Java overview
java中文参考手册
java中文参考手册Java是一种广泛应用于各种领域的编程语言，它具有跨平台、面向对象、高效等特点。
自1995年由Sun公司推出以来，Java在全球范围内得到了众多开发者的喜爱。
本手册将为您介绍Java的基本概念、编程技巧以及相关工具和资源。
一、Java简介与历史Java语言诞生于1995年，由詹姆斯·高斯林领导的研究团队开发。
Java的初衷是为了解决C++语言中复杂、易错、低效的问题，设计出一门简单、安全、高效的编程语言。
Sun公司（已被甲骨文公司收购）将其作为核心产品推广，并逐步发展出Java虚拟机（JVM）、Java企业版（J2EE）等系列技术。
二、Java编程基础1.数据类型与变量：Java中有基本数据类型（如int、float、double、boolean等）和引用数据类型（如类、数组和接口）。
变量是用于存储数据的标识符，需要声明其数据类型和初始值。
2.运算符与表达式：Java支持算术、关系、逻辑等运算符，以及赋值、条件、逗号等表达式。
3.控制结构：Java的控制结构包括顺序、分支（如if、switch）和循环（如for、while、do-while）等。
4.函数与方法：函数是一段封装了特定功能的代码，可以通过参数和返回值与调用者进行交互。
方法是类中定义的功能模块，可以用于执行特定操作。
三、Java面向对象编程1.类与对象：类是面向对象编程的基本单元，包含属性和方法。
对象是类的实例，通过创建对象，我们可以调用类中定义的方法来实现具体功能。
2.封装、继承与多态：封装是将数据和操作封装在一起，提高代码的可维护性。
继承是子类继承父类的属性和方法。
多态是指子类可以根据需要覆盖或实现父类的方法，使得不同的对象可以以统一的接口进行操作。
3.接口与内部类：接口是一组方法的声明，可以用于定义类之间的契约。
内部类是定义在另一个类内部的类，可以访问外部类的成员。
四、Java常用类库1.字符串操作：Java提供了许多字符串操作方法，如字符串匹配、替换、截取等。
java版的状态机实现
java版的状态机实现状态机适⽤场景：C的操作，需要等到A、B的两个操作(A、B顺序操作)，那就需要在 A、B之间创建⼀个状态机(state machine)，C的操作需要状态机达到某⼀个状态才能进⾏1. Overviewjava版的状态机的原理其实就是java中的枚举类Enum，所以在进⾏状态机设计之前，先学习⼀下（回顾⼀个java Enum）2. Java Enums⼀个简单的例⼦：员⼯请假系统，员⼯到HR那离（submitted）-> 部门领导(Escalated) -> 部门经理(Approved)public enum LeaveRequestState {Submitted,Escalated,Approved}我们可以这样引⽤：LeaveRequestState state = LeaveRequestState.Submitted;java的枚举也可以包含⽅法，我们可以在枚举类中写⼀个抽象⽅法（abstract），这样枚举类中的每个成员都会继承该⽅法，这个就是java 版状态机的核⼼所在public enum LeaveRequestState {Submitted {@Overridepublic String responsiblePerson() {return "Employee";}},Escalated {@Overridepublic String responsiblePerson() {return "Team Leader";}},Approved {@Overridepublic String responsiblePerson() {return "Department Manager";}};public abstract String responsiblePerson();}注意上⾯的逗号，以及抽象⽅法前的分号在下⾯的例⼦中, 我们使⽤上⾯代码中的responsiblePerson()⽅法. 这就是⼀个典型的状态机. 我们想知道"Escalated "的“状态”（实际是审批⼈）, 那就会返回结果 “Team Leader”:LeaveRequestState state = LeaveRequestState.Escalated;assertEquals("Team Leader", state.responsiblePerson());同样的 “Department Manager”:LeaveRequestState state = LeaveRequestState.Approved;assertEquals("Department Manager", state.responsiblePerson());3. State Machines状态机⼜称有限状态机，是⼀个建⽴在抽象机器上的计算模型，这个状态机在给定的时间内，只能有⼀个状态，⽽每⼀个状态⼜可以转换为其他状态（其他状态也是我们⾃⼰定义的）4. Enums as State Machines public enum LeaveRequestState {Submitted {@Overridepublic LeaveRequestState nextState() {return Escalated;}@Overridepublic String responsiblePerson() {return "Employee";}},Escalated {@Overridepublic LeaveRequestState nextState() {return Approved;}@Overridepublic String responsiblePerson() {return "Team Leader";}},Approved {@Overridepublic LeaveRequestState nextState() {return this;}@Overridepublic String responsiblePerson() {return "Department Manager";}};public abstract LeaveRequestState nextState();public abstract String responsiblePerson();}LeaveRequestState state = LeaveRequestState.Submitted; state = state.nextState();assertEquals(LeaveRequestState.Escalated, state);state = state.nextState();assertEquals(LeaveRequestState.Approved, state);state = state.nextState();assertEquals(LeaveRequestState.Approved, state);。
Java 第二章Java语言基础PPT课件
input=new TextField(3);
output=new Label("
");
add(prompt); add(input); ad对d(用ou户tp的ut输);入作响应
}
public boolean action(Event e,Object o)
{ output.setText("you’ve entered
11
2、标识符
在Java编程语言中，标识符是赋予变量、类或方法的名称。变 量、函数、类和对象的名称都是标识符，程序员需要标识和使用的 东西都需要标识符。标识符可从一个字母、下划线（_）或美元符号 （$）开始，随后也可跟数字、字母、下划线或美元符号。标识符是 区分大小写，没有长度限制，可以为标识符取任意长度的名字。
小应用程序不用显示调用init()、action()方法。
7
本章主要内容
2.1 简单JAVA程序介绍 2.2 变量与数据类型 2.3 表达式与运算符
8
一、标识符和关键字
1.关键字 关键字对Java编译器有特殊的含义，它们可标识数据
类型名或程序构造（construct）名。下表列出了在Java 编程语言中使用的关键字。
c=(char)System.in.read();
System.out.println("you've entered character: "+c);
}
}
主函数
接受用户从键盘输入 的一个字符
在显示器上输出字符
4
说明：
每个Java application（java 应用程序）中有且仅有 一个main方法，其方法头为： public static void main(String[] args) main()方法是应用程序的入口。
java 常见注解
java 常见注解Java 中的注解（Annotation）是一种代码标记机制，用于为代码添加元数据。
这些元数据可以在编译时或运行时被处理，用于生成代码、控制程序的运行逻辑或进行其他操作。
Java 提供了一些内置的注解，也支持自定义注解。
以下是一些常见的Java 注解：1.@Override: 用于指示一个方法是重写了父类中的方法。
如果被标记的方法并没有在父类中对应的方法，编译器会报错。
2.@Deprecated: 用于标记一个已过时的方法或类。
编译器会检查是否使用了过时的元素，并给出警告。
3.@SuppressWarnings: 用于抑制编译器警告。
4.@SafeVarargs: 用于声明一个泛型数组或可变参数的方法是类型安全的。
5.@FunctionalInterface: 用于标记一个接口是函数式接口，即该接口只包含一个抽象方法的接口。
6.@NotNull: 用于标注一个参数或返回值不是null。
7.@Nullable: 用于标注一个参数或返回值可以为null。
8.@CheckForNull: 用于检查一个值是否为null。
9.@Tested: 用于标记一个类或方法已经进行了测试。
10.@RunWith(Suite.class)和@Suite: 用于定义一个测试套件，将多个测试类组合在一起执行。
11.@ContextConfiguration: 用于加载Spring 配置文件。
12.@Autowired, @Resource, @Qualifier: 用于Spring 中的依赖注入。
13.@PostConstruct和@PreDestroy: 用于标记在构造函数之后和析构函数之前执行的方法。
14.@Transactional: 用于声明一个方法或类需要进行事务管理。
15.@Component, @Service, @Repository, @Controller: 用于标记Spring 中的组件，分别表示业务逻辑层、数据访问层、数据持久化层和表现层组件。
计算机java外文翻译外文文献英文文献
英文原文:Title: Business Applications of Java. Author: Erbschloe, Michael, Business Applications of Java -- Research Starters Business, 2008DataBase: Research Starters - BusinessBusiness Applications of JavaThis article examines the growing use of Java technology in business applications. The history of Java is briefly reviewed along with the impact of open standards on the growth of the World Wide Web. Key components and concepts of the Java programming language are explained including the Java Virtual Machine. Examples of how Java is being used bye-commerce leaders is provided along with an explanation of how Java is used to develop data warehousing, data mining, and industrial automation applications. The concept of metadata modeling and the use of Extendable Markup Language (XML) are also explained.Keywords Application Programming Interfaces (API's); Enterprise JavaBeans (EJB); Extendable Markup Language (XML); HyperText Markup Language (HTML); HyperText Transfer Protocol (HTTP); Java Authentication and Authorization Service (JAAS); Java Cryptography Architecture (JCA); Java Cryptography Extension (JCE); Java Programming Language; Java Virtual Machine (JVM); Java2 Platform, Enterprise Edition (J2EE); Metadata Business Information Systems > Business Applications of JavaOverviewOpen standards have driven the e-business revolution. Networking protocol standards, such as Transmission Control Protocol/Internet Protocol (TCP/IP), HyperText Transfer Protocol (HTTP), and the HyperText Markup Language (HTML) Web standards have enabled universal communication via the Internet and the World Wide Web. As e-business continues to develop, various computing technologies help to drive its evolution.The Java programming language and platform have emerged as major technologies for performing e-business functions. Java programming standards have enabled portability of applications and the reuse of application components across computing platforms. Sun Microsystems' Java Community Process continues to be a strong base for the growth of the Java infrastructure and language standards. This growth of open standards creates new opportunities for designers and developers of applications and services (Smith, 2001).Creation of Java TechnologyJava technology was created as a computer programming tool in a small, secret effort called "the Green Project" at Sun Microsystems in 1991. The Green Team, fully staffed at 13 people and led by James Gosling, locked themselves away in an anonymous office on Sand Hill Road in Menlo Park, cut off from all regular communications with Sun, and worked around the clock for18 months. Their initial conclusion was that at least one significant trend would be the convergence of digitally controlled consumer devices and computers. A device-independent programming language code-named "Oak" was the result.To demonstrate how this new language could power the future of digital devices, the Green Team developed an interactive, handheld home-entertainment device controller targeted at the digital cable television industry. But the idea was too far ahead of its time, and the digital cable television industry wasn't ready for the leap forward that Java technology offered them. As it turns out, the Internet was ready for Java technology, and just in time for its initial public introduction in 1995, the team was able to announce that the Netscape Navigator Internet browser would incorporate Java technology ("Learn about Java," 2007).Applications of JavaJava uses many familiar programming concepts and constructs and allows portability by providing a common interface through an external Java Virtual Machine (JVM). A virtual machine is