Java

Saturday, 27 November 2010

I started my working life as a computer programmer using PLM80 on the RMX80 real-time operating system.

I have used many languages between then and now and as this page is about Java I’ll just talk about Java – coffee cup at my side......

History and reasons to come here later.

My use of Java started when I wanted to add to my earlier web pages and noticed that add-ons were available for Java. Java is similar to Pascal and Algol and indeed PLM80. When Java is used for a web page add-on it is called an Applet. It can be used to create games and other applications that run on mobile phones. Maybe your phone runs Java games and utilities... My mobile phone collection includes a Sony Ericsson W910i and a Nokia 6330. They present the small applications that I have created in slightly different ways.

Applets

MIDlets

MIDlets may be written that run on mobile phones. Java programs run on a JVM Java Virtual Machine. The JVM runs ..... The Java program is allowed to read from the keyboard / keypad of the host device and write to the display screen but it is not allowed to access external devices unless given specific permission. These permissions include the device file store and the internet. Java has the ability to access these and many other external devices but is only allowed if the host device gives permission. (Same for all Java)

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