Understanding condition thread communication through a face question

Condition

• The condition interface describes the condition variables that may be associated with a lock. These variables are similar in usage to implicit monitors that use object.wait access, but provide more powerful functionality. It should be noted that a single lock may be associated with multiple condition objects. To avoid compatibility issues, the name of the condition method differs from the corresponding object version;
• In the condition object, the await, signal, and signalall correspond to the wait, notify, and Notifyall methods respectively;
• The condition instance is essentially bound to a lock. To obtain an condition instance for a particular lock instance, use the Newcondition () method.

Interview questions

1  PackageCom.ccfdod.juc;2 3 Importjava.util.concurrent.locks.Condition;4 ImportJava.util.concurrent.locks.Lock;5 ImportJava.util.concurrent.locks.ReentrantLock;6 7 /**8 * Title: Write a program to open 3 threads, the IDs of the three threads are a, B, C, each thread prints its own ID on the screen 10 times, and requires the output to be displayed sequentially. 9 * such as: Abcabcabc ...Ten */ One classAlternatedemo { A     //flag is currently output by which thread, 1 represents a,2 on behalf of b,3 for C -     Private intNumber = 1; -  theLock lock =NewReentrantlock (); -  -     //the power of condition is that it can create different condition for multiple threads -Condition Condition1 =lock.newcondition (); +Condition Condition2 =lock.newcondition (); -Condition Condition3 =lock.newcondition (); +  A     //Loopnum: Current number of circular wheels at      Public voidLoopA (intloopnum) { -         //locked - Lock.lock (); -         Try { -              while(Number! = 1) { -                 //wait in condition1.await (); -             } to  +System.out.println (Thread.CurrentThread (). GetName () + ", Currentloopnum is" +loopnum); -Number = 2; the             //Wake up * condition2.signal (); $ Panax Notoginseng}Catch(interruptedexception e) { - e.printstacktrace (); the}finally { +             //make sure to release the lock A Lock.unlock (); the         } +     } -  $      Public voidLOOPB (intloopnum) { $ Lock.lock (); -         Try { -              while(Number! = 2) { the condition2.await (); -             }Wuyi  theSystem.out.println (Thread.CurrentThread (). GetName () + ", Currentloopnum is" +loopnum); -Number = 3; Wu condition3.signal (); -  About}Catch(interruptedexception e) { $ e.printstacktrace (); -}finally { - Lock.unlock (); -         } A     } +  the      Public voidLOOPC (intloopnum) { - Lock.lock (); $         Try { the              while(Number! = 3) { the condition3.await (); the             } the  -System.out.println (Thread.CurrentThread (). GetName () + ", Currentloopnum is" +loopnum); inNumber = 1; the condition1.signal (); the  About}Catch(interruptedexception e) { the e.printstacktrace (); the}finally { the Lock.unlock (); +         } -     } the }Bayi  the  Public classTestabcalternate { the  -      Public Static voidMain (string[] args) { -Alternatedemo AD =NewAlternatedemo (); the  the         NewThread (NewRunnable () { the  the @Override -              Public voidrun () { the                  for(inti = 0; I < 10; i++) the Ad.loopa (i); the             }94}, "A"). Start (); the  the         NewThread (NewRunnable () { the 98 @Override About              Public voidrun () { -                  for(inti = 0; I < 10; i++)101 AD.LOOPB (i);102             }103}, "B"). Start ();104  the         NewThread (NewRunnable () {106 107 @Override108              Public voidrun () {109                  for(inti = 0; I < 10; i++) the Ad.loopc (i);111             } the}, "C"). Start ();113     } the}

Understanding condition thread communication through a face question