Read Java concurrency Programming practice, adding functionality to a thread-safe class-Client Lock Implementation Example

In the Java Concurrency Programming practice, 4.4 mentions the method of locking the client. This is a validation example, but it is not good to write, but you can see the result.

 Packagecom.blackbread.test;Importjava.util.ArrayList;Importjava.util.Collections;Importjava.util.List;ImportJava.util.concurrent.ExecutorService;Importjava.util.concurrent.Executors; Public classGoodlisthelper<e> {     Publiclist<e> list = Collections.synchronizedlist (NewArraylist<e>());  Public BooleanPutifabsent (E x)throwsinterruptedexception {synchronized(list) {BooleanAbsent =!list.contains (x); if(absent) {if(List.contains (x)) System.out.println (List.contains (x));            List.add (x); }            returnabsent; }    }     Public classPrintAextendsThread {PrivateGoodlisthelper<string>Goodlisthelper; PrivateString value;  PublicPrintA (goodlisthelper<string>Goodlisthelper, String value) {             This. Goodlisthelper =Goodlisthelper;  This. Value =value; } @Override Public voidrun () {Try{goodlisthelper.putifabsent (value); } Catch(interruptedexception e) {e.printstacktrace (); }        }    }     Public classPrintbextendsThread {PrivateGoodlisthelper<string>Goodlisthelper; PrivateString value;  PublicPRINTB (goodlisthelper<string>Goodlisthelper, String value) {             This. Goodlisthelper =Goodlisthelper;  This. Value =value; } @Override Public voidrun () {goodListHelper.list.add (value); }    }     Public Static voidMain (string[] args)throwsinterruptedexception {FinalGoodlisthelper<string> Goodlisthelper =NewGoodlisthelper<string>(); NewThread (NewRunnable () {@Override Public voidrun () {Executorservice executor= Executors.newfixedthreadpool (50);  for(inti = 0; i < 1000; i++) {Thread T= Goodlisthelper.NewPrintA (Goodlisthelper, string.valueof (i));                Executor.execute (t);            } executor.shutdown ();        }}). Start (); NewThread (NewRunnable () {@Override Public voidrun () {Executorservice executor= Executors.newfixedthreadpool (50);  for(inti = 0; i < 1000; i++) {Thread T= Goodlisthelper.NewPrintb (Goodlisthelper, string.valueof (i));                Executor.execute (t);            } executor.shutdown ();    }}). Start (); }}

Read Java concurrency Programming practice, adding functionality to a thread-safe class-Client Lock Implementation Example