入门指南：探索Java EE平台

需积分: 10 52 浏览量更新于2024-07-26 收藏 362KB PDF 举报

"Java发展简介，涵盖数据库和游戏开发，主要介绍Java EE平台入门教程" 本文将探讨Java的发展历程，特别是在数据库和游戏开发领域的应用，同时深入讲解Java Enterprise Edition（Java EE）平台的基础知识，适合对Java编程感兴趣的初学者。 Java自1995年发布以来，已经成为了全球最广泛使用的编程语言之一。它以其“一次编写，到处运行”的跨平台特性，为企业级应用开发提供了强大的支持。在数据库领域，Java与SQL的结合使得开发者能够构建复杂的数据驱动应用，如Java Persistence API (JPA) 和Hibernate框架，它们简化了对象关系映射，提高了开发效率。在游戏开发中，Java也扮演着重要角色。Java的性能优化和稳定性使其成为移动游戏开发的首选，例如Android平台大量使用Java进行应用开发。通过JavaFX和LibGDX等库，开发者可以创建丰富的2D和3D图形游戏。此外，Java的多线程能力使得在处理游戏逻辑和用户交互时更为流畅。 Java EE是Java平台的企业版，它提供了一系列服务和APIs，用于构建分布式、可扩展的Web应用。本教程《YourFirstCup: An Introduction to the Java EE Platform》旨在引导初学者了解这一平台。Java EE包括Servlet、JSP（JavaServer Pages）、EJB（Enterprise JavaBeans）、JMS（Java Message Service）以及JSF（JavaServer Faces）等技术，这些技术为构建企业级应用提供了全面的解决方案。教程中的“sample code”部分是根据Berkeley许可证提供的，允许用户学习和研究，但不能用于商业目的或未经许可的分发。这些示例代码有助于实践和理解Java EE平台的各种组件和工作原理。 Java语言及其企业版在IT行业中的地位不容忽视，无论是在传统的数据库应用还是新兴的游戏开发领域，都有广泛的应用。对于希望踏入这个领域的学习者，理解和掌握Java，尤其是Java EE平台的基本概念和实践，是至关重要的一步。

developers, do not understand how the diferent platforms relate to each other.

The Java Programming Language Platforms

There are four platforms of the Java programming language:

■ Java Platform, Standard Edition (Java SE)

■ Java Platform, Enterprise Edition (Java EE)

■ Java Platform, Micro Edition (Java ME)

■ JavaFX

All Java platforms consist of a Java Virtual Machine (VM) and an application programming

interface (API). The Java Virtual Machine is a program, for a particular hardware and software

platform, that runs Java technology applications. An API is a collection of software components

that you can use to create other software components or applications. Each Java platform

provides a virtual machine and an API, and this allows applications written for that platform to

run on any compatible system with all the advantages of the Java programming language:

platform-independence, power, stability, ease-of-development, and security.

C H A P T E R 2

11Java SE

When most people think of the Java programming language, they think of the Java SE API. Java

SE's API provides the core functionality of the Java programming language. It deines

everything from the basic types and objects of the Java programming language to high-level

classes that are used for networking, security, database access, graphical user interface (GUI)

development, and XML parsing.

In addition to the core API, the Java SE platform consists of a virtual machine, development

tools, deployment technologies, and other class libraries and toolkits commonly used in Java

technology applications.

Java EE

The Java EE platform is built on top of the Java SE platform. The Java EE platform provides an

API and runtime environment for developing and running large-scale, multi-tiered, scalable,

reliable, and secure network applications.

Java ME

The Java ME platform provides an API and a small-footprint virtual machine for running Java

programming language applications on small devices, like mobile phones. The API is a subset of

the Java SE API, along with special class libraries useful for small device application

development. Java ME applications are often clients of Java EE platform services.

JavaFX

JavaFX is a platform for creating rich internet applications using a lightweight user-interface

API. JavaFX applications use hardware-accelerated graphics and media engines to take

advantage of higher-performance clients and a modern look-and-feel as well as high-level APIs

for connecting to networked data sources. JavaFX applications may be clients of Java EE

platform services.

Overview of Enterprise Applications

This section describes enterprise applications and how they are designed and developed.

As stated above, the Java EE platform is designed to help developers create large-scale,

multi-tiered, scalable, reliable, and secure network applications. A shorthand name for such

applications is “enterprise applications,” so called because these applications are designed to

solve the problems encountered by large enterprises. Enterprise applications are not only useful

for large corporations, agencies, and governments, however. The beneits of an enterprise

application are helpful, even essential, for individual developers and small organizations in an

increasingly networked world.

Overview of Enterprise Applications

12 Your First Cup: An Introduction to the Java EE Platform • April 2012The features that make

enterprise applications powerful, like security and reliability, often make

these applications complex. The Java EE platform is designed to reduce the complexity of

enterprise application development by providing a development model, API, and runtime

environment that allows developers to concentrate on functionality.

Tiered Applications

In a multi-tiered application, the functionality of the application is separated into isolated

functional areas, called tiers. Typically, multi-tiered applications have a client tier, a middle tier,

and a data tier (often called the enterprise information systems tier). The client tier consists of a

client program that makes requests to the middle tier. The middle tier's business functions

handle client requests and process application data, storing it in a permanent datastore in the

data tier.

Java EE application development concentrates on the middle tier to make enterprise application

management easier, more robust, and more secure.

The Client Tier

The client tier consists of application clients that access a Java EE server and that are usually

located on a diferent machine from the server. The clients make requests to the server. The

server processes the requests and returns a response back to the client. Many diferent types of

applications can be Java EE clients, and they are not always, or even often Java applications.

Clients can be a web browser, a standalone application, or other servers, and they run on a

diferent machine from the Java EE server.

TheWeb Tier

The web tier consists of components that handle the interaction between clients and the

business tier. Its primary tasks are the following:

■ Dynamically generate content in various formats for the client.

■ Collect input from users of the client interface and return appropriate results from the

components in the business tier.

■ Control the low of screens or pages on the client.

■ Maintain the state of data for a user's session.

■ Perform some basic logic and hold some data temporarily in JavaBeans components.

Java EE Technologies Used in the Web Tier

The following Java EE technologies are used in the web tier in Java EE applications.

Overview of Enterprise Applications

Chapter 2 • Understanding Java Platform, Enterprise Edition 13TABLE 2–1 Web-Tier Java EE

Technologies

Technology Purpose

Servlets Java programming language classes that dynamically

process requests and construct responses, usually for

剩余37页未读，继续阅读

u010196627

粉丝: 0
资源: 1

入门指南：探索Java EE平台

Java发展简介Java发展简介.doc

java技术简介

Java简介和发展Java简介和发展.doc

Java简介

Core Java学习1（java简介与发展史）

Java语言简介

简介Java

关于java的简介

JAVA3D简介.JAVA3D简介.JAVA3D简介.JAVA3D简介.

"JDK8新特性及Java发展历史简介

最新资源