a self-contained operating environment, created by a software layer that behaves as if it were a separate computer. Benefits of creating virtual machines include better exploitation of powerful computing resources and isolation of applications to prevent cross-corruption and improve security (Matlis, 2006).The JVM allows computing devices with limited processors or memory to handle more advanced applications by calling up software instructions inside the JVM to perform most of the work. This also reduces the size and complexity of Java applications because many of the core functions and processing instructions were built into the JVM. As a result, software developersno longer need to re-create the same application for every operating system. Java also provides security by instructing the application to interact with the virtual machine, which served as a barrier between applications and the core system, effectively protecting systems from malicious code.Among other things, Java is tailor-made for the growing Internet because it makes it easy to develop new, dynamic applications that could make the most of the Internet's power and capabilities. Java is now an open standard, meaning that no single entity controls its development and the tools for writing programs in the language are available to everyone. The power of open standards like Java is the ability to break down barriers and speed up progress.Today, you can find Java technology in networks and devices that range from the Internet and scientific supercomputers to laptops and cell phones, from Wall Street market simulators to home game players and credit cards. There are over 3 million Java developers and now there are several versions of the code. Most large corporations have in-house Java developers. In addition, the majority of key software vendors use Java in their commercial applications (Lazaridis, 2003).ApplicationsJava on the World Wide WebJava has found a place on some of the most popular websites in the world and the uses of Java continues to grow. Java applications not only provide unique user interfaces, they also help to power the backend of websites. Two e-commerce giants that everybody is probably familiar with (eBay and Amazon) have been Java pioneers on the World Wide Web.eBayFounded in 1995, eBay enables e-commerce on a local, national and international basis with an array of Web sites-including the eBay marketplaces, PayPal, Skype, and -that bring together millions of buyers and sellers every day. You can find it on eBay, even if you didn't know it existed. On a typical day, more than 100 million items are listed on eBay in tens of thousands of categories. Recent listings have included a tunnel boring machine from the Chunnel project, a cup of water that once belonged to Elvis, and the Volkswagen that Pope Benedict XVI owned before he moved up to the Popemobile. More than one hundred million items are available at any given time, from the massive to the miniature, the magical to the mundane, on eBay; the world's largest online marketplace.eBay uses Java almost everywhere. To address some security issues, eBay chose Sun Microsystems' Java System Identity Manager as the platform for revamping its identity management system. The task at hand was to provide identity management for more than 12,000 eBay employees and contractors.Now more than a thousand eBay software developers work daily with Java applications. Java's inherent portability allows eBay to move to new hardware to take advantage of new technology, packaging, or pricing, without having to rewrite Java code ("eBay drives explosive growth," 2007).Amazon (a large seller of books, CDs, and other products) has created a Web Service application that enables users to browse their product catalog and place orders. uses a Java application that searches the Amazon catalog for books whose subject matches a user-selected topic. The application displays ten books that match the chosen topic, and shows the author name, book title, list price, Amazon discount price, and the cover icon. The user may optionally view one review per displayed title and make a buying decision (Stearns & Garishakurthi, 2003).Java in Data Warehousing & MiningAlthough many companies currently benefit from data warehousing to support corporate decision making, new business intelligence approaches continue to emerge that can be powered by Java technology. Applications such as data warehousing, data mining, Enterprise Information Portals (EIP's), and Knowledge Management Systems (which can all comprise a businessintelligence application) are able to provide insight into customer retention, purchasing patterns, and even future buying behavior.These applications can not only tell what has happened but why and what may happen given certain business conditions; allowing for "what if" scenarios to be explored. As a result of this information growth, people at all levels inside the enterprise, as well as suppliers, customers, and others in the value chain, are clamoring for subsets of the vast stores of information such as billing, shipping, and inventory information, to help them make business decisions. While collecting and storing vast amounts of data is one thing, utilizing and deploying that data throughout the organization is another.The technical challenges inherent in integrating disparate data formats, platforms, and applications are significant. However, emerging standards such as the Application Programming Interfaces (API's) that comprise the Java platform, as well as Extendable Markup Language (XML) technologies can facilitate the interchange of data and the development of next generation data warehousing and business intelligence applications. While Java technology has been used extensively for client side access and to presentation layer challenges, it is rapidly emerging as a significant tool for developing scaleable server side programs. The Java2 Platform, Enterprise Edition (J2EE) provides the object, transaction, and security support for building such systems.Metadata IssuesOne of the key issues that business intelligence developers must solve is that of incompatible metadata formats. Metadata can be defined as information about data or simply "data about data." In practice, metadata is what most tools, databases, applications, and other information processes use to define, relate, and manipulate data objects within their own environments. It defines the structure and meaning of data objects managed by an application so that the application knows how to process requests or jobs involving those data objects. Developers can use this schema to create views for users. Also, users can browse the schema to better understand the structure and function of the database tables before launching a query.To address the metadata issue, a group of companies (including Unisys, Oracle, IBM, SAS Institute, Hyperion, Inline Software and Sun) have joined to develop the Java Metadata Interface (JMI) API. The JMI API permits the access and manipulation of metadata in Java with standard metadata services. JMI is based on the Meta Object Facility (MOF) specification from the Object Management Group (OMG). The MOF provides a model and a set of interfaces for the creation, storage, access, and interchange of metadata and metamodels (higher-level abstractions of metadata). Metamodel and metadata interchange is done via XML and uses the XML Metadata Interchange (XMI) specification, also from the OMG. JMI leverages Java technology to create an end-to-end data warehousing and business intelligence solutions framework.Enterprise JavaBeansA key tool provided by J2EE is Enterprise JavaBeans (EJB), an architecture for the development of component-based distributed business applications. Applications written using the EJB architecture are scalable, transactional, secure, and multi-user aware. These applications may be written once and then deployed on any server platform that supports J2EE. The EJB architecture makes it easy for developers to write components, since they do not need to understand or deal with complex, system-level details such as thread management, resource pooling, and transaction and security management. This allows for role-based development where component assemblers, platform