`
standalone
  • 浏览: 614291 次
  • 性别: Icon_minigender_1
  • 来自: 上海
社区版块
存档分类
最新评论

Multithreading in Java (3)

    博客分类:
  • java
阅读更多

 

Multithreading in Java - The Thread Classes and the Runnable Interface


(Page 3 of 10 )

You construct threads by using the Thread class and the Runnable interface. This means that your class must extend the Thread class or implement the Runnable interface. The Thread class defines the methods you use to manage threads. Table 10-1 contains the commonly used methods of the Thread class. You’ll see how these are used throughout the examples in this chapter.

 

 

Method

 

Description

 

getName()

 

Returns the name of the thread.

 

getPriority()

 

Returns the priority of the thread.

 

isAlive()

 

Determines whether the thread is running.

 

join()

 

Pauses until the thread terminates.

 

run()

 

The entry point into the thread.

 

sleep()

 

Suspends a thread. This method enables you to specify the period

 

 

the thread is suspended.

 

start()

 

Starts the thread.

 

Table 10-1   Commonly Used Methods Defined in the Thread Class

The Main Thread Every Java program has one thread, even if you don’t create any threads. This thread is called the main thread because it is the thread that executes when you start your program. The main thread spawns threads that you create. These are called child threads. The main thread is always the last thread to finish executing because typically the main thread needs to release a resource used by the program such as network connections.

 

Programmers can control the main thread by first creating a Thread object and then using method members of the Thread object to control the main thread. You create a Thread object by calling the currentThread() method. The currentThread() method returns a reference to the thread. You then use this reference to control the main thread just like you control any thread, which you’ll learn how to do in this chapter.

Let’s create a reference to the main thread and then change the name of the thread from main to Demo Thread. The following program shows how this is done. Here’s what is displayed on the screen when the program runs:

Current thread: Thread[main, 5,main]
Renamed Thread: Thread[Demo Thread, 5,main]
class Demo {
  
public static void main (String args[] ) {
     
Thread t = Thread.currentThread();
     
System.out.println("Current thread: " + t);
     
t.setName("Demo Thread");
     
System.out.println("Renamed Thread: " + t);
  
}
}

As you previously learned in this chapter, a thread is automatically created when you execute a program. The objective of this example is to declare a reference to a thread and then assign that reference a reference to the main thread. This is done in the first statement of the main() method.

We declare the reference by specifying the name of the class and the name for the reference, which is done in the following line of code:

Thread t

We acquire a reference to the main thread by calling the currentThread() method member of the Thread class using the following method call:

Thread.currentThread()

The reference returned by the currentThread() method is then assigned to the reference previously declared in the opening statement. We then display the thread on the screen:

Thread[main, 5,main]

Information within the square brackets tells us something about the thread. The first appearance of the word main is the name of the thread. The number 5 is the thread’s priority, which is normal priority. The priority ranges from 1 to 10, where 1 is the lowest priority and 10 is the highest. The last occurrence of the word main is the name of the group of threads with which the thread belongs. A thread group is a data structure used to control the state of a collection of threads. You don’t need to be concerned about a thread group because the Java run-time environment handles this.

The setName() method is then called to illustrate how you have control over the main thread of your program. The setName() method is a method member of the Thread class and is used to change the name of a thread. This example uses the setName() method to change the main thread’s name from main to Demo Thread. The thread is once again displayed on the screen to show that the name has been changed. Here’s what is displayed:

Renamed Thread: Thread[Demo Thread, 5,main]

分享到:
评论

相关推荐

    《Programming in Java Second Edition》高清完整英文PDF版

    Multithreading in Java Chapter 9. Input/Output, Serialization and Cloning Chapter 10. Generics, java.util and other API Chapter 11. Network Programming Chapter 12. Applets Chapter 13. Event Handling ...

    thinking in Java

    其中,"multithreading applications in Win32.pdf"可能是一个关于Windows平台下多线程应用的补充材料,可能出自另一本书或文章,但与《Thinking in Java》的主题相关。多线程是Java编程中的一个重要部分,它允许...

    1Z0-811 Exam Guide to Have a Cakewalk in Oracle Java SE Certific

    - **Concurrency:** Explore concurrency concepts and multithreading in Java. #### Conclusion The 1Z0-811 exam is a significant step towards achieving Oracle Java SE certification. By following a ...

