Java Phobia: How to Install JDK 7 in different operating System

How to Install and
Get Started with Java Programming
(on Windows, Mac & Ubuntu)

Java Development Kit (JDK) 1.7 (officially named Java SE 7), which is freely available from Sun Microsystems (now part of Oracle), is needed for writing Java programs. JDK can be downloaded from the Java mother site @ http://java.sun.com (or http://www.oracle.com/technetwork/java/javase/downloads/index.html).

JDK or JRE?

JRE (Java Runtime) is needed for running Java programs. JDK (Java Development Kit), which includes JRE plus the development tools (such as compiler and debugger), is need for writing as well as running Java programs. Since you are supposed to write Java Programs, you should install JDK, which includes JRE.

JDK Versions

The various JDK versions are:

JDK Alpha and Beta (1995): Sun announced Java in September 23, 1995.
JDK 1.0 (January 23, 1996): Originally called Oak (named after the oak tree outside James Gosling's office). Renamed to Java 1 in JDK 1.0.2.
JDK 1.1 (February 19, 1997): Introduced AWT event model, inner class, JavaBean, JDBC, and RMI.
J2SE 1.2 (codename Playground) (December 8, 1998): Rebranded as "Java 2" and renamed JDK to J2SE (Java 2 Standard Edition). Also released J2EE (Java 2 Enterprise Edition) and J2ME (Java 2 Micro Edition). Included JFC (Java Foundation Classes - Swing, Accessibility API, Java 2D, Pluggable Look and Feel and Drag and Drop). Introduced Collection Framework and JIT compiler.
J2SE 1.3 (codename Kestrel) (May 8, 2000): Introduced Hotspot JVM.
J2SE 1.4 (codename Merlin) (February 6, 2002): Introduced assert, non-blocking IO (nio), logging API, image IO, Java webstart, regular expression support.
J2SE 5.0 (codename Tiger) (September 30, 2004): Officially called 5.0 instead of 1.5. Introduced generics, autoboxing/unboxing, annotation, enum, varargs, for-each loop, static import.
Java SE 6 (codename Mustang) (December 11, 2006): Renamed J2SE to Java SE (Java Standard Edition).
Java SE 7 (codename Dolphin) (July 28, 2011): First version after Oracle purchased Sun (called Orcale JDK).
Java SE 8: expected in summer 2013.Originally slated for release in September, Java 8 has been delayed until March of next year,

1. How To Install JDK on Windows

Step 1: Download JDK

Goto JavaSE download site @ http://www.oracle.com/technetwork/java/javase/downloads/index.html
Click the "Download" button under "JDK" of "Java SE 7".
Choose your operating platform, e.g., Windows x86 for 32-bit Windows OS or Windows x64 for 64-bit Windows OS. You can check whether your Windows OS is 32-bit or 64-bit via "Control Panel" ⇒ System ⇒ Under the "System Type".

Step 2: Install JDK and JRE

Run the downloaded installer (e.g., "jdk-7uxx-windows-i586.exe"), which installs both the JDK (Java Development Kit) and JRE (Java Runtime). By default, the JDK will be installed in directory "C:\Program Files\Java\jdk1.7.0_{xx}", where {xx} denotes the latest upgrade number; and JRE in "C:\Program Files\Java\jre7".

For novices, accept the defaults. Simply click "next"..."next"... to install JDK in "C:\Program Files\Java\jdk1.7.0_{xx}" and JRE in "C:\Program Files\Java\jre7". Take note of you JDK installed directory. I shall refer to the JDK installed directory as <JAVA_HOME>, hereafter, in this article.

(For Advanced Users Only) The default JDK/JRE directories work but I recommend avoiding "Program Files" directory because of thatblank character in the directory name. You may change the installed directories for JDK and JRE during installation. I personally installed JDK and all my programming tools in "d:\bin" (instead of "C:\Program Files") for ease of maintenance.

Step 3: Include JDK's "bin" Directory in the PATH

Windows OS searches the current directory and the directories listed in the PATH environment variable for executable programs. JDK's programs (such as Java compiler javac.exe and Java runtime java.exe) reside in directory "<JAVA_HOME>\bin" (where <JAVA_HOME> denotes the JDK installed directory, e.g., C:\Program Files\Java\jdk1.7.0_{xx}). You need to include the "<JAVA_HOME>\bin" directory in the PATH.