providers and application assemblers can focus on their area of responsibility further simplifying application development.EJB's in the Travel IndustryA case study from the travel industry helps to illustrate how such applications could function. A travel company amasses a great deal of information about its operations in various applications distributed throughout multiple departments. Flight, hotel, and automobile reservation information is located in a database being accessed by travel agents worldwide. Another application contains information that must be updated with credit and billing historyfrom a financial services company. Data is periodically extracted from the travel reservation system databases to spreadsheets for use in future sales and marketing analysis.Utilizing J2EE, the company could consolidate application development within an EJB container, which can run on a variety of hardware and software platforms allowing existing databases and applications to coexist with newly developed ones. EJBs can be developed to model various data sets important to the travel reservation business including information about customer, hotel, car rental agency, and other attributes.Data Storage & AccessData stored in existing applications can be accessed with specialized connectors. Integration and interoperability of these data sources is further enabled by the metadata repository that contains metamodels of the data contained in the sources, which then can be accessed and interchanged uniformly via the JMI API. These metamodels capture the essential structure and semantics of business components, allowing them to be accessed and queried via the JMI API or to be interchanged via XML. Through all of these processes, the J2EE infrastructure ensures the security and integrity of the data through transaction management and propagation and the underlying security architecture.To consolidate historical information for analysis of sales and marketing trends, a data warehouse is often the best solution. In this example, data can be extracted from the operational systems with a variety of Extract, Transform and Load tools (ETL). The metamodels allow EJBsdesigned for filtering, transformation, and consolidation of data to operate uniformly on datafrom diverse data sources as the bean is able to query the metamodel to identify and extract the pertinent fields. Queries and reports can be run against the data warehouse that contains information from numerous sources in a consistent, enterprise-wide fashion through the use of the JMI API (Mosher & Oh, 2007).Java in Industrial SettingsMany people know Java only as a tool on the World Wide Web that enables sites to perform some of their fancier functions such as interactivity and animation. However, the actual uses for Java are much more widespread. Since Java is an object-oriented language like C++, the time needed for application development is minimal. Java also encourages good software engineering practices with clear separation of interfaces and implementations as well as easy exception handling.In addition, Java's automatic memory management and lack of pointers remove some leading causes of programming errors. Most importantly, application developers do not need to create different versions of the software for different platforms. The advantages available through Java have even found their way into hardware. The emerging new Java devices are streamlined systems that exploit network servers for much of their processing power, storage, content, and administration.Benefits of JavaThe benefits of Java translate across many industries, and some are specific to the control and automation environment. For example, many plant-floor applications use relatively simple equipment; upgrading to PCs would be expensive and undesirable. Java's ability to run on any platform enables the organization to make use of the existing equipment while enhancing the application.IntegrationWith few exceptions, applications running on the factory floor were never intended to exchange information with systems in the executive office, but managers have recently discovered the need for that type of information. Before Java, that often meant bringing together data from systems written on different platforms in different languages at different times. Integration was usually done on a piecemeal basis, resulting in a system that, once it worked, was unique to the two applications it was tying together. Additional integration required developing a brand new system from scratch, raising the cost of integration.Java makes system integration relatively easy. Foxboro Controls Inc., for example, used Java to make its dynamic-performance-monitor software package Internet-ready. This software provides senior executives with strategic information about a plant's operation. The dynamic performance monitor takes data from instruments throughout the plant and performs variousmathematical and statistical calculations on them, resulting in information (usually financial) that a manager can more readily absorb and use.ScalabilityAnother benefit of Java in the industrial environment is its scalability. In a plant, embedded applications such as automated data collection and machine diagnostics provide critical data regarding production-line readiness or operation efficiency. These data form a critical ingredient for applications that examine the health of a production line or run. Users of these devices can take advantage of the benefits of Java without changing or upgrading hardware. For example, operations and maintenance personnel could carry a handheld, wireless, embedded-Java device anywhere in the plant to monitor production status or problems.Even when internal compatibility is not an issue, companies often face difficulties when suppliers with whom they share information have incompatible systems. This becomes more of a problem as supply-chain management takes on a more critical role which requires manufacturers to interact more with offshore suppliers and clients. The greatest efficiency comes when all systems can communicate with each other and share information seamlessly. Since Java is so ubiquitous, it often solves these problems (Paula, 1997).Dynamic Web Page DevelopmentJava has been used by both large and small organizations for a wide variety of applications beyond consumer oriented websites. Sandia, a multiprogram laboratory of the U.S. Department of Energy's National Nuclear Security Administration, has developed a unique Java application. The lab was tasked with developing an enterprise-wide inventory tracking and equipment maintenance system that provides dynamic Web pages. The developers selected Java Studio Enterprise 7 for the project because of its Application Framework technology and Web Graphical User Interface (GUI) components, which allow the system to be indexed by an expandable catalog. The flexibility, scalability, and portability of Java helped to reduce development timeand costs (Garcia, 2004)IssueJava Security for E-Business ApplicationsTo support the expansion of their computing boundaries, businesses have deployed Web application servers (WAS). A WAS differs from a traditional Web server because it provides a more flexible foundation for dynamic transactions and objects, partly through the exploitation of Java technology. Traditional Web servers remain constrained to servicing standard HTTP requests, returning the contents of static HTML pages and images or the output from executed Common Gateway Interface (CGI ) scripts.An administrator can configure a WAS with policies based on security specifications for Java servlets and manage authentication and authorization with Java Authentication andAuthorization Service (JAAS) modules. An authentication and authorization service can bewritten in Java code or interface to an existing authentication or authorization infrastructure. Fora cryptography-based security infrastructure, the security server may exploit the Java Cryptography Architecture (JCA) and Java Cryptography Extension (JCE). To present the user with a usable interaction with the WAS environment, the Web server can readily employ a formof "single sign-on" to avoid redundant authentication requests. A single sign-on preserves user authentication