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1、 毕业设计说明书英文文献及中文翻译 班 级： 学号： 软件学院姓 名： 软件工程学 院： 专 业： 指导教师： 2014 年 6 月An Introduction to JavaThe first release of Java in 1996 generated an incredible amount of excitement, not just in the computer press, but in mainstream media such as The New York Times, The Washington Post, and Business Week. Java ha
2、s the distinction of being the first and only programming language that had a ten-minute story on National Public Radio. A $100,000,000 venture capital fund was set up solely for products produced by use of a specific computer language. It is rather amusing to revisit those heady times, and we give
3、you a brief history of Java in this chapter. In the first edition of this book, we had this to write about Java: “As a computer language, Javas hype is overdone: Java is certainly a good program-ming language. There is no doubt that it is one of the better languages available to serious programmers.
4、 We think it could potentially have been a great programming language, but it is probably too late for that. Once a language is out in the field, the ugly reality of compatibility with existing code sets in.” Our editor got a lot of flack for this paragraph from someone very high up at Sun Micro- sy
5、stems who shall remain unnamed. But, in hindsight, our prognosis seems accurate. Java has a lot of nice language featureswe examine them in detail later in this chapter. It has its share of warts, and newer additions to the language are not as elegant as the original ones because of the ugly reality
6、 of compatibility. But, as we already said in the first edition, Java was never just a language. There are lots of programming languages out there, and few of them make much of a splash. Java is a whole platform, with a huge library, containing lots of reusable code, and an execution environment tha
7、t provides services such as security, portability across operating sys-tems, and automatic garbage collection. As a programmer, you will want a language with a pleasant syntax and comprehensible semantics (i.e., not C+). Java fits the bill, as do dozens of other fine languages. Some languages give y
8、ou portability, garbage collection, and the like, but they dont have much of a library, forcing you to roll your own if you want fancy graphics or network- ing or database access. Well, Java has everythinga good language, a high-quality exe- cution environment, and a vast library. That combination i
9、s what makes Java an irresistible proposition to so many programmers.Simple We wanted to build a system that could be programmed easily without a lot of eso- teric training and which leveraged todays standard practice. So even though we found that C+ was unsuitable, we designed Java as closely to C+
10、 as possible in order to make the system more comprehensible. Java omits many rarely used, poorly understood, confusing features of C+ that, in our experience, bring more grief than benefit. The syntax for Java is, indeed, a cleaned-up version of the syntax for C+. There is no need for header files,
11、 pointer arithmetic (or even a pointer syntax), structures, unions, operator overloading, virtual base classes, and so on. (See the C+ notes interspersed throughout the text for more on the differences between Java and C+.) The designers did not, however, attempt to fix all of the clumsy features of
12、 C+. For example, the syn- tax of the switch statement is unchanged in Java. If you know C+, you will find the tran- sition to the Java syntax easy. If you are used to a visual programming environment (such as Visual Basic), you will not find Java simple. There is much strange syntax (though it does
13、 not take long to get the hang of it). More important, you must do a lot more programming in Java. The beauty of Visual Basic is that its visual design environment almost automatically pro- vides a lot of the infrastructure for an application. The equivalent functionality must be programmed manually, usually with a fair bit of code, in Java. There are, however, third-party development environments that provide “drag-and-drop”-style program development. Another aspect of being simple is being small. One of the goals of Java is to enable th