To edit the PATH environment variable in Windows 2000/XP/Vista/7/8:

Click "Start" button ⇒ "Control Panel" ⇒ "System" ⇒ (Vista/7/8 only) "Advanced system settings".
Switch to "Advanced" tab ⇒ "Environment Variables..."
In "System Variables" box, scroll down to select "PATH" ⇒ "Edit..."
(CAUTION: Read this paragraph 3 times before doing this step! There is no UNDO) In "Variable value" field, INSERT "c:\Program Files\Java\jdk1.7.0_{xx}\bin" (VERIFY that this is your JDK's binary directory) IN FRONT of all the existing directories, followed by a semi-colon (;) which separates the JDK's binary directory from the rest of the existing directories. DO NOT DELETE any existing entries; otherwise, some existing applications may not run.
```
Variable name  : PATH
Variable value : c:\Program Files\Java\jdk1.7.0_{xx}\bin;[exiting entries]
```

(For Advanced Users Only)

I suggested that you place the JDK bin directory in front of "c:\windows\system32" and "c:\windows". This is because some Windows systems may have an out-dated copy of JDK/JRE in these directories. Do a search for "java.exe", and you will be amazed by the findings.

You could read "Java Applications and Environment Variable" for more discussions about PATH environment variable.

I also recommend that you define an environment variable called JAVA_HOME, which contains the JDK installed directory, and include the JDKbin directory in the PATH via JAVA_HOME, i.e., PATH=%JAVA_HOME%\bin;.....

Step 4: Verify the JDK Installation

Launch a CMD shell (Click "Start" button ⇒ run... ⇒ enter "cmd"; or "Start" button ⇒ All Programs ⇒ Accessories ⇒ Command Prompt).

Issue a "path" command to list the contents of the PATH environment variable. Check the output and make sure that <JAVA_HOME>\bin is listed in the PATH.
```
prompt> path
PATH=c:\Program Files\Java\jdk1.7.0_{xx}\bin;[other entries]
```

Issue the following commands to verify that JDK/JRE are properly installed and display their version:

prompt> java -version
java version "1.7.0_{xx}"
Java(TM) SE Runtime Environment (build 1.7.0_{xx}-b11)
Java HotSpot(TM) Client VM (build 23.3-b01, mixed mode, sharing)
 
prompt> javac -version
javac 1.7.0_{xx}

Step 5: Write a Hello-World Java Program

Create a directory to keep all your works, e.g., d:\myproject, or any directory of your choice. Do NOT save your works in "Desktop" or "Documents" as they are hard to locate. The directory name shall not contain blank or special characters. Use meaningful but short name as it is easier to type.

Launch a programming text editor (such as TextPad or NotePad++). Begin with a new file and enter the following source code. Save the file as "Hello.java", under your work directory (e.g., d:\myproject).

/*
 * First Java program to say Hello
 */
public class Hello {   // Save as "Hello.java" under "d:\myproject"
   public static void main(String[] args) {
      System.out.println("Hello, world!");
   }
}

Step 6: Compile and Run the Hello-World Java Program

To run the program, invoke the Java Runtime "java":
```
D:\myproject> java Hello
Hello, world!
```
2. How to Install JDK on Macs

Step 1: Check if JDK has been Pre-Installed

In some Mac systems (earlier than Mac OS X 10.7 (Lion)), JDK has been pre-installed. To check if JDK has been installed, open a "Terminal" (Go ⇒ Utilities ⇒ Terminal) and issue these commands:
```
$ javac -version
```
- If a JDK version number is returned (e.g., JDK {1.x.x}), then JDK has already been installed. Proceed to "Step 3: Write a Hello-world Java program".
- If message "command not found" appears, JDK is NOT installed. Proceed to the "Step 2: Install JDK".
- If message "To open javac, you need a Java runtime" appears, select "Install" and follow the instructions to install JDK. Then, proceed to "Step 3: Write a Hello-world Java program".
Step 2: Download and Install JDK
1. Goto http://connect.apple.com.
2. Login with your AppleID.
3. Download "Java for Mac OS X {10.x} Update {u} Developer Package (DMG)". Choose {10.x} according to your Mac OS X version and the latest{u}.
4. Double-click to install the downloaded Disk Image (DMG) file.
5. Eject the DMG file.
6. To verify your installation, open a "Terminal" and issue these commands:
```
// Check the version of "javac" (Java Compiler) and "java" (Java Runtime)
$ javac -version
javac {1.x.x_xx}
 
$ java -version
java version "{1.x.x_xx}"
Java(TM) SE Runtime Environment (build {1.x.x_xx-xxx})
Java HotSpot(TM) Client VM (build 22.1-b02, mixed mode, sharing)
 
// Find the location of "javac" (Java Compiler) and "java" (Java Runtime)
$ which javac
/usr/bin/javac
 
$ which java
/usr/bin/java
```
Step 3: Write a Hello-World Java Program
1. Create a directory called "myproject" under your home directory (Finder ⇒ Go ⇒ Home; File ⇒ New Folder ⇒ "myproject").
  In Macs under the Terminal, the home directory of the current login user is denoted as "~". Hence, this new directory is represented as "~/myproject".
2. Use a programming text editor (such as jEdit, gedit) to input the following source code and save as "Hello.java" under the directory "~/myproject" created earlier.
  If you use "TextEdit" (NOT encouraged, as it is a plain text editor, NOT a programming text editor), you need to open a new file ⇒ choose "Format" ⇒ "Make Plain Text" ⇒ Enter the source code ⇒ Save as "Hello.java" (without the ".txt").
```
/*
 * My First Java program to say Hello
 */
public class Hello {   // Save as "Hello.java" under "~/myproject"
   public static void main(String[] args) {
      System.out.println("Hello, world from Mac!");
   }
}
```
Step 4: Compile and Run the Hello-World Java Program
1. To compile the source code "Hello.java", open a new "Terminal" (Go ⇒ Utilities ⇒ Terminal) and issue these commands (as illustrated):
```
// Change Directory (cd) to where "Hello.java" resides
// i.e., sub-directory "myproject" under home (~)
$ cd ~/myproject
 
// Check if "Hello.java" exists using list (ls) command
$ ls
Hello.java   ......
 
// Compile "Hello.java" using JDK compiler "javac"
$ javac Hello.java
// If error message appears, debug your source code
 
// Check for the output "Hello.class"
$ ls
Hello.class   Hello.java   ......
```
2. To run the Hello-world, invoke the Java Runtime "java" as follows:
```
// Run "Hello.class"
$ java Hello
Hello, world from Mac!
```