across multiple HTTP requests so that the user is not prompted many times for authentication data (i.e., user ID and password).Based on the security policies, JAAS can be employed to handle the authentication process with the identity of the Java client. After successful authentication, the WAS securitycollaborator consults with the security server. The WAS environment authentication requirements can be fairly complex. In a given deployment environment, all applications or solutions may not originate from the same vendor. In addition, these applications may be running on different operating systems. Although Java is often the language of choice for portability between platforms, it needs to marry its security features with those of the containing environment.Authentication & AuthorizationAuthentication and authorization are key elements in any secure information handling system. Since the inception of Java technology, much of the authentication and authorization issues have been with respect to downloadable code running in Web browsers. In many ways, this had been the correct set of issues to address, since the client's system needs to be protected from mobile code obtained from arbitrary sites on the Internet. As Java technology moved from a client-centric Web technology to a server-side scripting and integration technology, it required additional authentication and authorization technologies.The kind of proof required for authentication may depend on the security requirements of a particular computing resource or specific enterprise security policies. To provide such flexibility, the JAAS authentication framework is based on the concept of configurable authenticators. This architecture allows system administrators to configure, or plug in, the appropriate authenticatorsto meet the security requirements of the deployed application. The JAAS architecture also allows applications to remain independent from underlying authentication mechanisms. So, as new authenticators become available or as current authentication services are updated, system administrators can easily replace authenticators without having to modify or recompile existing applications.At the end of a successful authentication, a request is associated with a user in the WAS user registry. After a successful authentication, the WAS consults security policies to determine if the user has the required permissions to complete the requested action on the servlet. This policy canbe enforced using the WAS configuration (declarative security) or by the servlet itself (programmatic security), or a combination of both.The WAS environment pulls together many different technologies to service the enterprise. Because of the heterogeneous nature of the client and server entities, Java technology is a good choice for both administrators and developers. However, to service the diverse security needs of these entities and their tasks, many Java security technologies must be used, not only at a primary level between client and server entities, but also at a secondary level, from served objects. By using a synergistic mix of the various Java security technologies, administrators and developers can make not only their Web application servers secure, but their WAS environments secure as well (Koved, 2001).ConclusionOpen standards have driven the e-business revolution. As e-business continues to develop, various computing technologies help to drive its evolution. The Java programming language and platform have emerged as major technologies for performing e-business functions. Java programming standards have enabled portability of applications and the reuse of application components. Java uses many familiar concepts and constructs and allows portability by providing a common interface through an external Java Virtual Machine (JVM). Today, you can find Java technology in networks and devices that range from the Internet and scientific supercomputers to laptops and cell phones, from Wall Street market simulators to home game players and credit cards.Java has found a place on some of the most popular websites in the world. Java applications not only provide unique user interfaces, they also help to power the backend of websites. While Java technology has been used extensively for client side access and in the presentation layer, it is also emerging as a significant tool for developing scaleable server side programs.Since Java is an object-oriented language like C++, the time needed for application development is minimal. Java also encourages good software engineering practices with clear separation of interfaces and implementations as well as easy exception handling. Java's automatic memory management and lack of pointers remove some leading causes of programming errors. The advantages available through Java have also found their way into hardware. The emerging new Java devices are streamlined systems that exploit network servers for much of their processing power, storage, content, and administration.中文翻译:标题：Java的商业应用。
Java项目管理工具有哪些值得推荐
Java项目管理工具有哪些值得推荐在当今的软件开发领域，Java 依然是广泛使用的编程语言之一。
对于 Java 项目的成功开发和管理，选择合适的工具至关重要。
接下来，让我们一起探索一些值得推荐的 Java 项目管理工具。
一、MavenMaven 是一个强大的项目管理和构建工具。
它通过一个标准化的项目结构和配置文件（pomxml），帮助开发者管理项目的依赖、编译、测试、打包和部署等流程。
Maven 的依赖管理功能十分出色。
开发者只需在 pomxml 中声明项目所需的依赖库及其版本，Maven 就会自动从中央仓库下载并管理这些依赖，确保项目的构建环境一致且可靠。
它还提供了丰富的插件，用于执行各种任务，如代码质量检查、生成文档等。
Maven 的命令行操作简单直观，便于开发者在不同的开发环境中进行项目的构建和管理。
二、GradleGradle 是一个基于 Groovy 或 Kotlin 脚本的灵活的构建工具。
与Maven 相比，Gradle 具有更强大的自定义能力和更简洁的配置语法。
Gradle 同样能够管理项目依赖，并支持多种项目类型，如 Java 项目、Android 项目等。
它的任务执行机制非常高效，可以根据项目的实际情况智能地优化构建过程。
Gradle 还可以与其他工具和技术进行很好的集成，例如持续集成工具（如 Jenkins）和版本控制系统（如 Git）。
三、Git作为分布式版本控制系统，Git 在 Java 项目管理中扮演着不可或缺的角色。
它允许开发者在本地进行版本控制，随时提交代码更改，并能够方便地与团队成员共享和合并代码。
Git 的分支管理功能使得开发者可以并行开发不同的功能或修复不同的问题，而不会相互干扰。
通过合并分支，可以将各个开发分支的成果整合到主分支中。
此外，Git 与众多代码托管平台（如 GitHub、GitLab 等）相集成，方便团队协作和项目代码的存储与共享。
四、JIRAJIRA 是一款流行的项目管理和问题跟踪工具。
java常用的英语单词
java常用的英语单词
以下是10 个Java 中常用的英语单词及其意思：
1. Object（对象）：在Java 中，一切皆对象。
对象是类的实例，它包含数据和操作这些数据的方法。
2. Class（类）：类是对象的模板，它定义了对象的属性和方法。
3. Interface（接口）：接口是一种特殊的类，它只包含方法的声明，而没有方法的实现。
4. Package（包）：包是一种组织类和接口的方式，它将相关的类和接口组织在一起，以便更好地管理和使用。
5. inheritance（继承）：继承是指一个类可以从另一个类中继承属性和方法。
6. Polymorphism（多态性）：多态性是指不同的对象可以对同一方法进行不同的实现。
7. Encapsulation（封装）：封装是指将对象的属性和方法封装在一起，只对外公开必要的接口。
8. Abstraction（抽象）：抽象是指从具体的事物中提取出共同的特征和行为，形成一个抽象的概念。
9. Thread（线程）：线程是程序中的执行单元，它可以并发地执行任务。
10. Exception（异常）：异常是程序执行过程中出现的错误情况，Java 提供了异常处理机制来处理这些错误。
JAVA编程常用英文单词汇总
Java根底常见英语词汇(共70个)OO: object-oriented ,面向对象OOP: object-oriented programming,面向对象编程JDK:Java development kit, java开发工具包JVM:java virtual machine ,java虚拟机Compile:编绎Run:运行Class:类Object:对象System:系统out:输出print:打印line:行variable:变量type:类型operation:操作,运算array:数组parameter:参数method:方法function:函数member-variable:成员变量member-function:成员函数get:得到set:设置public:公有的private:私有的protected:受保护的default:默认access:访问package:包import:导入static:静态的void:无(返回类型)extends:继承parent class:父类base class:基类super class:超类child class:子类derived class:派生类override:重写,覆盖overload:重载final:最终的,不能改变的abstract:抽象interface:接口implements:实现exception:异常Runtime:运行时ArithmeticException:算术异常ArrayIndexOutOfBoundsException:数组下标越界异常NullPointerException:空引用异常ClassNotFoundException:类没有发现异常NumberFormatException:数字格式异常(字符串不能转化为数字) Catch:捕捉Finally:最后Throw:抛出Throws: (投掷)表示强制异常处理Throwable:(可抛出的)表示所有异常类的祖先类Lang:language,语言Util:工具 Display:显示Random:随机Collection:集合ArrayList:(数组列表)表示动态数组HashMap: 散列表,哈希表Swing:轻巧的Awt:abstract window toolkit:抽象窗口工具包Frame:窗体Size:尺寸Title:标题Add:添加Panel:面板Layout:布局Scroll:滚动Vertical:垂直Horizonatal:水平Label:标签TextField:文本框TextArea:文本域Button:按钮Checkbox:复选框Radiobutton:单项选择按钮Combobox:复选框Event:事件Mouse:鼠标Key:键Focus:焦点Listener:监听Border:边界Flow:流Grid:网格MenuBar:菜单栏Menu:菜单MenuItem:菜单项PopupMenu:弹出菜单Dialog:对话框Message:消息 Icon:图标Tree:树Node:节点Jdbc:java database connectivity, java数据库连接DriverManager:驱动管理器Connection:连接Statement:表示执行对象Preparedstatement:表示预执行对象Resultset:结果集Next:下一个Close:关闭executeQuery:执行查询Jbuilder中常用英文(共33个)File:文件New:新建New Project:新建工程New Class: 新建类New File:新建文件Open project:翻开工程Open file:翻开文件Reopen:重新翻开Close projects:关闭工程Close all except…:除了..