ObjectInputStream in =newObjectInputStream(newFileInputStream(file)); SerializableSingleton b = (SerializableSingleton) in.readObject(); in.close(); assertEquals(a, b); } 3. Break Singleton with Reflection publicstaticvoidcheckReflection()throwsException { EagerSingleton a = EagerSingleton.getInstance...
packagecom.zcz.singleton;importjava.util.ArrayList;importjava.util.HashSet;importjava.util.List;importjava.util.Objects;importjava.util.Set;importjava.util.Vector;publicclassBuyTicket {publicstaticvoidmain(String[] args) {//用户人数intuserNumber = 10000;//保存用户线程Set<Thread> threadSet =newHash...
设计模式的征途—1.单例(Singleton)模式 单例模式属于创建型模式的一种,创建型模式是一类最常用的设计模式,在软件开发中应用非常广泛。创建型模式将对象的创建和使用分离,在使用对象时无需关心对象的创建细节,从而降低系统的耦合度,让设计方案更易于修改和扩展。每一个创建型模式都在视图回答3个问题:3W -> 创建什...
In the above code, the getInstance() method is not thread-safe. Multiple threads can access it at the same time. For the first few threads when the instance variable is not initialized, multiple threads can enter the if loop and create multiple instances. It will break our singleton implemen...
Singleton in C++ Singleton is a creational design pattern, whichensures that only one object of its kind exists and provides a single point of access to it for any other code. Singleton has almost the same pros and cons as global variables. Although they're super-handy, they break the modu...
importjava.util.Map; publicclassBreakHashMap { privatestaticfinalintTHREAD_COUNT = 500; privatestaticfinalBooleanLock startLock =newBooleanLock(); privatestaticfinalIntLock endLock =newIntLock(); publicstaticvoidmain(String[] args) { while(true) { ...
break; } } catch (Exception e) { e.printStackTrace(); } System.out.println(instanceOne.hashCode()); System.out.println(instanceTwo.hashCode()); } } 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17.
(Constructorconstructor:constructors){// This code will destroy the singleton patternconstructor.setAccessible(true);instanceTwo=(EagerInitializedSingleton)constructor.newInstance();break;}}catch(Exceptione){e.printStackTrace();}System.out.println(instanceOne.hashCode());System.out.println(instanceTwo....
Serialization is used to convert an object of byte stream and save in a file or send over a network. Suppose you serialize an object of a singleton class. Thenif you de-serialize that object it will createa new instance and hence break the singleton pattern. ...
本来看上面代码没有写多线程处理还有点失望,结果看下面的说明,它还提到了序列化,类加载的问题,不错不错,虽然我没有遇到,但能理解这些地方确实会break the singleton rule。不过没关系,我们先从简单的版本开始,然后询问chatgpt看能不能告诉我们优化的路径就好了。 那么好,按照它提供的theory,我们一步步问。第一步...