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J2EEThe much awaited Java 5 has been launched in recent past by Sun. People who are in IT or related to IT industry were interested about its consequences on many factors. People who are developing applications using Java as a developing technology were more interested in new language features and other technological enhancements. But others for whom it is important to manage such process from higher level were more interested in things that are going to change with Java 5.
In this article we are going to discuss enhancements in Java 5 over prior versions that are important from management’s point of view.
Class Data Sharing
Class data sharing is new technique introduced to improve performance of JVM at run time. At run time of Java applications it loads system Jar file classes in a shared archive file, which are mapped with the memory. This helps JVM to improve its performance in two ways. One, loading classes at run time does not take much time, as they are already loaded in the archive, which is mapped with the memory. Also this architecture makes easy to share calluses among multiple JVMs.
So, from management’s point of view, Java applications will now run faster with Java 5 using class data sharing technique.
Improvements in Garbage Collection Algorithm
Improvements made in garbage collection algorithm and the process is aimed to make garbage collection more customizable and controlled by the application developer or the end user of any Java application. Both initial heap size and maximum heap size are increased to avoid memory crashes in large Java applications. Maximum heap size can be in GB now. The new parallel garbage collector allows user to set time limit and space-limit to read from heap size. The user or developers to avoid out-of-memory exception can increase these limits.
Thus, now architect and designer of the system has more control over garbage collection process in Java applications. They can configure it such a way that is scaled to achieve desired performance for the application.
Difference of Server Class Machine
Java community is already aware that the Java HotSpot JVM for server is developed and designed specially for server type machines to utilize special features of such machines and achieve best performance for the application. Here architects have got more control over usage of Java HotSpot JVM either server implementation or client.
At the startup of any Java application, it can be configured to use Java HotSpot server JVM to run the application if the underlying machine is detected to be a server machine. At run time it can detect if the machine is a server machine or simple desktop client. Based on configuration of the hardware and performance abilities, the application itself will choose suitable JVM for it.
Small Things
Other two significant enhancements in JVM with Java 5 are improved fatal error handling and new method added to System class named as nanoTime(). This method will provide access to nanosecond timings. But the result of this function will be dependent on operating system and hardware implementation like other date-time functions.
Java 2d is enhanced to take advantage of fonts installed on the operating system to render characters in multiple languages. The advantage of this improvement is, now there are ways to display characters of multiple languages at the same time provided supporting fonts are installed on the hosting operation system. JVM can detects fonts installed in various standard directories of operating system and load them as logical fonts.
Moreover AWT makes use of Unicode standards to display components on Windows XP and 2000 server. fonts cab are now rendered without limitations of Windows operating system.
Sound
Improvements in Java Sound technology are as listed here.
Improved 2D
A number of enhancements are achieved in Java 2D with launch of Java 5. Some of them are listed here.
Delivery Process
Delivery and Deployment enhancements are listed here those are introduced with Java 5.
New standard tools being offered by Sun with the release of Java 5 to help monitor, debug, maintain and tune Java applications for developers and end users are briefly discussed in this topic.
From management’s point of view, Java 5 has many things to offer including better control, improved performance, better utilization of resources, easy of development, faster development of applications, monitoring application execution etc. Also management can be interested in reporting facilities and more standard ways of developing Java applications. But being an open source technology such improvements are somewhat difficult to achieve for Java technology. But the level of flexibility it offers makes such things possible for custom tool developers using Java.
In few words, Java 5 has come with lot many improvements for management but, still we all will be looking for more in next release.