Download Installing Java (Windows) and Writing your First Program

Appendix
Installing Java (Windows) and Writing your First Program
We will be running Java from the command
line and writing Java code in Notepad++ (or
similar).
The first step is to ensure you have installed
the Java SDK. It can be downloaded from the
class webpage.
Once downloaded, install.
in order to run Java from anywhere in your
system, the files need to be added to your
PATH variable in windows.
To do this, go to ‘Control Panel’ -> ‘System’ ->
the ‘Advanced system settings’ option on the
left. Now under click ‘environment variables’
and then click edit on the PATH variable.
Once the PATH edit window appears, add a
semicolon then the path to wherever the
JAVA SDK binaries (bin) was installed. In this
example, the JDK was installed to:
C:\Program Files\Java\jdk1.6.0_24\bin
If you do not think your PATH variable is
correct you can type PATH into a command
window to display your path.
Now that you have installed Java, make a
directory for your first Java program and
open Notepad++.
Make a new file called ‘HelloWorld.java’ and
save it into the directory you made.
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Enter the following code. Java is case
sensitive, so be careful to capitalize EXACTLY
the same as what is below.
public class HelloWorld{
public static void main ( String[] args )
{
System.out.println("Hello World!\n");
}
}
To run the program, you first need to compile
the Java into byte code and then run it with
the Java virtual machine.
Open a command line and change to the
directory where your class (program) is
saved. Type the following two commands:
javac HelloWorld.java
java HelloWorld
Installing Java (Linux) and Writing your First Program
We will be running Java from the command
line and writing Java code in Gedit (or
similar).
The first step is to ensure you have installed
the Java SDK. It can be installed with the
following commands:
sudo apt-get install sun-java6-plugin
sudo apt-get install sun-java6-jdk
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Now that you have installed Java, make a
directory for your first Java program and
open Gedit.
Make a new file called ‘HelloWorld.java’ and
save it into the directory you made.
Enter the following code. Java is case
sensitive, so be careful to capitalize EXACTLY
the same as what is below.
public class HelloWorld{
public static void main ( String[] args )
{
System.out.println("Hello World!\n");
}
}
To run the program, you first need to compile
the Java into byte code and then run it with
the Java virtual machine.
Open a command line and change to the
directory where your class (program) is
saved. Type the following two commands:
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Installing Java (Mac) and Writing your First Program
Java is installed by default on Mac OS, make a
directory for your first Java program and
open your editing program.
Make a new file called ‘HelloWorld.java’ and
save it into the directory you made.
Enter the following code. Java is case
sensitive, so be careful to capitalize EXACTLY
the same as what is below.
public class HelloWorld{
public static void main ( String[] args )
{
System.out.println("Hello World!\n");
}
}
To run the program, you first need to compile
the Java into byte code and then run it with
the Java virtual machine.
Open a terminal and change to the directory
where your class (program) is saved. Type the
following two commands:
javac HelloWorld.java
java HelloWorld
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FTDI/Serial Installation
Installing the FTDI drivers and a Terminal Program in Windows
1. Most versions of windows already have the
FTDI driver as part of the operating system.
Simply connect your Wunderboard to the
‘Serial Connection’ usb port on the
Wunderboard and to your computer.
2. If your computer asks for a driver, cancel it
and download and install the ‘Virtual Com
Port (VCP)’ drivers from the website below:
http://www.ftdichip.com/Drivers/VCP.htm
3. Once installed, download and install a
Terminal program. We recommend
Termite. It can be found at:
http://www.compuphase.com/software_termite.ht
m
4. Once everything is installed, connect your
Wunderboard as described in step 1. Give
your computer time to setup drivers and
then open the Termite program.
Everything is functional if under ‘Port’ in
the Settings menu, you can select a COM
port.
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Installing the FTDI drivers and a Terminal Program in Linux
1. Most versions of Linux already have the
FTDI driver as part of the operating
system.
Simply connect your Wunderboard to the
‘Serial Connection’ usb port on the
Wunderboard and to your computer.
2. If your computer asks for a driver, cancel
it and download and install the ‘Virtual
Com Port (VCP)’ drivers from the website
below:
http://www.ftdichip.com/Drivers/VCP.htm
This is not an ideal option as you will need to
compile the files yourself.
3. Once installed, download and install a
Terminal program. We recommend
CuteCom. Open a terminal and type:
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4. Once everything is installed, connect your
Wunderboard as described in step 1. Give
your computer time to setup drivers and
then open the Cutecom program by
typing cutecom into a terminal.
Everything is functional if under ‘Device’
you can select a /ttyUSB port.
Installing the FTDI drivers and a Terminal Program on Mac
1. Connect your Wunderboard to the ‘Serial
Connection’ usb port on the
Wunderboard and to your computer.
2. To install the driver, download and install
the ‘Virtual Com Port (VCP)’ drivers from
the website below:
http://www.ftdichip.com/Drivers/VCP.htm
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3. Once installed, Open a terminal and type:
ls /dev/tty.*
This will display all possible tty devices. The
Wunderboard will be called something like
tty.usbserial
To connect to the Wunderboard, now type:
screen /dev/tty.usbserial-A800fpKA 9600
Your device maybe a different name, change
as needed.
4. To use screen, refer to the information
found here:
http://www.cheat-sheets.org/savedcopy/screen.cheat.sheet.txt
Doxygen
There are many different philosophies on how much documentation is enough and how it should be done. Many
companies have a standard method that all of their employees must follow. In this manual, one method will be shown
and expected. While other ways might seem sufficient, you must adhere to the philosophy in this manual. The
commenting style used is Doxygen.
When documenting code, essentially every line of code that is not a simple assignment should have an inline comment.
These ‘tags’ tell Doxygen that there is information inside of them to be processed. In addition to in line comments, well
documented code includes comments for: variables, functions, includes, defines, and flow control.
•
Variables
When documenting a variable use a Doxygen comment following the variable definition. The style for a
following comment is: /**< comment text */ Unless all variables are of an identical type and are used in
essentially the same way, they should be declared on separate lines with a comment for each.
•
Functions
Functions have the most complicated definition. Functions should only be defined once. The definition should
precede the function. Every function should have a brief description, all parameters defined, and the return
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value defined. For example, Documentation for the function ‘main’ might look like:
/** @brief Main Function
@param void This function does not accept any input variables
@return This function would return an error code to the OS if needed.
*/
int main (void) {
...
code
...
}
•
Includes
When documenting an include use a Doxygen comment following the include statement. The style for a
following comment is: /**< why is this file included? */
•
Defines and Variables
When documenting a define use a Doxygen comment following the #define or variable definition. All variable
and #defines should be commented if the name is not self-evident or there is another special reason for the
definition. The style for a following comment is: /**< why is this define needed? */
•
Logic Control
All statements that control flow of code must be commented. This includes; if(), while(), switch(), and for()
statements. These comments should explain why the logic test exists, not just re-iterate what is already written.
Ensure that every option has a following comment of the format: /**< comment */
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