Java SE 8新特性速览：Lambda表达式与并发编程革新

需积分: 10 70 浏览量更新于2024-07-20 1 收藏 7.7MB PDF 举报

"Java SE 8 for the Really Impatient" 是一本由知名Java专家Cay S. Horstmann编写的书籍，旨在为经验丰富的Java程序员快速介绍Java 8的重要新特性，以及一些未受到足够关注的Java 7特性。书中涵盖了Lambda表达式、并发编程更新、日期/时间库（JSR 310）、类型注解、Java/JavaScript集成（Project Nashorn）、JavaFX API的应用以及HotSpot JVM垃圾收集的优化。 Java 8是Java语言的一次重大更新，主要知识点包括： 1. **Lambda表达式**：Lambda表达式引入了函数式编程的概念，允许开发者定义可传递的匿名函数，即所谓的“计算片段”。这使得处理Java集合时更加灵活，例如可以方便地应用filter、map和reduce等操作。 2. **并发编程的更新**：利用Lambda表达式改进了并发编程，如在并行流中使用filter、map和reduce等函数，以及对Java的Fork-Join框架的优化，提升了多线程程序的效率。 3. **JSR 310：日期/时间库**：Java 8引入了全新的日期、时间和日历库，取代了原有的不完善的API，提供了更强大且易用的时间处理功能。 4. **类型注解**：Java 8支持在类型上使用注解，这有助于实现可插拔的类型检查器，从而强化Java内置的类型系统，提升代码的健壮性。 5. **Project Nashorn：Java/JavaScript集成**：通过Project Nashorn，Java 8允许直接在Java应用程序中执行JavaScript代码，实现了两者之间的无缝交互。 6. **JavaFX API**：Java 8将JavaFX作为创建媒体丰富、高度交互的客户端应用程序的官方方式，提供了一套用于图形用户界面设计的强大工具。 7. **HotSpot JVM调优**：简化了HotSpot虚拟机的垃圾收集调优过程，帮助开发者更好地管理和优化内存使用。这本书面向想要编写更强大、高效、安全的Java代码的程序员，是学习和掌握Java 8新特性的宝贵资源。通过Cay S. Horstmann的实用洞察和示例代码，读者能够迅速掌握这些新特性并将其应用于实际开发中。

ptg12441863

Cay S. Horstmann is the author of Scala for the Impatient (Addison-Wesley, 2012),

is principal author of Core Java

™

, Volumes I and II, Ninth Edition (Prentice Hall,

2013), and has written a dozen other books for professional programmers and

computer science students. He is a professor of computer science at San Jose State

University and is a Java Champion.

About the Author

www.it-ebooks.info

ptg12441863

Arrays.sort(strings, new LengthComparator());

The sort method keeps calling the compare method, rearranging the elements if

they are out of order, until the array is sorted. You give the sort method a snippet

of code needed to compare elements, and that code is integrated into the rest of

the sorting logic, which you’d probably not care to reimplement.

NOTE: The call Integer.compare(x, y) returns zero if x and y are equal, a

negative number if x < y, and a positive number if x > y. This static method

has been added to Java 7 (see Chapter 9). Note that you shouldn’t compute

x - y to compare x and y since that computation can overﬂow for large

operands of opposite sign.

As another example for deferred execution, consider a button callback. You put

the callback action into a method of a class implementing the listener interface,

construct an instance, and register the instance with the button. That happens so

often that many programmers use the “anonymous instance of anonymous class”

syntax:

button.setOnAction(new EventHandler<ActionEvent>() {

public void handle(ActionEvent event) {

System.out.println("Thanks for clicking!");

}

});

What matters is the code inside the handle method. That code is executed

whenever the button is clicked.

NOTE: Since Java 8 positions JavaFX as the successor to the Swing GUI

toolkit, I use JavaFX in these examples. (See Chapter 4 for more information

on JavaFX.) Of course, the details don’t matter. In every user interface toolkit,

be it Swing, JavaFX, or Android, you give a button some code that you want

to run when the button is clicked.

In all three examples, you saw the same approach. A block of code was passed

to someone—a thread pool, a sort method, or a button. The code was called at

some later time.

Up to now, giving someone a block of code hasn’t been easy in Java. You couldn’t

just pass code blocks around. Java is an object-oriented language, so you had to

construct an object belonging to a class that has a method with the desired code.

In other languages, it is possible to work with blocks of code directly. The Java

designers have resisted adding this feature for a long time. After all, a great

1.1 Why Lambdas?

www.it-ebooks.info

剩余237页未读，继续阅读

gshlsh

粉丝: 0
资源: 2

Java SE 8新特性速览：Lambda表达式与并发编程革新

Java SE 8 for the Really Impatient epub

Java SE 8 for the Really Impatient 写给大忙人看的Java SE 8 源码

java近几年英文文献,Java演进英文文献和中文翻译

java参考文献2020

core java for the impatient pdf

帮我找一下可以写再javaweb毕设里的英文参考文献

c++ impatient

Comment Chéri traite sa femme Edme, dans le roman Chéri 的Colette

12306抢票脚本 - Bypass

单片机与蓝牙模块的无线通信项目实战.md

最新资源