Overview Java Programming Language
1. Introduce Java Programming Language
Java is one of the powerful programming languages and is used in large software development, web pages, games or applications on mobile devices, the Java programming language has become stronger ever. This article would like to present some typical characteristics of the Java programming language so that you get an overview of this language.
2. What makes Java can be so powerful?
Unlike other programming languages such as C/C++, .Net,… Java is not compile the source code direct to machine code but only compiled into bytecode, then the Java Virtual Machine will transcoding bytecode into code can execute, depending on the operating system currently running java virtual machine, so all application java want to running, ask your computer must be installed java virtual machine. This gives strength to java but also makes the speed of Java applications run slower than compiled other languages. However, this level is not significantly slow and acceptable.
3. Features of the Java programming language
3.1. Object-oriented programming Language.
Java language is object-oriented programming, is built on the platform C++, but Java has been eliminated the syntax complex of C++ and the pointer operators… this makes Java quite easy to learn than C/C++, the removal of arithmetic, Java also limited by the deep intervention into the system programmer, bring higher security capabilities.
3.2. Independent of hardware and operating systems.
A program written in Java can run well in many different environments, called “cross-platform”. The ability independent of hardware and operating systems are shown in two levels: source code level and binary level.
Source code level: data type in Java is consistent for all operating systems and different hardware. Java has its own set of libraries to support this issue. Programs written in Java language can compile on different types of machines without an error.
Binary level: A compiled code can run on many different platforms without compiling source code. However, need Java Virtual Machine to compile this code.
3.3. Mechanism of automatic garbage collection.
If you have worked with other programming languages, especially C, C++. the allocated memory is not used anymore after, we need to call command frees memory explicitly to ensure no loss of memory, this is quite a headache for developers, because when developing large applications, the memory management is sometimes quite difficult especially with the beginners.
However with Java, you do not need to worry about this anymore because Java has automatic garbage collection mechanism for the allocated memory area without any reference to another object, the system will free Java this helps your memory.
3.4 Ability Multi-thread
Java supports the ability to handle multiple processes (multithread), it help you execute multiple different tasks in the same time, providing the highest performance for applications, with the ability to sync between processes present.
3.5. Safety and security
Safety: Java programming language requires strict data types
- Data must be declared explicitly.
- Do not use pointers and pointer arithmetic.
- Java control the access strictly to the array, string. Not allowed to use the overflow techniques. Therefore the access will not exceed the size of the array or string.
- The process of allocating and freeing memory is done automatically.
- Error handling mechanism to help the handling and error recovery easier.
Security: Java provides an environmental management program with
- Level 1: Only can access the data and method through which interface of the class provides.
- Level 2: The compiler control code with the rules of the Java programming language before compile code.
- Level 3: The compiler will check the byte code view this code to ensure regulations and rules before implementation.
- Level 4: controlling the loading Java classes into memory to monitor the violation of restricted access to the system before loading into system