To compile the source code "Hello.java":

Start a CMD Shell (Click "Start" button ⇒ Select "run..." ⇒ Enter "cmd"; or "Start" button ⇒ All Programs ⇒ Accessories ⇒ Command Prompt).
Set the Current Drive to the drive where you saved your source file "Hello.java". For example, suppose that your source file is saved in drive "d", enter "d:" as follow:
```
prompt> d:
D:\xxx>
```
Set the Current Working Directory to the directory that you saved your source file via the cd (Change Directory) command. For example, suppose that your source file is saved in directory "d:\myproject".
```
D:\xxx> cd \myproject
D:\myproject>
```
Issue a dir (List Directory) command to confirm that your source file is present in the current directory.
```
D:\myproject> dir
......
08-May-XX  06:25 PM               277 Hello.java
......
```
Invoke the JDK compiler "javac" to compile the source code "Hello.java".
```
D:\myproject> javac Hello.java
```
The compilation is successful if the command prompt returns. Otherwise, error messages would be shown. Correct the errors in your source file and re-compile. Check "Common JDK Installation Errors", if you encounter problem compiling your program.

The output of the compilation is a Java class called "Hello.class". Issue a dir (List Directory) command again to check for the output.

D:\myproject> dir
......
xx-xxx-xx  01:53 PM               416 Hello.class
xx-xxx-xx  06:25 PM               277 Hello.java
......


Step 1: Download and Install JDK

Goto JDK (Java SE) download site @ http://www.oracle.com/technetwork/java/javase/downloads/index.html. Select "Java SE 7ux" ⇒ JDK ⇒ Download ⇒ "Accept Licence Agreement" ⇒ Select Linux x86 (for 32-bit system) or Linux x64 (for 64-bit system) "tar.gz" package, e.g., "jdk-7ux-linux-i586.tar.gz". (Check Settings ⇒ Details or issue command "file /sbin/init" to check your OS version.) The tarball will be stored in folder "~/Downloads", by default.
We shall install JDK under "/usr/local/java". First, create a directory "java" under "/usr/local". Open a Terminal and issue these commands:$ cd /usr/local
$ sudo mkdir java
Extract the downloaded package (Check your downloaded filename!)$ cd /usr/local/java
$ sudo tar xzvf ~/Downloads/jdk-7u{xx}-linux-x64.tar.gz
JDK shall be extracted in a folder "/usr/local/java/jdk1.7.0_{xx}", where {xx} is the upgrade number.
Add JDK's binary directory ("bin") to the PATH by editing "/etc/profile":$ cd /etc
$ gksudo gedit profile   // OR "sudo nano profile" to use the console-based nano editor
Add these lines at the end of the file "/etc/profile", replace "{xx}" with the actual number:export JAVA_HOME=/usr/local/java/jdk1.7.0_{xx}
export PATH=$PATH:$JAVA_HOME/bin
Rerun the configuaration file by:$ source /etc/profile
 
// Check the new settings for JAVA_HOME and PATH
$ echo $JAVA_HOME
/usr/local/java/jdk1.7.0_{xx}
 
