Introduction to the use of Blockingqueue based on Java _java

Recently in the maintenance of a Java project, in the group also chat up the pros and cons of Java! But some of the ultimate Java fans, always known as performance has no need for C + +, and many standard class libraries are master-level people write, how to stabilize and so on. Simply to study it carefully, they gave me a note is that the message between the threads, with Java has been encapsulated good blockingqueue, it is enough to use.

Since it's enough to write code tests, simply write a small program to do a test:

Copy Code code as follows:

Default Package
Import java.util.concurrent.*;

Import base. myrunnable;

public class Test
{
public static void Main (string[] args)
{
blockingqueue<integer> queue = new linkedblockingqueue<integer> ();
java.lang.Runnable r = new myrunnable (queue);
Thread t = new Thread (r);
T.start ();

while (true)
{
Try
{
while (true)
{
for (int i =0;i < 10000;i++)
{
Queue.offer (i);
}
}
}
catch (Exception e)
{
E.printstacktrace ();
}
}
}
}


Packages that need to be added
Package base;

Import java.lang.Runnable;
Import java.util.concurrent.*;
Import java.util.*;

public class Myrunnable implements Runnable
{
Public myrunnable (blockingqueue<integer> queue)
{
This.queue = queue;
}
public void Run ()
{
Date d = new Date ();
Long starttime = D.gettime ();
System.err.println (starttime);
int count = 0;
while (true)
{
Try
{
Integer i = This.queue.poll ();
if (i!= null)
{
Count + +;
}
if (count = = 100000)
{
Date E = new Date ();
Long endtime = E.gettime ();
System.err.println (count);
System.err.println (Endtime);
System.err.print (Endtime-starttime);
Break
}

}
catch (Exception e)
{

}
}
}
Private blockingqueue<integer> queue;
}

Pass 100,000 data, on my test machine, probably need about 50ms, but also can! Just looked at the bottom of the Blockingqueue implementation

The offer and poll I used in the test code above, look at these two implementations, first of all, an offer.

Copy Code code as follows:

Public E poll () {
Final Atomicinteger count = This.count;
if (count.get () = = 0)
return null;
E x = null;
int c =-1;
Final Reentrantlock takelock = This.takelock;
Takelock.lock ();
try {
if (Count.get () > 0) {
x = Extract ();
c = count.getanddecrement ();
if (C > 1)
Notempty.signal ();
}
finally {
Takelock.unlock ();
}
if (c = = capacity)
Signalnotfull ();
return x;
}

Similar to the general synchronization thread, just add a signal, in learning UNIX environment advanced programming, see the condition variable for the synchronization between the threads, you can achieve the thread in a competitive way to achieve synchronization!
The implementation of the poll function is similar!

Copy Code code as follows:

Public Boolean offer (E e) {
if (E = = null) throw new NullPointerException ();
Final Atomicinteger count = This.count;
if (count.get () = = capacity)
return false;
int c =-1;
Final Reentrantlock putlock = This.putlock;
Putlock.lock ();
try {
if (Count.get () < capacity) {
Insert (e);
c = count.getandincrement ();
if (c + 1 < capacity)
Notfull.signal ();
}
finally {
Putlock.unlock ();
}
if (c = = 0)
Signalnotempty ();
return c >= 0;
}