but it also recompiles it. After compiling this class (and still finding one error) all the views are updated to contain error indicators.

We can visit and correct each syntax error in the editor view by clicking on its line in the Problems view (generally all the syntax errors appear on these lines). We can also resize each of the columns in the Problems view. In addition, we can click on any red boxes in the right margin of the editor view; sometimes clicking the disclosure circles to the left of the code will make this operation easier.

If we correct the final error in the editor window, only the editor view changes: its error indicator in the left margin turns from red to gray. All the other error indicators in that view -and in the other views- stay the same.

Finally, we can perform two interesting operations here.

• If we save the program, Eclipse will recompile it and all the error indicators will disappear. We can then run the program.
• If we run the program immediately (before saving it), Eclipse will recompile this file (and all the error indicators disappear) and run the program. If you didn't put a check the special checkbox described at the start of this section) Eclipse will first prompt you about whether to save the file (and you will have another chance to put a check the special checkbox).

Therefore, there are at least two ways to recompile a class.

• Save the file storing the class by the right-click Save command in an editor view of that class.
• Run (or just attempt to run) a main method in some class (see the previous section for details).

The interactions among saving, compiling, and running can sometimes be a bit subtle and confusing. Confusion especially arises concerning the synchonization of the files you are editing and Eclipse's reporting of syntax errors in various views. For example, if we fix an error, its associated error indicatators may disappear from some -but not all views; we must sometimes perform further operations, like saving or recompiling to synchronize all these views. At times, recompiling by saving hasn't done what I've expected, and I've had to recompile by trying to run. There is no substitute for using Eclipse repeated to better understand its operation.

• When the Eclipse detects a problem at a token, often either that token is wrong, or the one before it is wrong (less frequently the incorrect token appears even earlier in the program, and even less frequently later). Check both places.
• Sometimes an error/warning message makes no sense: it says that there is one kind of problem in our code, but we actually have to correct a different kind of problem.
• Problems snowball: one mistake can cause many error/warning messages to appear; by fixing one mistake, many message may disappear.

• Fix the first problem (or if you are confident, the first few) Problems view. If the first error makes no sense, a subsequent error might be causing the problem (snowballing). Always find and fix at least one error; don't spend time fixing more than a few (because recompiling is so quick).
• Recomple the program.
• Repeat this process until there are no syntax errors left.
• To make progress, you must correct at least one error during each (re)compilation. And, fixing only one error at a time ensures that you won't get confused by snowball errors.

Now let us explore three options for finishing a project. We need to find out what happens to such projects both on our workbench and in our workspace. The simplest option is to just leave a project alone. It will continue to be present on our workbench and in our workspace. This is a safe option, although our workbench can be come cluttered, and we might accidentally change a project that we meant to leave alone. So, we will explore two other options: closing and deleting.

Closing: First, we can just close the project. Closed projects still appear in the Package Explorer (and Navigator) view in our workbench (and are still stored in our workspace folder), but with no disclosure square: we cannot examine, run, or modify our code in such projects. We close a project by right-clicking its name and then selecting Close Project. One of the few operations that we can perform on a closed project is to reopen it: by right-clicking its name and then selecting Open Project. Once this is done, we can explore the contents of the project again. So, if we are done with a project, we can close it (to avoid accidentally change it) but reopen it if we need to examine/change it.

Another operation is removing it from the workbench, which is discussed next.

Deleting: Our second option is actually removing a project from our workbench. In this case, the project disappears altogether from our workbench, as if it were never there. We delete a project by right-clicking its name and then selecting Delete; at this point, Eclipse displays the following confirmation window.

If we leave the Delete project contents on disk (cannot be undone) checkbox unchecked, Eclipse removes the project from its workbench, but the folders and files containing all its resources remain intact, whether inside or outside the workspace. We can leave this information where it is, or copy/move it elsewhere; at a later time, if we want to recreate the project, it will be easy to do if we still still have all this information.

But, if we put a check in the Delete project contents on disk (cannot be undone) checkbox, then Eclipse not only remove the project from its workbench, but also deletes the folders and files containing all its resources, whether inside or outside the workspace.