$ echo $PATH
.....:/usr/local/java/jdk1.7.0_{xx}/bin

To use Java under Firefox, you need to enable the so-called "Java Plugin for web browser".$ cd /usr/lib/mozilla/plugins
// if this directory does not exist, create it
$ sudo mkdir -p /usr/lib/mozilla/plugins
Then, create a symbolic link to your Mozilla plugins folder, (check your JDK folder)$ cd /usr/lib/mozilla/plugins
$ sudo ln -s /usr/local/java/jdk1.7.0_{xx}/jre/lib/amd64/libnpjp2.so
To verify the installation, restart your Firefox and issue URL "about:plugins" to view the status of the plugins (check for java plugins with the correct version).
To verify the JDK installation, issue these commands:// Show the Java Compiler (javac) version
$ javac -version
JDK 1.7.0_07
 
// Show the Java Runtime (java) version
$ java -version
......
 
// Show the location of javac and java
$ which javac
/usr/local/java/jdk1.7.0_{xx}/bin/javac
$ which java
/usr/local/java/jdk1.7.0_{xx}/bin/java

Inform the Ubuntu about the Oracle JDK/JRE:// Setup the location of java, javac and javaws
$ sudo update-alternatives --install "/usr/bin/java" "java" "/usr/local/java/jdk1.7.0_17/jre/bin/java" 1
      // --install link name path priority
$ sudo update-alternatives --install "/usr/bin/javac" "javac" "/usr/local/java/jdk1.7.0_17/bin/javac" 1
$ sudo update-alternatives --install "/usr/bin/javaws" "javaws" "/usr/local/java/jdk1.7.0_17/jre/bin/javaws" 1
 
// Use this Oracle JDK/JRE as the default
$ sudo update-alternatives --set java /usr/local/java/jdk1.7.0_17/jre/bin/java
$ sudo update-alternatives --set javac /usr/local/java/jdk1.7.0_17/bin/javac
$ sudo update-alternatives --set javaws /usr/local/java/jdk1.7.0_17/jre/bin/javaws



Step 2: Compile and Run a Hello-world Java Program

Open "Folder" and create a new directory called "myproject" under your home directory to keep all your works.
Open "Text Editor" (gedit). Enter the following source code and save as "Hello.java" under the "~/myproject" directory created eariler.public class Hello {   // To save as "Hello.java" under "~/myproject"
   public static void main(String[] args) {
      System.out.println("Hello, world from Ubuntu!");
   }
}

To compile the Hello-world Java program, launch a Terminal and issue these commands:// Change directory to where the source code resides
$ cd ~/myproject
 
// List the contents of current directory. Check for "Hello.java"
$ ls
...... Hello.java ....
 
// Compile "Hello.java" into "Hello.class"
$ javac Hello.java
 
// Check for "Hello.class"
$ ls
...... Hello.class ....

Run the Hello-world Java program:// Run "Hello.class"
$ java Hello
Hello, world from Ubuntu!

Updates

Tuesday 30 July 2013

How to Install JDK 7 in different operating System

How to Install and
Get Started with Java Programming
(on Windows, Mac & Ubuntu)

JDK or JRE?

JDK Versions

1. How To Install JDK on Windows

Step 1: Download JDK

Step 2: Install JDK and JRE

Step 3: Include JDK's "bin" Directory in the PATH

Step 4: Verify the JDK Installation

Step 5: Write a Hello-World Java Program

Step 6: Compile and Run the Hello-World Java Program

2. How to Install JDK on Macs

Step 1: Check if JDK has been Pre-Installed

Step 2: Download and Install JDK

Step 3: Write a Hello-World Java Program

Step 4: Compile and Run the Hello-World Java Program

Step 1: Download and Install JDK

Step 2: Compile and Run a Hello-world Java Program

No comments:

Post a Comment

Updates

Tuesday 30 July 2013

How to Install JDK 7 in different operating System

How to Install andGet Started with Java Programming (on Windows, Mac & Ubuntu)

JDK or JRE?

JDK Versions

1. How To Install JDK on Windows

Step 1: Download JDK

Step 2: Install JDK and JRE

Step 3: Include JDK's "bin" Directory in the PATH

Step 4: Verify the JDK Installation

Step 5: Write a Hello-World Java Program

Step 6: Compile and Run the Hello-World Java Program

2. How to Install JDK on Macs

Step 1: Check if JDK has been Pre-Installed

Step 2: Download and Install JDK

Step 3: Write a Hello-World Java Program

Step 4: Compile and Run the Hello-World Java Program

Step 1: Download and Install JDK

Step 2: Compile and Run a Hello-world Java Program

No comments:

Post a Comment

How to Install and
Get Started with Java Programming
(on Windows, Mac & Ubuntu)