全部关闭Rename:重命名Exit:退出View:视图Panes:面板组Project:工程Content:内容Structure:结构Message:消息Source:源文件Bean:豆子Properties:属性Make:编绎Build:编绎Rebuild:重编绎Refresh:刷新Project properties:工程属性Default project properties:默认的工程属性Run:运行Debug:调试Tools:工具Preferences:参数配置Configure:配置Libraries:库JSP中常用英文URL: Universal Resource Location:统一资源定位符IE: Internet Explorer 因特网浏览器Model:模型View:视图C:controller:控制器Tomcat:一种jsp的web效劳器WebModule:web模块Servlet:小效劳程序Request:请求Response:响应Init: initialize,初始化Service:效劳Destroy:销毁Startup:启动Mapping:映射pattern:模式Getparameter:获取参数Session:会话Application:应用程序Context:上下文redirect:重定向dispatch:分发forward:转交setAttribute:设置属性getAttribute:获取属性page:页面contentType:内容类型charset:字符集include:包含tag:标签taglib:标签库EL:expression language,表达式语言Scope:作用域Empty:空JSTL:java standard tag library,java标准标签库TLD:taglib description,标签库描述符Core:核心Test:测试Foreach:表示循环Var:variable,变量Status:状态Items:工程集合Fmt:format,格式化Filter:过滤器报错英文第一章：JDK(Java Development Kit) java开发工具包JVM(Java Virtual Machine) java虚拟机Javac编译命令java解释命令Javadoc生成java文档命令classpath 类路径Version版本author作者public公共的class类static静态的void没有返回值String字符串类System系统类print同行打印println换行打印JIT(just-in-time)及时处理第二章：byte 字节char 字符boolean 布尔short 短整型int 整形long 长整形float 浮点类型double 双精度if 如果else 否那么switch 多路分支case 与常值匹配break 终止default 默认while 当到循环do 直到循环for 次数循环continue结束本次循环进行下次跌代length 获取数组元素个数第三章：OOPobject oriented programming 面向对象编程Object 对象Class 类Class member 类成员Class method类方法Class variable 类变量Constructor 构造方法Package 包Import package 导入包第四章：Extends 继承Base class 基类Super class 超类Overloaded method 重载方法Overridden method 重写方法Public 公有Private 私有Protected 保护Abstract抽象Interface 接口Implements interface 实现接口第五章：Exception 意外，异常RuntimeExcepiton 运行时异常ArithmeticException 算术异常IllegalArgumentException 非法数据异常ArrayIndexOutOfBoundsException 数组索引越界异常NullPointerException 空指针异常ClassNotFoundException 类无法加载异常〔类不能找到〕NumberFormatException 字符串到float类型转换异常〔数字格式异常〕IOException 输入输出异常FileNotFoundException 找不到文件异常EOFException 文件结束异常InterruptedException 〔线程〕中断异常try 尝试catch 捕捉finally 最后throw 投、掷、抛throws 投、掷、抛print Stack Trace() 打印堆栈信息get Message〔〕获得错误消息get Cause〔〕获得异常原因method 方法able 能够instance 实例check 检查第六章：byte〔字节〕char〔字符〕int〔整型〕long〔长整型〕float〔浮点型〕double〔双精度〕boolean〔布尔〕short〔短整型〕Byte 〔字节类〕Character 〔字符类〕Integer〔整型类〕Long 〔长整型类〕Float〔浮点型类〕.Double 〔双精度类〕Boolean〔布尔类〕Short 〔短整型类〕Digit 〔数字〕Letter 〔字母〕Lower (小写)Upper (大写)Space (空格)Identifier (标识符)Start (开始)String (字符串)length 〔值〕equals (等于)Ignore 〔忽略〕compare 〔比拟〕sub 〔提取〕concat 〔连接〕replace 〔替换〕trim 〔整理〕Buffer (缓冲器)reverse (颠倒)delete 〔删除〕append 〔添加〕Interrupted 〔中断的〕第七章：Date 日期，日子After 后来，后面Before 在前，以前Equals 相等，均等toString 转换为字符串SetTime 设置时间Display 显示，展示Calendar 日历Add 添加，增加GetInstance获得实例getTime 获得时间Clear 扫除，去除Clone 克隆，复制Util 工具，龙套Components成分，组成Random 随意，任意Next Int 下一个整数Gaussian 高斯ArrayList 对列.LinkedList链表Hash 无用信息，杂乱信号Map 地图Vector 向量，矢量Size 大小Collection收集Shuffle 混乱，洗牌RemoveFirst移动至开头RemoveLast 移动至最后lastElement最后的元素Capacity 容量，生产量Contains 包含，容纳Search 搜索，查询InsertElementAt 插入元素在某一位置第八章：io->in out 输入/输出File文件import导入exists存在isFile是文件isDirectory 是目录getName获取名字getPath获取路径getAbsolutePath 获取绝对路径lastModified 最后修改日期length长度InputStream 输入流OutputStream 输出流Unicode统一的字符编码标准, 采用双字节对字符进行编码Information 信息FileInputStream 文件输入流FileOutputStream文件输出流IOException 输入输出异常fileobject 文件对象available 可获取的read读取write写BufferedReader 缓冲区读取FileReader 文本文件读取BufferedWriter 缓冲区输出FileWriter 文本文件写出flush清空close关闭DataInputStream 二进制文件读取.DataOutputStream二进制文件写出EOF最后encoding编码Remote远程release释放第九章：JBuiderJava 集成开发环境〔IDE〕Enterprise 企业版Developer 开发版Foundation 根底版Messages 消息格Structure 结构窗格Project工程Files文件Source源代码Design设计History历史Doc文档File文件Edit编辑Search查找Refactor 要素View视图Run运行Tools工具Window窗口Help帮助Vector矢量addElement 添加内容Project Winzard 工程向导Step步骤Title标题Description 描述Copyright 版权Company公司Aptech Limited Aptechauthor 作者Back后退Finish完成version版本Debug调试New新建ErrorInsight 调试第十章：JFrame窗口框架JPanel 面板JScrollPane 滚动面板title 标题Dimension 尺寸Component组件SwingJA V A轻量级组件getContentPane 得到内容面板LayoutManager布局管理器setVerticalScrollBarPolicy设置垂直滚动条策略AWT〔Abstract Window Toolkit〕抽象窗口工具包GUI 〔Graphical User Interface〕图形用户界面VERTICAL_SCROLLEARAS_NEEDED当内容大大面板出现滚动条VERTICAL_SOROLLEARAS_ALWAYS显示滚动条VERTICAL_SOROLLEARAS_NEVER不显示滚动条JLabel标签Icon 图标image图象LEFT 左对齐RIGHT右对齐JTextField单行文本getColumns得到列数setLayout设置布局BorderLayout 边框布局CENTER居中对齐JTextArea多行文本setFont设置字体setHorizontalAlignment设置文本水平对齐方式setDefaultCloseOperation设置默认的关闭操作add增加JButton 按钮JCheckBox 复选框JRadioButton单项选择按钮addItem 增加列表项getItemAt 得到位置的列表项getItemCount 得到列表项个数setRolloverIcon 当鼠标经过的图标setSelectedIcon 中选择按钮的图标getSelectedItem 得到选择的列表项getSelectedIndex 得到选择的索引ActionListener按钮监听ActionEvent 按钮事件actionPerformed按钮单击方法附加.............可能有重复编程英语：(手摘)abstract (关键字) 抽象['?bstr?kt]accessvt.访问,存取['?kses]'(n.入口,使用权)algorithmn.算法['?lg?riem]Annotation[java] 代码注释[?n?u'tei??n]anonymousadj.匿名的[?'n?nim?s]'(反义：directly adv.直接地,立即[di'rektli, dai'rektli]) apply v.应用,适用[?'plai]application n.应用,应用程序[,?pli'kei??n]' (application crash 程序崩溃) arbitrarya.任意的['ɑ:bitr?ri]argument n.参数;争论,论据['ɑ:gjum?nt]'(缩写args)assert (关键字) 断言[?'s?:t] ' (java 1.4 之后成为关键字)associaten.关联(同伴,伙伴) [?'s?u?ieit]attributen.属性(品质,特征) [?'tribju:t]boolean(关键字) 逻辑的, 布尔型call n.v.调用; 呼叫; [k?:l]circumstancen.事件(环境,状况) ['s?:k?mst?ns]crash n.崩溃,破碎[kr??]cohesion 内聚,黏聚,结合[k?u'hi:??n](a class is designed with a single, well-focoused purpose. 应该不止这点)command n. 命令,指令[k?'mɑ:nd](指挥, 控制) (command-line 命令行) Comments [java] 文本注释['k?ments]compile[java] v.编译[k?m'pail]' Compilation n.编辑[,k?mpi'lei??n]const (保存字)constant n. 常量, 常数, 恒量['k?nst?nt]continue (关键字)coupling 耦合,联结['k?pli?]making sure that classes know about other classes only through their APIs.declare[java] 声明[di'kl??]default(关键字) 默认值; 缺省值[di'f?:lt]delimiter定义符; 定界符Encapsulation[java] 封装(hiding implementation details)Exception [java] 例外; 异常[ik'sep??n]entry n.登录项, 输入项, 条目['entri]enum(关键字)execute vt.执行['eksikju:t]exhibit v.显示, 陈列[ig'zibit]exist 存在, 发生[ig'zist] '(SQL关键字exists)extends(关键字) 继承、扩展[ik'stend]false (关键字)final (关键字) finally (关键字)fragments段落; 代码块['fr?gm?nt]FrameWork [java] 结构,框架['freimw?:k]Generic[java] 泛型[d?i'nerik]goto(保存字) 跳转heap n.堆[hi:p]implements(关键字) 实现['implim?nt]import (关键字) 引入(进口,输入)Info n.信息(information [,inf?'mei??n] )Inheritance [java] 继承[in'herit?ns] (遗传,遗产)initialize 预置初始化[i'ni??laiz]instanceof(关键字) 运算符，用于引用变量，以检查这个对象是否是某种类型。
java命令大全
java命令大全在Java中，可以使用许多命令来编译、运行和调试Java程序。
以下是一些常见的Java命令：1. `java`：用于运行Java程序。
例如：`java HelloWorld`将运行名为`HelloWorld`的Java程序。
2. `javac`：用于将Java源代码编译为Java字节码文件。
例如：`javac HelloWorld.java`将编译名为`HelloWorld.java`的Java源代码文件。
3. `jar`：用于创建和管理Java归档文件。
例如：`jar cvf MyJar.jar MyClass.class`将创建一个名为`MyJar.jar`的归档文件，并将`MyClass.class`添加到其中。
4. `javadoc`：用于生成Java文档。
例如：`javadoc MyPackage/*.java`将生成`MyPackage`中所有Java文件的文档。
5. `javap`：用于反汇编Java字节码文件。
例如：`javap MyClass`将显示与名为`MyClass`的类关联的字节码。
6. `jarsigner`：用于对已签名的Java应用程序和程序包进行签名和验证。
例如：`jarsigner -sign MyJar.jar keyAlias`将对`MyJar.jar`进行签名。
7. `jdb`：Java调试器的命令行界面。
例如：`jdb MyProgram`将使用`jdb`调试名为`MyProgram`的Java程序。
8. `jrunscript`：用于在命令行上运行脚本的命令。
例如：`jrunscript MyScript.js`将运行名为`MyScript.js`的JavaScript脚本。
9. `jps`：用于列出当前正在运行的Java进程。
例如：`jps -l`将列出所有Java进程的进程ID和类路径。
这只是一小部分常用的Java命令清单，Java还有许多其他命令用于不同的目的。
java中文参考手册
java中文参考手册摘要：1.Java 简介2.Java 的历史和发展3.Java 的跨平台特性4.Java 的基本语法和数据类型5.Java 的控制结构6.Java 的数组和字符串操作7.Java 的面向对象编程8.Java 的异常处理9.Java 的输入输出流10.Java 的多线程编程11.Java 的网络编程12.Java 的集合框架13.Java 的日期和时间操作14.Java 的图形界面编程15.Java 的异常处理机制16.Java 的文件操作17.Java 的数据库编程18.Java 的Web 开发19.Java 的企业级框架20.Java 的安全机制正文：Java 中文参考手册Java 是一种广泛使用的计算机编程语言，它具有跨平台、面向对象、安全性等特点，被广泛应用于Web 开发、桌面应用开发、移动应用开发等领域。
1.Java 简介Java 由Sun Microsystems 公司于1995 年推出，是一种高级编程语言。
Java 的跨平台特性使得开发的程序可以在不同的操作系统上运行，这主要得益于Java 虚拟机（JVM）的存在。
2.Java 的历史和发展Java 语言的雏形最早出现在1991 年，当时Sun 公司为了在电视遥控器等嵌入式设备上运行游戏而开发了一种名为Oak 的编程语言。
随着技术的进步和需求的变化，Oak 逐渐演变成了Java。
3.Java 的跨平台特性Java 的跨平台特性主要归功于Java 虚拟机（JVM）。
JVM 可以在不同的操作系统上安装，Java 程序通过JVM 解释执行，因此具有很好的跨平台性能。
4.Java 的基本语法和数据类型Java 的语法类似于C++，但摒弃了C++中的一些特性，如指针操作和多重继承。
Java 的数据类型分为基本数据类型和引用数据类型。
5.Java 的控制结构Java 的控制结构包括条件语句（if、else、switch 等）、循环语句（for、while、do-while 等）和分支语句（break、continue、return 等）。
微博需求分析
1.信息聚合、分类、筛选、展示工具
2.潜在好友识别工具
3.互动游戏
4.舆情监测响应工具
5.目标用户识别、筛选、评价工具
6.与优质用户建立联系的工具
7.制造合适内容影响用户的工具
这些只是被分解打散的用户需求，可能存在一些产品形式兼顾以上的多个需求，更高效的发挥微博带来的价值和商机。另一方面，只要深入理解并抓住用户需求的一个方面，做出高度占用户的产品，也能成为微薄上的杀手级应用。
视角四、人对输出型用户的价值
对于输出型用户，他们最大的需求莫过影响力的延伸，即：传播信息并因此影响他人。对于粉丝众多的名人微博，这个可能并不是一个问题。但对于企业用户，他们可能并不具备很高的粉丝量，也可能并不熟悉微博营销，如何推广自己并影响他们的粉丝，就成了一个很大的商机。
对于企业帐号，影响他人可以分为以下几个环节：（1）找到目标用户，（2）与用户建立联系，（3）持续影响他们。以上每个环节，都蕴含着一些商机：如何寻找真正的潜在优质用户；如何与这些优质用户建立联系；如何持续向这些用户输出产品信息和树立企业价形象（品牌）。每个细节都有较好的要求：目标用户的寻找最好很精准；建立用户联系不能太鲁莽；持续影响需要不落俗套，更人性，更优雅。
getGysname()
setGysname(String gysname)
获取、设置id,name,jc,cd,dw,tel,gg,ph,pzwh,memo,gysname
3.