    Multithreading-in-java

    Java多线程 多线程是Java的一项功能,它允许并发执行程序的两个或更多部分,以最大程度地利用CPU。 这种程序的每个部分都称为线程。 因此,线程是进程中的轻量级进程。 可以使用两种机制来创建线程: 扩展Thread类...

    Java: High-Performance Apps with Java 9

    3: MULTITHREADING AND REACTIVE PROGRAMMING 4: MICROSERVICES 5: MAKING USE OF NEW APIS TO IMPROVE YOUR CODE What You Will Learn Familiarize with modular development and its impact on performance Learn ...

    Java-Concurrency-Multithreading-in-Practice:Packt出版的《 Java Concurrency&Multithreading in Practice》

    实践中的Java并发和多线程 这是发行的的代码存储库。 它包含从头到尾完成视频课程所需的所有支持项目文件。 关于视频课程 多核处理器无处不在-从超级计算机到随身携带的移动设备。 这就是为什么现代开发人员必须知道...

    A Textbook of Java Programming

    It also discusses about exception handling, multithreading and java libraries. Further, it explains how to interact with client side applications like applets and handling events. The last section ...

    JAVA核心技术卷一卷二(中文)之part2分卷

    Chapter 3 Fundamental Programming Structures in Java(新增批注共44条) Chapter 4 Objects and Classes(新增批注共55条) Chapter 5 Inheritance(新增批注共42条) Chapter 6 Interfaces and Inner Classes...

    Java Performance and Scalability

    This book was written with one goal in mind: to provide Java programmers with the expertise needed to build efficient, scalable Java code. The author shares his experience in server-side performance ...

    Java.to.Python 高清完整epub版

    If Java is the heavy metal of computer programming, then Python is the jazz that opens doors of freedom in software development. Both Java and Python are object-oriented programming languages. Both ...

    Modern Multithreading

    Carver和Kuo-Chung Tai撰写,由John Wiley & Sons, Inc.出版,是一本深入探讨多线程编程的专著,尤其聚焦于Java和C++(包括Pthreads和Win32)语言环境下的多线程程序设计、测试与调试。本书不仅适合初学者作为入门...

    java面试题英文版及其答案

    s built-in support for multithreading through the Thread class and the Runnable interface. By creating and starting multiple threads, a Java application can perform several operations simultaneously, ...

    Java - A Beginner’s Guide - Sixth Edition - Herbert Schildt

    This chapter introduces multithreading concepts and techniques in Java, including thread creation, synchronization, and inter-thread communication. Multithreading is particularly useful for improving...

    Core Java. Volume I. Fundamentals, 8th Edition JAVA核心技术1基础知识

    3 FUNDAMENTAL PROGRAMMING STRUCTURES IN JAVA 4 OBJECTS AND CLASSES 5 INHERITANCE 6 INTERFACES AND INNER CLASSES 7 GRAPHICS PROGRAMMING 8 EVENT HANDLING 9 USER INTERFACE COMPONENTS WITH SWING 10 ...

    Thinking_in_Java_4th_Edition_CN

    9. **多线程(Multithreading)**:Java支持多线程编程,书中会讲解线程的创建、同步和通信,以及线程池的使用。 10. **输入/输出流(I/O Stream)**:介绍如何在Java中进行文件读写,网络通信以及其他类型的输入...

    Core.Java.B013WZRDNQ

    Core Java offers a total immersion approach for CC++ programmer wanting to learn java. The course will use JDK(Java Development Kit) and covers all the ...Chapter 13 Managing Input/Output Files in Java

    producer_consumer_using_multithreading_in_java:用Java实现的经典生产者消费者问题的多线程解决方案

    6. ** 示例代码 **:在`producer_consumer_using_multithreading_in_java-master`这个项目中,应该包含了一个完整的示例,演示了如何用Java实现生产者消费者模型。源代码可能包括一个`Producer`类和一个`Consumer`类...

    JAVA核心技术卷一卷二(中文)之part4分卷

    Chapter 3 Fundamental Programming Structures in Java(新增批注共44条) Chapter 4 Objects and Classes(新增批注共55条) Chapter 5 Inheritance(新增批注共42条) Chapter 6 Interfaces and Inner Classes...

Global site tag (gtag.js) - Google Analytics