The Java language is an object-oriented programming language that supports network computing. The Java language absorbs the advantages of the Smalltalk language and the C + + language, and adds other features,
such as support concurrent programming, network communication, and multimedia data control. The main features are as follows:
1) The Java language is the simple Java language syntax that is very close to the C and C + + languages, making it easy for most programmers to learn and use Java. Java, on the other hand, discards those features that are seldom used, difficult to understand, and confusing in C + +.
such as operator overloading, multiple inheritance, and automatic coercion of type conversions. In particular, the Java language does not use pointers and provides automatic scrap collection, which makes it unnecessary for programmers to worry about memory management
2) The Java language is an object-oriented Java language that provides primitives such as classes, interfaces, and inheritance, and for the sake of simplicity, only supports single inheritance between classes, but supports multiple inheritance between interfaces,
and supports the implementation mechanism between the class and the interface (the keyword is implements). The Java language fully supports dynamic binding, while the C + + language uses dynamic binding only for virtual functions. In short, the Java language is a pure object-oriented programming language
3) The Java language is a distributed Java language that supports the development of Internet applications and has a network application programming interface (java.net) in the basic Java application programming interface, which provides a class library for network application programming.
Include URLs, URLConnection, sockets, ServerSocket, and more. The RMI (remote method Activation) Mechanism of Java is also an important tool for developing distributed applications.
4) The Java language is a robust Java strong type mechanism, exception handling, scrap automatic collection, etc. is the Java program robustness is an important guarantee. Discarding pointers is a wise choice for Java. Java's security check mechanism makes Java more robust
5) Java is often used in a network environment, Java provides a security mechanism to prevent malicious code attacks. In addition to the many security features that the Java language has,
Java has a security mechanism (class ClassLoader) for classes downloaded over the network, such as assigning different namespaces to prevent substitution of local classes with the same name, byte code checking, and providing security management mechanisms (class SecurityManager) for Java applications to set up security Sentinel
6) The Java language is an architecture-neutral Java program (a file with a suffix of Java) that is compiled into an architecture-neutral bytecode format (a file with a suffix of Class) on the Java platform.
It can then be run on any system that implements the Java platform. This approach is suitable for heterogeneous network environment and software distribution
7) The Java language is portable and this portability comes from architecture neutrality, and Java also strictly specifies the length of each basic data type. The Java system itself is also highly portable,
Java compiler is implemented in Java, Java operating environment is implemented with ANSI C
8) The Java language is interpreted as described earlier, Java programs are compiled into bytecode format on the Java platform and can then be run on any system that implements the Java platform. At run time,
These bytecode are interpreted by the Java interpreter in the Java platform, and the classes required during execution are loaded into the runtime environment during the join phase
9) Java is high performance compared to those advanced scripting languages that are interpreted, Java is really high performance. In fact, the speed of Java is getting closer to C + + with the development of JIT (just-in-time) compiler technology.
Ten) The Java language is multithreaded in the Java language, a thread is a special object that must be created by the thread class or its child (grandchild) class. There are usually two ways to create a thread: one,
The constructor using the type thread (Runnable) wraps an object that implements the Runnable interface into one thread, and second, derives the subclass from the thread class and overrides the Run method, and the object created with the subclass is a thread.
It is important to note that the thread class has implemented the Runnable interface, so any thread has its run method, and the Run method contains the code that the thread wants to run. The activity of a thread is controlled by a set of methods.
The Java language supports simultaneous execution of multiple threads and provides a synchronization mechanism between multithreading (the keyword is synchronized)
One ) The Java language is a dynamic Java language designed to accommodate dynamic changes in the environment. The classes required by the Java program can be dynamically loaded into the runtime environment, or they can be loaded into the network to load the required classes.
This also facilitates software upgrades. In addition, classes in Java have a run-time representation that enables type checking at run time
A detailed description of Java language features