Lesson: The Java Technology Phenomenon
About the Java Technology
Java technology is both a programming language and a platform. It offers a versatile and powerful environment for developing various applications. In this lesson, we will explore the Java programming language and the Java platform, understanding their unique characteristics and benefits.
The Java Programming Language
The Java programming language is renowned for its simplicity and ease of use. It provides developers with a high-level language that allows for efficient and intuitive coding. The following buzzwords encapsulate the key features of the Java language:
1. Simple: The Java language emphasizes simplicity, making it easier to write and understand code.
2. Architecture neutral: Java is designed to be architecture neutral, enabling programs to run on different systems without modification.
3. Object-oriented: Java follows an object-oriented paradigm, promoting modular and reusable code through objects and classes.
4. Portable: Java's platform independence allows programs to run on any system that supports the Java Virtual Machine (JVM).
5. Distributed: Java enables the development of distributed applications, allowing components to communicate across different networks.
6. High performance: Despite being an interpreted language, Java exhibits high performance through advanced optimization techniques.
7. Interpreted: Java programs are both compiled and interpreted. The initial compilation produces Java bytecodes, which are then executed by the interpreter.
8. Multithreaded: Java supports multithreading, enabling concurrent execution of multiple threads within a single program.
9. Robust: Java promotes robustness by providing strong compile-time checking, exception handling, and automatic memory management.
10. Dynamic: Java supports dynamic class loading and dynamic method invocation, allowing flexibility and adaptability in program execution.
11. Secure: Java incorporates built-in security mechanisms to protect against unauthorized access and malicious code execution.
These buzzwords collectively contribute to the strength and versatility of the Java programming language. For a more in-depth understanding of these concepts, you can refer to "The Java Language Environment," a white paper authored by James Gosling and Henry McGilton.
The Java Platform
A platform refers to the hardware or software environment in which a program runs. Unlike many other platforms, the Java platform is unique in that it is a software-only platform that runs on top of various hardware-based platforms.
The Java platform comprises two essential components:
1. Java Virtual Machine (Java VM): The Java VM is the foundation of the Java platform. It provides an execution environment for Java bytecodes, allowing programs to run on different hardware platforms.
2. Java Application Programming Interface (Java API): The Java API is a comprehensive collection of software components that offer a wide range of functionality. It includes libraries and packages that facilitate tasks such as GUI development and network communication.
The Java API is organized into packages, which group related classes and interfaces together. These packages provide developers with a rich set of tools and resources to simplify application development.
The following diagram illustrates the Java platform, depicting how the Java API and the Java VM work together to insulate the program from the underlying hardware.
The Java platform's architecture enables write-once-run-anywhere capability. By compiling programs into Java bytecodes, developers can ensure that their applications run on any system with a compatible Java VM. This level of portability allows Java applications to be executed seamlessly across various platforms, including Windows 2000, Linux, Solaris, and MacOS.
Although Java
bytecodes may introduce a slight performance overhead compared to native code, advanced techniques such as smart compilers, well-tuned interpreters, and just-in-time bytecode compilers mitigate this difference. As a result, Java applications can achieve performance levels comparable to native code while maintaining their portability.
In the next section, "What Can Java Technology Do?," we will explore the functionality provided by different packages within the Java API.
Remember that Java technology offers a unique blend of simplicity, portability, and performance, making it a preferred choice for a wide range of applications.