Obviously this latter choice is very dangerous, and I recommend NEVER putting a check in this checkbox, which always defaults to being unchecked. If need be, and after we are done done with this operation, we can delete the project folder (whether inside or outside the workspace, or archive it by moving it to any other directory on our computer.

Finally, if you see the following pop-up window,

first, check the box Always delete associated launch configurations (so you won't see this pop-up window in the future), and then click OK.

For example, we might download from the web a folder that contains a collection of files that already define various classes in a program. My Sample Programs link leads to a repository of such folders; later in the semester I will ask you to download programming project folders that contain some starter code that I have written.

The easiest way to create a new project from a project folder is first to copy (or move) that folder into the workspace directory. In fact, as we just learned, if we delete a project from a workspace, but do not delete its contents, the project folder remains in the workspace. By deleting the Demo project above, and not deleting its contents, I now have an empty workbench, but the Demo project folder is still in my workspace.

To start a new project with the resources already in the workspace (as is the case with Demo), click the New Java Project button on the tool bar for the Java perspective. The following New Project Window will appear.
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By typing Demo, the name of a project folder already in the workspace, and clicking Finish, Eclipse creates a new project from it, with all of the resources that it contains.

We don't even have to copy the project into the workspace; sometimes it is easier to use folders in other locations (like on the desktop). To start a new project with existing resources NOT in the workspace, click the New Java Project button on the tool bar for the Java perspective. The following New Project Window will appear.
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This time, I have created a project whose name is Demo2; the contents of this project is already stored in the bouncingballs folder on my desktop (you should download and unzip this file on your desktop first: right-click and Save Target As... on bouncingballs).

So long as a project referring to this folder exists is in my workbench, the bouncingballs folder should remain in this location, because although this information is not stored in the workspace, the workbench refers to it. Most importantly, all changes made to files in this project will actually be made in the folder containing its resources. If we delete the project from the workbench, and do not delete its contents, the bouncingballs folder will remain intact.

To run this program, disclose the Demo2 and (default package) in the leftmost, Package Explorer window. Then right-click on Application.Java and select Run As and then Java Application. Click in various locations on the white screen (to place balls) and then click on the Start button.

Here are some useful preference to know about.

• Disclose General and then select Startup and shutdown: determines whether or not the user is prompted when Eclipse starts (for the workspace) and stops (for confirmation).

• Disclose Java | Compiler and then select Error/Warnings: allows us to specify whether to ignore certain anomolies or mark them as errors or warnings. For example, disclose Unnecessary Code and see that Local variable is never read is set to Warning (I want to know about this inconsistency).

• Disclose Java | Editors and then select Content Assist: allows us to check/uncheck Enable auto activation. I prefer disabling this feature, and manually pressing ctrl/space when I want it.

If you are using your own computer, your files will remain there. But, it is useful to save material even from your own computer, just in case you accidentally delete it. It is a sad fact of life, but almost everyone will accidentally delete some important file during the quarter.

The simplest way to save your work is to copy it onto a USB memory stick. Such memory sticks cost about $5/gigabyte: one gigabyte will easily store all the programs that you will work on this quarter (and probably easily store all the programs you work on all year). If you do not already have (and know how to use) such a memory stick, please purchase one -they are available at the bookstore- and learn how to use it.

When you are on a lab machine, you can also copy your project folders and files onto unix backup space hosted by ICS. All students with ICS Lab accounts get this space. You can easily move folders and files from any lab PC to this space, and likewise move information from this space to a lab PC.

Start by double-clicking the My Computer icon (or left-clicking Start at the left of the task bar and then left-clicking the My Computer icon). You will see a listing for a Network Drive that will appear something like username on 'data'(H:). If you double-click on that icon/text, you will see a window that represents your unix back space. Treat it like any disk drive: you can move folders/files between your PC and this space by the same means you move folders/files on your PC alone.

Based on my evolving understanding of how to use the ICS labs, I would recommend that when you use these machines, you backup your entire workspace folder, which for the ICS lab machines is stored at c:\temp\Documents and Settings\yourname\eclipse\workspace. It would be best to zip this workspace and then copy it either/both to your Unix space and your USB memory stick (or other portable/external storage).

Once you have an activated UCInetID, you need to Login to Checkmate and enroll yourself in my ICS-21 course (you do this only once, at the start of the quarter). You will first see the UCInetID verification page