1
a）
b）
c）
d）
e）
2
名称
类型
调用方法
说明
GysTianJiaPanel.java
实现类
jButton1ActionPerformed(java.awt.event.ActionEvent evt)
java英文自我介绍（优秀范文六篇）
java英文自我介绍（优秀范文六篇）本站小编为你整理了多篇相关的《java英文自我介绍(优秀范文六篇)》，但愿对你工作学习有帮助，当然你在本站还可以找到更多《java英文自我介绍(优秀范文六篇)》。
第一篇：java工程师英文自我介绍Good morning. It's a pleasure for me present myself. My name is xx, and I am a candidate for the position of java software engineerI am certain that my qualification and experience is at par with the job requirement. Hereby i am providing you with a brief overview of my skill set and achievments.I have completed my graduation in computer science from PQR college of sciences. I hold a diploma in software testing techniques. I have an extensive work experience in the relevant field for 5 years. I have worked as a supervisor of a 5 member team for software testing. The responsibilities i carried out included analysing and testing software using JavaScipt and PHP languages. I have also looked after the technical testing department of the organization and solved whatever problems the software programs face while they were commercially run.I am confident of my interpersonal skills and have attended various international clients in the organization. I am fluent with English, Spanish and German. I recognise the importance of team work in an organisational success and actively seek methodical way to solutions. I am interseted to be associated with your organization at a responsible position. I hope that through my work experience I will be a new member of your JAVA programming team. More information about my programming experiences and abilities is detailed in my CV enclosed with thisletter第二篇：面试英文自我介绍范文I am very happy to introduce myself here.I was born in Liaoning Province.I graduated from Nankai University and majored in International Trade.I like music and reaingbooks,especially economical books.It is my honor to apply this job.I hope I can realise my dream in our company.Please give me a chance.Thank you very much.It is my great pleasure to introduce myself.i was born in LIAONING.My major isinternational trade.I was graduated in Nankai University.My hobby lies in the music and reading, especially like economics.I am glad that i can take part in this interview and i am sincerely hope that i can join this company to realize my dream.please give my a chance.Thank you.第三篇：java工程师英文自我介绍My name is wang hai yan. I am a student who is about to graduate from changchun university in July 2013. In this career, I sincerely recommend myself with a sincere heart and dedication to my career.I love this profession and I love it. During the period of school, I have mastered solid professional basic knowledge, learning thebasic knowledge of mathematics and computer, cultivate logical thinking ability and the earnest careful learning attitude, and completed the learning task. Because I am very interested in the Java programming language, I use after school time took part in the soft international software engineer training workshops, professional for the Java programming aspects of learning. Mainly studied the Java core technology, the related operation and use of oracle database, JDBC connection database, web programming, SSH framework has done several projects, the basis of Java development ability; In addition, I passed the national English test band four and had good listening and writing skills.I am scrupulous in my studies, and I also have a hard time in my work. I was a competitive person in the class, successfully masterminded the series of TuanRi activities in the class, get the consistent high praise, I organized TuanRi activity was chosen as one of the top ten TuanRi activities, I also was rated "outstanding cadres", this in order to improve my communication skills and cultivate my team spirit of cooperation laid a good foundation.In October 2012 to February 2013, during this period, I worked in Vince hisoft technology co., LTD. VMware test group internship, my main work is responsible for set up according to the requirements of the test system, German and German platform according to the case of VM products do some tests.College graduation is both an end and a starting point. Now, with full confidence, I have embarked on the new steps of my life, and I sincerely hope that there will be a stage where I can reach my potential and show value. I hope your organization gives me a chance, I will do my best, with all my enthusiasm and hard work, dedication my youth and talent!第四篇：java面试英文自我介绍My name is XXX, this year is 21 years old, graduated from XX PLA information engineering university computer science and technology professionals, in the four years of college life, I have grasped the development and application of technology, but also in the development of the network have the profound understanding.So to lay a solid foundation of professional knowledge.In the thoughts and behavior, thought progress, positive enterprising, has the self-confidence, have very strong work sense of responsibility and the dedication to work, work steadfast, bears hardships and stands hard work, have a high comprehensive quality training.During the period of school has many social practice experience, has participated in college online virtual laboratory development needs analysis, the university period as many times more course lesson representative.Professional knowledge, proficient in C/C programming language, capable of using the language for software development; Master Visual C 6.0 programming software, has the rich based on Windows platform write software experience.Understand TCP/IP protocol, familiar with the basic principle of database; Have relatively rich web design and development experience, was instrumental in construction and maintenance institute's web site.Actively participate in a number of research projects.Has a strong professional ability.Have a solid Core Java foundation, good programming style; Familiar with Tomcat, Jboss server and so on, familiar based onLinux and Unix environment of software development.Although the actual work experience is not very full, but point four years developed my full confidence and professional dedication and solid base of the discipline knowledge and strong professional skills, four years of military school life, I strict demands on themselves, and consciously, observance of discipline and punctuality.I am honest and have the sense of responsibility, has the independent enterprising character, is industrious hands, good at one's brains, adapt to the new environment ability.Can be in the shortest time to finish from students to professional staff transformation, try your best into the new work and life.After four years of study, training I become a moral right, has a strong will and a lofty ideal, has the enterprising spirit and team cooperation spirit of good students.Believe what I have knowledge and competence can fit for any hard work.If I am lucky enough to become a member of your company, I will put all the youth and enthusiasm bend force into work, obtain due scores, for the development of the company to contribute their strength.