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Java Topic / Java tutorial The final keyword helps in making a variable unmodifiable after the initialization. If a variable is defined with final keyword, then it can not be modified after the initialization. This kind of check prevents the developers from accidentally modifying a variable, a method or a class.

What is serialVersionUID? What is it Used For???

There is given many features of java. They are also called java buzzwords. 1.Simple 2.Object-oriented 3.Platform independent 4.Secured 5.Robust 6.Architecture neutral 7.Portable 8.Dynamic 9.Interpreted 10.High Performance 11.Multithreaded 12.Distributed Simple Java is simple in the sense that: syntax is based on C++ (so easier for programmers to learn it after C++).

There is given many features of java. They are also called java buzzwords. 1.Simple 2.Object-oriented 3.Platform independent 4.Secured 5.Robust 6.Architecture neutral 7.Portable 8.Dynamic 9.Interpreted 10.High Performance 11.Multithreaded 12.Distributed Simple Java is simple in the sense that: syntax is based on C++ (so easier for programmers to learn it after C++).

"Executing external processes from Java is a well-known problem area. It is inheriently platform dependent and requires the developer to know and test for platform specific behaviors, for example using cmd.exe on Windows or limited buffer sizes causing deadlocks. The JRE support for this is very limited, albeit better with the new Java SE 1.5 ProcessBuilder class. Reliably executing external processes can also require knowledge of the environment variables before or after the command is executed. In J2SE 1.1-1.4 there is not support for this, since the method, System.getenv(), for retriving environment variables is deprecated. There are currently several different libraries that for their own purposes have implemented frameworks around Runtime.exec() to handle the various issues outlined above. The proposed project should aim at coordinating and learning from these initatives to create and maintain a simple, reusable and well-tested package. Since some of the more problematic platforms are not readily available, it is my hope that the broad Apache community can be a great help."

Some JVMs put restrictions on the total amount of memory available on the heap. If you are getting OutOfMemoryErrors while running Eclipse, the VM can be told to let the heap grow to a larger amount by passing the -vmargs command to the Eclipse launcher. For example, the following command would run Eclipse with a heap size of 256MB: eclipse [normal arguments] -vmargs -Xmx256M [more VM args] The arguments after -vmargs are directly passed to the VM. Run java -X for the list of options your VM accepts. Options starting with -X are implementation-specific and may not be applicable to all VMs. You can also put the extra options in eclipse.ini.

As we have just released the first milestone of the Spring Data JPA project I'd like to give you a quick introduction into its features. As you probably know, the Spring framework provides support to build a JPA based data access layer. So what does Spring Data JPA add to this base support? To answer that question I'd like to start with the data access components for a sample domain implemented using plain JPA + Spring and point out areas that leave room for improvement. After we've done that I will refactor the implementations to use the Spring Data JPA features to address these problem areas. The sample project as well as a step by step guide of the refactoring steps can be found on Github.

Java chief architects are planning to make some changes into current Java version and how updates can bring changes to future of Java application development after Java 9.