基于jsp校园二手交易系统的设计与实现外文翻译

基于jsp校园二手交易系统的设计与实现外文翻译内容摘要：

ge as powerful as Java is easy. You always have to distinguish between how easy it is to write toy programs and how hard it is to do serious work. Also, consider that only four chapters in this book discuss the Java language. will bee a universal programming language for all platforms. This is possible, in theory, and it is certainly the case that every vendor but Microsoft seems to want this to happen. However, many applications, already working perfectly well on desktops, would not work well on other devices or inside a browser. Also, these applications have been written to take advantage of the speed of the processor and the native user interface library and have been ported to all the important platforms anyway. Among these kinds of applications are word processors, photo editors, and web browsers. They are typically written in C or C++, and we see no benefit to the end user in rewriting them in Java. is just another programming language. Java is a nice programming language。 most programmers prefer it over C, C++, or C. But there have been hundreds of nice programming languages that never gained wide spread popularity, whereas languages with obvious flaws, such as C++ and Visual Basic, have been wildly successful. Why? The success of a programming language is determined far more by the utility of the support system surrounding it than by the elegance of its syntax. Are there useful, convenient, and standard libraries for the features that you need to implement? Are there tool vendors that build great programming and debugging environments? Does the language and the toolset integrate with the rest of the puting infrastructure? Java is successful because its class libraries let you easily do things that were hard before, such as working and multithreading. The fact that Java reduces pointer errors is a bonus and so programmers seem to be more productive with Java, but these factors are not the source of its success. that C is available, Java is obsolete. C took many good ideas from Java, such as a clean programming language, a virtual machine, and garbage collection. But for whatever reasons, C also left some good stuff behind, in particular security and platform independence. If you are tied to Windows, C makes a lot of sense. But judging by the job ads, Java is still the language of choice for a majority of developers. is proprietary, and it should therefore be avoided. Sun Microsystems licenses Java to distributors and end users. Although Sun has ulti mate control over Java through the “Java Community Process,” they have involved many other panies in the development of language revisions and the design of new libraries. Source code for the virtual machine and the libraries has always been freely available, but only for inspection, not for modification and redistribution. Up to this point, Java has been “closed source, but playing nice.” is interpreted, so it is too slow for serious applications. In the early days of Java, the language was interpreted. Nowadays, except on “micro” platforms such as cell phones, the Java virtual machine uses a justintime piler. The“ hot spots” of your code will run just as fast in Java as they would in C++, and in some cases, they will run faster. Java does have some additional overhead over C++. Virtual machine startup time is slow, and Java GUIs are slower than their native co。