摘要：Program order rule. Each action in a thread happens-before every action in that thread that comes later in the program order.Monitor lock rule. An unlock on a monitor lock happens-before every subsequent lock on that same monitor lock.Volatile variable rule. A write to a volatile field happens-befor 阅读全文

摘要：Perhaps surprisingly, concurrent programming isn’t so much about threads or locks, any more than civil engineering is about rivets and I-beams. Of course,building bridges that don’t fall down requires the correct use of a lot of rivets and I-beams, just as building concurrent programs require the co 阅读全文

摘要：Preface前言At this writing, multicore processors are just now becoming inexpensive enough for midrange desktop systems. Not coincidentally, many development teams are noticing more and more threading-related bug reports in their projects. In a recent post on the NetBeans developer site, one of the cor 阅读全文

摘要：单例模式在Java编程实践中经常用到。单例模式用于保证每个类只有一个实例存在。本文将对Java单利模式进行一个系统深入的介绍。单例模式是为了保证一个类只有一个实例存在。注意，我们所说的每个类只有一个实例存在是相对于一个JVM和一个ClassLoader而言的。由于不同的类装载器装载的类位于不同的命名空间内，所以在同一个JVM还是可以有有不同的类装载器装载的不同的实例。但这些实例是不同的。测试:先建立如下Singleton类:public class Singleton { private static Singleton instance = new Singleton(); ... 阅读全文

摘要：问题：请问下面的那种方法能正确地把字符"B"从集合stringList中删除掉?1 List<String> stringList = new ArrayList<String>();2 stringList.add("A");3 stringList.add("B");4 stringList.add("C");5 stringList.add("B");6 stringList.add("D");7 stringList.add("E&q 阅读全文

摘要：问题:有一个类Foo如下:public class Foo{ private int i = 0; public void f(){ System.println("In f() i=" + i); } public synchronized void g(){ //point 1 System.println("In g() i=" + i); i = 1; //point 2 System.println("In g() i=" + i); }}请问如果有两个线程A,B,线程B执行到point 2时,问线程A总会打印出" 阅读全文

摘要：3.3.3 ThreadLocal3.3.3 ThreadLocalA more formal means of maintaining thread confinement is ThreadLocal,which allows you to associate a per-thread value with a value-holding object. ThreadLocal provides get and set accessor methods that maintain a separate copy of the value for each thread that use... 阅读全文

摘要：Explicit LocksExplicit LockBefore Java 5.0, the only mechanisms for coordinating access to shared data were synchronized and volatile. Java 5.0 adds another option: ReentrantLock.Contrary to what some have written, ReentrantLock is not a replacement for intrinsic locking, but rather an alternative w 阅读全文