Installation of J2SDK

Installation Instructions for J2SDK
Run the self-installing executable to unpack and install the Java 2 SDK software bundle. As part of the Java 2 SDK, this installation includes the Java Plug-in and Java Web Start, as well as an option to include the public Java 2 Runtime Environment.

System Requirements
Software - Java 2 SDK Standard Edition, 1.4.2 is supported on i586 Intel and 100% compatible platforms running Microsoft Windows. For a list of supported operating systems and desktop managers, see System Configurations.

Hardware - Intel and 100% compatible processors are supported. A Pentium 166MHz or faster processor with at least 32 megabytes of physical RAM is required to run graphically based applications. At least 48 megabytes of RAM is recommended for applets running within a browser using the Java Plug-in. Running with less memory may cause disk swapping which has a severe effect on performance. Very large programs may require more RAM for adequate performance.

Installed Directory Tree
The Java 2 SDK has the directory structure shown below.

j2sdk1.4.2_
  ____________________|___________________
 |    |    |    |    |   |     |      |   |
 |    |    |    |   bin lib    |    demo  |
 |    |    | LICENSE |   |     |         jre
 |    | COPYRIGHT              |        __|__
 |  README.txt              include    |     |
readme.html                           bin   lib

In addition, the Java Plug-in and Java Web Start will automatically be installed

Setting the PATH variable

set the PATH variable if you want to be able to conveniently run the Java 2 SDK executables (javac.exe, java.exe, javadoc.exe, etc.) from any directory without having to type the full path of the command. If you don't set the PATH variable, you need to specify the full path to the executable every time you run it, such as:

    C:> \j2sdk1.4.2_\bin\javac MyClass.java 

It's useful to set the PATH permanently so it will persist after rebooting.

Microsoft Windows NT, 2000, and XP - To set the PATH permanently:

1. Choose Start, Settings, Control Panel, and double-click System. On Microsoft Windows NT, select the Environment tab; on Microsoft Windows 2000 select the Advanced tab and then Environment Variables. Look for "Path" in the User Variables and System Variables. If you're not sure where to add the path, add it to the right end of the "Path" in the User Variables. A typical value for PATH is:

        C:\j2sdk1.4.2_\bin
   

   Capitalization doesn't matter. Click "Set", "OK" or "Apply".

   The PATH can be a series of directories separated by semi-colons (;). Microsoft Windows looks for programs in the PATH directories in order, from left to right. You should only have one bin directory for a Java SDK in the path at a time (those following the first are ignored), so if one is already present, you can update it to j2sdk1.4.2_\bin.

2. The new path takes effect in each new Command Prompt window you open after setting the PATH variable.

Microsoft Windows 98 - To set the PATH permanently, open the AUTOEXEC.BAT file and add or change the PATH statement as follows:

a.) Start the system editor. Choose "Start", "Run" and enter sysedit, then click OK. The system editor starts up with several windows showing. Go to the window that is displaying AUTOEXEC.BAT

b.) Look for the PATH statement. (If you don't have one, add one.) If you're not sure where to add the path, add it to the right end of the PATH. For example, in the following PATH statement, we have added the bin directory at the right end:

PATH C:\WINDOWS;C:\WINDOWS\COMMAND;C:\J2SDK1.4.2_\BIN

1. Capitalization doesn't matter. The PATH can be a series of directories separated by semi-colons (;). Microsoft Windows searches for programs in the PATH directories in order, from left to right. You should only have one bin directory for a Java SDK in the path at a time (those following the first are ignored), so if one is already present, you can update it to j2sdk1.4.2_.

2. To make the path take effect in the current Command Prompt window, execute the following:

  C:> c:\autoexec.bat 

To find out the current value of your PATH, to see if it took effect, at the command prompt, type:

      C:> path 

Microsoft Windows ME - To set the PATH permanently:
From the start menu, choose programs, accessories, system tools, and system information. This brings up a window titled "Microsoft Help and Support". From here, choose the tools menu, then select the system configuration utility. Click the environment tab, select PATH and press the edit button. Now add the SDK to your path as described in step b above. After you've added the location of the SDK to your PATH, save the changes and reboot your machine when prompted.

Configure Environment Variables.

Open Properties of My Computer, Select [Advanced] tab, and click [Environment Variables] button. Add JAVA_HOME variable by the installed directory. (i.e. C:\j2sdk1.4.2_05). JAVA_HOME variable is necessary for Tomcat and other tools.

Edit Path enfironment and add [%JAVA_HOME%\bin;] in the existing value.

Start using the Java 2 SDK!

Creating source files in Notepad - In Microsoft Windows, when you create a new file in Microsoft Notepad and then save it for the first time, Notepad normally adds the .txt extension to the filename. Therefore, a file you name Test.java is saved as Test.java.txt. It's important to note that you cannot see the .txt extension unless you turn on the viewing of file extensions (in Microsoft Windows Explorer, uncheck "Hide file extensions for known file types" under Folder Options). To prevent the .txt extension, enclose the filename in quotation marks, such as "Test.java", when typing it into the Save As dialog box.