· Cross-platform / portability
This is Java's core strengths . Java was designed very focused on migration and cross-platform. For example: Java an int is always 32. Unlike C ++ may be 16, 32, may be based on a predetermined change compiler vendors. In this case transplant procedure will be very troublesome.
·safety
Java is suitable for networking / distributed environment, in order to achieve this goal, put a lot of effort in terms of security, so that Java can easily build anti-virus, anti-tampering system.
· Object-Oriented
Object-oriented programming is a technique well suited for design and development of large-scale software. C ++ to take care of a large number of users and is compatible with the C language C because making itself become the only language C with Classes, how much influence the thoroughness of its object-oriented! Java is a fully object-oriented language.
· Simplicity
Java is a simplified version of C ++ syntax , we can also Java called "C ++ -". Read me "C simple calculations" refers to remove some of the contents of C ++; for example: the file header, pointer arithmetic, structure, union, operator overloading, virtual base class and the like. Also, because the syntax is based on C language, so learning it completely effortless.
·high performance
Java earliest stages of development, always being criticized for "poor performance"; objective, high-level language is always lower than the operating efficiency of low-level language, this can not be avoided. Java language itself developing improved several times by optimizing the efficiency of virtual machines . For example, improve operational efficiency by JIT (JUST IN TIME) time compilation technology. The number of "hot spots" compiled bytecode to native machine code, and the results are cached, recalled when needed. In this case, the Java program execution efficiency greatly improved the efficiency of the reception and even some code in C ++.
Therefore, Java low performance of short legs, has been completely resolved. The development of the industry, we also see a lot of C ++ to Java application development, many C ++ programmers to transition to Java programmers.
·distributed
Java is designed for the distributed environment of the Internet, because it can handle TCP / IP protocol. In fact, the URL to access a network resource and access local files is as simple. Also supports Java Remote Method Invocation (RMI, Remote Method Invocation), the program can invoke methods across the network.
·Multithreading
Multi-threaded use can lead to better interactive response and real-time behavior . The simplicity of Java multi-threaded Java is one of the main reasons the mainstream server-side development language.
· Robustness
Java is a robust language, absorb the advantages of C / C ++ language, but removed some of the impact robustness program (such as: pointer, application and release of memory, etc.). Java programs can not cause the computer to crash. Even if the Java program may have errors. If some unexpected things occur, the program will not collapse, but rather the exception is thrown, then it is dealt with through an exception handling mechanism.