第五篇：英语自我介绍java面试Leaders, my name is XXX, the remaining more than gold, gold.My hometown is in Gushi County of Henan Province, the parents are alive are all in good health, I have a sister in Wuhan.I am 07 years university graduate, majoring in computer software andJavar technology.Remember that before graduation to find work in Shanghai,then in Shanghai Wanda company internship, six months after the positive to health services, programmers working in medical and health projects.It is a total of about a year and a half, quit.The reason is probably that the work atmosphere made me feel not what plus was also feeling good jump to a Japanese company to work, just at that time the company in CMMI3, do the project in strict accordance with the CMMI process to go, what documents, Coding, I have to participate in the test.That time is really learned a lot of things on the project, may be just what the financial crisis, the company originally promised wages did not materialize and left.Go to the Shanghai XX Information Company, from the beginning of the project the main force to the development of the project leader, my biggest harvest in the agricultural letter nearly three years of work is, let me face to face communication better needs freedom in the project with the client side, late in the project to provide training and project by customer feedback and project to know.May be I can't adapt to the changes of company, then put forward to leave away.第六篇：java工程师英文自我介绍Good morning, ladies and gentlemen! It is really my honor to have this opportunity for an interview. I hope I can make a good performance today. I'm confident that I can succeed. Now I will introduce myself briefly. I am 26 years old, born in Shandong province. I graduated from Qingdao University. My major is electronics. And I got my bachelor degree after my graduation in the year of 2003. I spent most of my time on study, and I’ve passed CET-6 during my university. And I’ve acquired basicknowledge of my major. It is my long cherished dream to be an engineer and I am eager to get an opportunity to fully play my ability.In July 2003, I began working for a small private company as a technical support engineer in Qingdao city. Because there was no more chance for me to give full play to my talent, so I decided to change my job. And in August 2004, I left for Beijing and worked for a foreign enterprise as an automation software test engineer. Because I want to change my working environment, I'd like to find a job which is more challenging. Moreover，Motorola is a global company, so I feel I can gain a lot from working in this kind of company. That is the reason why I come here to compete for this position. I think I'm a good team player and a person of great honesty to others. Also，I am able to work under great pressure. I am confident that I am qualified for the post of engineer in your company.That’s all. Thank you for giving me the chance.。
Java常用命令汇总
Java常⽤命令汇总这篇⽂章就主要向⼤家展⽰了Java编程中常⽤的命令，下⾯看下具体内容。
1、javac将⽂件编译成.class⽂件⽤法: javac <options> <source files>其中, 可能的选项包括:-g ⽣成所有调试信息-g:none 不⽣成任何调试信息-g:{lines,vars,source} 只⽣成某些调试信息-nowarn 不⽣成任何警告-verbose 输出有关编译器正在执⾏的操作的消息-deprecation 输出使⽤已过时的 API 的源位置-classpath <路径> 指定查找⽤户类⽂件和注释处理程序的位置-cp <路径> 指定查找⽤户类⽂件和注释处理程序的位置-sourcepath <路径> 指定查找输⼊源⽂件的位置-bootclasspath <路径> 覆盖引导类⽂件的位置-extdirs <⽬录> 覆盖所安装扩展的位置-endorseddirs <⽬录> 覆盖签名的标准路径的位置-proc:{none,only} 控制是否执⾏注释处理和/或编译。
-processor <class1>[,<class2>,<class3>...] 要运⾏的注释处理程序的名称; 绕过默认的搜索进程-processorpath <路径> 指定查找注释处理程序的位置-d <⽬录> 指定放置⽣成的类⽂件的位置-s <⽬录> 指定放置⽣成的源⽂件的位置-implicit:{none,class} 指定是否为隐式引⽤⽂件⽣成类⽂件-encoding <编码> 指定源⽂件使⽤的字符编码-source <发⾏版> 提供与指定发⾏版的源兼容性-target <发⾏版> ⽣成特定 VM 版本的类⽂件-version 版本信息-help 输出标准选项的提要-A关键字[=值] 传递给注释处理程序的选项-X 输出⾮标准选项的提要-J<标记> 直接将 <标记> 传递给运⾏时系统-Werror 出现警告时终⽌编译@<⽂件名> 从⽂件读取选项和⽂件名2、java执⾏ .class⽂件，若类中没有main函数，则不能执⾏。
JAVA控制台命令详解
JAVA控制台命令详解(一)命令概览javac：Java编译器，将Java源代码换成字节代java：Java解释器，直接从类文件执行Java应用程序代码appletviewer(小程序浏览器)：一种执行HTML文件上的Java小程序类的Java浏览器javadoc：根据Java源代码及其说明语句生成的HTML文档jdb：Java调试器，可以逐行地执行程序、设置断点和检查变量javah：产生可以调用Java过程的C过程，或建立能被Java程序调用的C过程的头文件Javap：Java反汇编器，显示编译类文件中的可访问功能和数据，同时显示字节代码含义jar：多用途的存档及压缩工具，是个java应用程序，可将多个文件合并为单个JAR归档文件。
htmlConverter——命令转换工具。
native2ascii——将含有不是Unicode或Latinl字符的的文件转换为Unicode编码字符的文件。
serialver——返回serialverUID。
语法：serialver[show]命令选项show是用来显示一个简单的界面。
输入完整的类名按Enter键或"显示"按钮，可显示serialverUID。
（二）命令详细介绍补充详细：1.javac.exe用法：javac<选项><源文件>可能的选项包括：-g生成所有调试信息-g:none生成无调试信息-g:{lines,vars,source}生成只有部分调试信息-O优化；可能妨碍调试或者增大类文件-nowarn生成无警告-verbose输出关于编译器正在做的信息-deprecation输出使用了不鼓励使用的API的源程序位置-classpath<路径>指定用户类文件的位置-sourcepath<路径>指定输入源文件的位置-bootclasspath<路径>覆盖自举类文件的位置-extdirs<目录(多个)>覆盖安装的扩展类的位置-d<目录>指定输出类文件的位置-encoding<编码>指定源文件中所用的字符集编码-target<版本>生成指定虚拟机版本的类文件-help Print a synopsis of standard options2.Java.exeJava在运行已编译完成的类时，是通过java虚拟机来装载和执行的，java虚拟机通过操作系统命令JAVA_HOME\bin\java–option来启动，-option为虚拟机参数，JAVA_HOME为JDK安装路径，通过这些参数可对虚拟机的运行状态进行调整，掌握参数的含义可对虚拟机的运行模式有更深入理解。
jct_overview
Java Card Language Subset
Supported Java feature
Small primitive data types: boolean, byte, short OneOne-dimensional array Java packages, classes, interfaces, and exceptions Java object-oriented objectfeature: inheritance, virtual methods, overloading and dynamic object creation, access scope, and binding rules The int keyword and 32-bit 32integer data type support are optional
Java Card Converter
The converter processed one class at a time, the conversion unit of it is a package The converter takes two input : class files and export files
interpreter
Class files CAP file
CAP File and Export File
The converter loads and preprocess the class files and outputs a CAP file A CAP file contains an executable binary representation of the class in Java package A CAP file is a JAR file that contains a set of components. Each component describes an aspect of CAP file content, such as class information, executable bytecode, linking information, verification information and so forth The CAP file format is optimized for small small footprint by compact data structure and limited indirection.
java命令大全
java命令大全（实用版）目录1.Java 命令概述2.Java 基本命令3.Java 高级命令正文【Java 命令概述】Java 命令是 Java 编程语言中使用的命令，可以帮助开发者管理和运行 Java 程序。
Java 命令包括基本命令和高级命令，这些命令可以使开发者更加高效地完成各种任务。
本文将为您详细介绍 Java 命令大全，帮助您更好地理解和使用这些命令。
【Java 基本命令】1.javac：Java 编译器，用于将 Java 源代码编译成字节码文件。
用法：javac 文件名.java2.java：Java 运行时环境，用于运行字节码文件。
用法：java 文件名3.jps：Java 进程管理器，用于查看和控制 Java 进程。
用法：jps [选项]4.jstat：Java 统计信息命令，用于查看 Java 虚拟机和应用程序的统计信息。
用法：jstat [选项]5.jconsole：Java 监控和管理控制台，用于监控 Java 虚拟机和应用程序的性能。
用法：jconsole [选项]【Java 高级命令】1.jvisualvm：Java 可视化虚拟机，用于监控和分析 Java 应用程序的性能。
用法：jvisualvm [选项]2.jdb：Java 调试器，用于调试 Java 应用程序。
用法：jdb [选项]3.jre：Java 运行时环境，用于运行 Java 程序。
用法：jre [选项]4.jrmi：Java 远程方法调用，用于实现 Java 对象间的远程方法调用。
用法：jrmi [选项]5.jsr：Java 代码规范，用于检查 Java 代码是否符合规范。
用法：jsr [选项]通过以上介绍，您应该已经了解了 Java 命令大全中的基本命令和高级命令。
关于java前后端分离开发的文献
关于java前后端分离开发的文献（中英文实用版）Title: A Literature Review on Java Front-end and Back-end Separation DevelopmentAbstract: This paper aims to provide a comprehensive overview of the current state of Java front-end and back-end separation development.By examining various research articles, conference papers, and technical blogs, we identify the main techniques, tools, and frameworks used in this context, as well as the advantages and challenges associated with this approach.The paper also discusses the future trends and potential improvements in Java front-end and back-end separation development.1.IntroductionJava has long been a popular choice for developing enterprise-level applications due to its robustness, portability, and scalability.In recent years, the trend of front-end and back-end separation has gained significant momentum in the Java community.This paper presents a literature review on this topic, exploring the techniques, tools, and frameworks commonly used, as well as the benefits and drawbacks of this approach.1.1 BackgroundFront-end and back-end separation is a software architecture patternthat divides an application into two distinct components: the front-end (user interface) and the back-end (business logic and data storage).This separation allows for independent development, testing, and deployment of each component, leading to better maintainability, reusability, and scalability.1.2 ObjectiveThe objective of this literature review is to provide a concise summary of the existing research on Java front-end and back-end separation development.We aim to identify the most commonly used techniques, tools, and frameworks, as well as to highlight the advantages and challenges associated with this approach.2.Techniques, Tools, and FrameworksThis section presents an overview of the techniques, tools, and frameworks commonly used in Java front-end and back-end separation development.The selection of these technologies is based on the prevalence and popularity in the industry, as well as the significance in the literature.2.1 Front-end DevelopmentJavaScript is the primary language used for front-end development.Popular JavaScript frameworks and libraries include React, Angular, and Vue.js.These frameworks enable developers to create dynamic and interactive user interfaces.Additionally, CSS preprocessors(e.g., Sass, Less) and build tools (e.g., Webpack, Gulp) are commonly used to enhance the productivity and maintainability of front-end code.2.2 Back-end DevelopmentSpring Boot is the most widely used framework for Java back-end development.It simplifies the process of creating stand-alone, production-grade Spring-based applications.Other popular Java frameworks include Java EE, Hibernate, and Struts.For database management, developers commonly use SQL databases (e.g., MySQL, PostgreSQL) and NoSQL databases (e.g., MongoDB, Cassandra).2.3 API DevelopmentRESTful API is the preferred approach for communication between the front-end and back-end components.Spring RESTful is a popular framework for building RESTful web services in Java.Additionally, GraphQL is gaining traction as an alternative to RESTful APIs, as it allows clients to request exactly the data they need.3.Advantages and ChallengesFront-end and back-end separation in Java development offers several advantages, as well as some challenges.This section highlights the key benefits and drawbacks identified in the literature.3.1 Advantages- Better code organization and maintainability- Independent development, testing, and deployment of front-endand back-end components- Improved scalability and performance- Increased reusability of components- Easier collaboration between front-end and back-end developers3.2 Challenges- Increased complexity in tooling and build processes- Potential for increased network latency due to communication between front-end and back-end components- Difficulty in managing state and session data across separated components- Potential for increased security vulnerabilities, as attackers may target either the front-end or back-end component4.Future Trends and ImprovementsThe literature suggests several potential improvements and emerging trends in Java front-end and back-end separation development.These include:- Increased adoption of microservices architecture, which further enhances the separation between front-end and back-end components - Integration of containerization technologies (e.g., Docker) for easier deployment and scaling of applications- Use of server-side rendering (SSR) and static site generation (SSG) to improve performance and reduce the complexity of front-endapplications- Continuous integration and deployment (CI/CD) practices to streamline the development and deployment process5.ConclusionJava front-end and。
java文档注释规范（一）
java⽂档注释规范（⼀）https:///huangsiqian/article/details/82725214Javadoc⼯具将从四种不同类型的“源”⽂件⽣成输出⽂档：Java语⾔类的源⽂件（.java），包注释⽂件，概述注释⽂件和其他未处理的⽂件。
包注释⽂件（Package Comment File）每个包都有⾃⼰的⽂档注释。
有两种⽅式来创建包注释⽂件：package-info.java - 可以包含包的声明，包注解（anotation），包注释和Javadoc 标签（tag）。
包注释放在包声明之前。
这是JDK 5.0新引⼊的特性。
如下。
File: java/applet/package-info.java 注意：⽂档注释块内部⾏⾸的*号是可选的/*** Provides the classes necessary to create an applet and the classes an applet uses* to communicate with its applet context.* <p>* The applet framework involves two entities:* the applet and the applet context. An applet is an embeddable window (see the* {@link java.awt.Panel} class) with a few extra methods that the applet context* can use to initialize, start, and stop the applet.** @since 1.0* @see java.awt*/package ng.applet;package.html - 只能包含包注释和Javadoc标签，不能包含包注解。
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西安电子科技大学软件学院《Java技术》
刘惠
RoadMap
Java 发展历程 Java 语言的特性 Java与C++的比较 Java的发展方向和应用领域 Java平台技术 Java 2 SDK 建立开发环境 JDK开发工具的使用
西安电子科技大学软件学院《Java技术》 刘惠
Java与C++的比较（1）
二者相同之处
变量声明 参数传递 操作符 流程控制
二者不同之处
Java没有全局变量，而是用public , static的类变量来代替全局变量。 Java取消goto语句，而是通过异常处理语句try、catch、final等来代 替C/C++中用goto语句来处理遇到错误时跳转的情况，使得程序可 读且更结构化。
西安电子科技大学软件学院《Java技术》 刘惠
按执行方式分类
编译执行语言
编译执行是在编写完程序以后，通过特定的工具 软件将源程序转换成可执行程序，直接交由操作 系统执行，即程序作为一个整体执行。例如C， C++语言。
解释执行语言
解释执行是程序读入一句执行一句，而不需要整 体编译链接。例如Java，Basic语言。
西安电子科技大学软件学院《Java技术》 刘惠
按思维模式分类
面向过程的程序设计语言
面向过程的程序设计语言注重数据结构和算法，研究采用 什么样的数据结构描述问题，采用什么样的算法来高效解 决问题。例如Basic,Fortran,Pascal,C 等。
面向对象的程序设计语言
面向对象以一种更接近人类一般思维的方式去看待世界， 将世界上的任何一个个体看作一个对象。提高程序的重用 性。例如Java，Smalltalk，C++等。
西安电子科技大学软件学院《Java技术》 刘惠
Java认证器包括四个阶段的操作：类文件认证、类型系统认证、字节码认 证和运行时类型与访问检查。此外，认证器在检查期间还能识别算法 操作的上溢和下溢等其他可能发生在运行期间的程序错误。
Java的效率和（Just-In-Time）JIT及时编译技术：JIT编译器
分布式
分布式包括数据分布和计算分布。
解释执行
西安电子科技大学软件学院《Java技术》 刘惠
Java语言的特性（2）
健壮性
Java提供自动垃圾回收机制进行内存管理 Java提供面向对象的异常处理机制 Java进行严格的类型检查。
平台无关性
平台无关性是指用Java编写的程序不用修改就可以在不同的软硬件平台上 运行。 与平台无关的特性使得Java程序可以方便的移植到网络中不同机器。 Java源程序被编译成一种高层次的与机器无关的字节码格式。
西安电子科技大学软件学院《Java技术》 刘惠
按发展例程分类
５０年代中期，FORTRAN语言是第一个划时代的程序设计语言。引 入变量，数组，控制结构。 ５０年代后期，Algol语言引入块结构。这是程序设计语言中第一次尝 试为数据提供保护和封装。 ６０年代，Simula 67语言被公认为面向对象语言的鼻祖。引入类，继 承。 ７０年代，出现了数据抽象。支持它的最重要的语言是美国国防部开 发的Ada语言，用于嵌入式实时系统 ７０年代和８０年代，出现了SmallTalk语言，纯面向对象语言。 自从1986年，面向对象技术逐渐走出实验室，开始实际应用。ObjectC, Eiffel等都是后续的较有广泛影响的语言。他们是全新的面向对象 语言。 80年代早期，贝尔实验室开发了C++,混合型语言。 90年代，Java诞生。
西安电子科技大学软件学院《Java技术》 刘惠
Java解释器(1)
解释器
运行JVM字节码的工作是由Java解释器来完成的。解释执 行过程分三部分进行：代码的装入、代码的校验和代码的 执行。
代码装入
装入代码的工作由“类装载器”完成。它从磁盘上或者网络上取 字节代码，负责装入运行一个程序所需要的所有代码，包括程序 代码中的类所继承的类和被其调用的类。当装入了运行程序需要 的所有类后，解释器便可确定整个可执行程序的内存布局，解释 器为符号引用统特定的地址空间建立对应关系及查询表。通过这 一阶段确定代码的内存布局，Java很好的解决了由于超类改变而使 子类崩溃的问题，同时也防止了代码对地址的非法访问。
基于CORBA的Java分布式应用 Java企业级解决方案——J2EE
西安电子科技大学软件学院《Java技术》 刘惠
RoadMap
Java 发展历程 Java 语言的特性 Java与C++的比较 Java的发展方向和应用领域 Java平台技术 Java 2 SDK 建立开发环境 JDK开发工具的使用
在程序开始执行前把所有字节码翻译成本地机器码，然后再将翻译后 的机器码放在CPU上运行。
西安电子科技大学软件学院《Java技术》
刘惠
Java虚拟机
什么是java虚拟机：
Java虚拟机是一个想象中的机器,在实际的计算机上通过 软件模拟来实现。Java虚拟机有自己想象中的硬件,如处 理器、堆栈、寄存器等,还具有相应的指令系统。
西安电子科技大学软件学院《Java技术》 刘惠
RoadMap
程序设计语言简介 Java 发展历程 Java 语言的特性 Java与C++的比较 Java的发展方向和应用领域 Java平台技术 Java 2 SDK 建立开发环境 JDK开发工具的使用
西安电子科技大学软件学院《Java技术》 刘惠
Java 发展历程
Java来自于Sun公司一个叫Green的项目，该项目原先的目的是为家用 消费电子产品开发一个分布式代码系统，这样用户就可以把e-mail发 给电冰箱，电视机等家用电器，对它们进行控制。（即原先是为了家 用电器进行集成控制而设计的一种语言。）
Java的前身叫Oak，是一种用于网络的精巧而安全的语言，但最后没有 得到好的发展。
Java Overview
西安电子科技大学软件学院 刘 惠
西安电子科技大学软件学院《Java技术》刘惠
RoadMap
程序设计语言简介 Java 发展历程 Java 语言的特性 Java与C++的比较 Java的发展方向和应用领域 Java平台技术 Java 2 SDK 建立开发环境 JDK开发工具的使用
西安电子科技大学软件学院《Java技术》 刘惠
Java平台技术（1）
Java虚拟机： 从底层看，Java虚拟机就是以Java字节码为指令组的软 CPU。 字节码： 字节码是Java虚拟机的指令组（很象CPU上的微码）。 即用即装入： 一个.class文件可以引用许多其它.class文件（在Java语言中， 通过import, implement或extends语句实现），当运行的类 需要其他类时，Java虚拟机即从网络或本地文件系统装 入.class文件。
西安电子科技大学软件学院《Java技术》
刘惠
Java语言的特性（3）
安全性
用于网络，分布环境下的Java必须要防止病毒的入侵，因此，Java 不支持指针，一切对内存的访问都必须通过对象的实例变量莱实 现，这样就防止了黑客用“特洛伊”木马等欺骗手段访问对象的 私有成员，同时也避免了指针操作中容易产生的错误。 多线程是操作系统的一种新概念，是比传统进程更小的可并发执 行的单位。C/C++采用单线程体系结构，而Java对多线程提供语言 级别的支持，这是其他语言无法比拟的。 Java的动态性是其面向对象设计方法的扩展。它允许程序动态的装 入运行过程中所需要的类，这是C++语言进行面向对象程序设计时 无法实现的。
西安电子科技大学软件学院《Java技术》 刘惠
Java语言的特性（1）
简单性
Java风格类似于C++，但它摒弃了C++中容易引起程序错误的地方，如 指针和内存管理。同时提供了丰富的类库供开发者使用。
面向对象
Java语言的设计是完全面向对象，它不支持像C那样的面向过程的程序 设计技术。但从面向对象的特性来看，Java类似于SmallTalk，但从适 用于分布式计算环境的特性远远超越了SmallTalk。
Java虚拟机工作原理：
C/C++编译器生成的代码是针对于某一特定的硬件平台运行而产 生的。即在编译过程中，编译程序通过查表将所有对符号的引用 转换为特定的内存偏移量。 Java编译程序不把变量和方法的引用编译为数值引用，也不确定 程序执行过程中的内存布局，而是将这些符号引用信息保留在字 节码中，由解释器在运行过程中创立内存布局，然后通过查表来 确定一个方法所在的地址。
西安电子科技大学软件学院《Java技术》
刘惠
Java与C++的比较（3）
类型转换：在C/C++中，可以通过指针进行任意的类型转换，常常 带来了不安全性，而Java中，运行时系统对对象的处理要进行类型 检查，防止出现不安全的转换。 头文件：C/C++中用头文件来声明类的原型以及全局变量、库函数 等，Java中不支持头文件，类成员的类型和访问权限都封装在一个 类中。 结构和联合：C,C++中的结构和联合所有成员都是公有的，带来了 安全性的问题，Java中没有结构和联合，所有内容都封装在类中。 Java不支持宏。常量定义用关键字final。