再学JAVA基礎(六):マルチスレッドの同期
9708 ワード
1.synchronizedキーワード
2.volatileキーワード
3.ロックロック
4.Mutex信号量
/**
*
* @author tomsnail
* @date 2015 4 18 12:12:39
*/
public class SyncThreadTest {
private static final byte[] lock = new byte[1];
/**
*
* @author tomsnail
* @date 2015 4 18 12:15:30
*/
public synchronized void test1(){
}
/**
*
* @author tomsnail
* @date 2015 4 18 12:15:17
*/
public void test2(){
synchronized (lock) {
}
}
}2.volatileキーワード
/**
* volatile
* @author tomsnail
* @date 2015 4 18 12:21:58
*/
public class VolatileThreadTest {
private volatile int count = 100;
public void add(int number){
count+=number;
}
public int getCount(){
return count;
}
}3.ロックロック
/**
* lock
* @author tomsnail
* @date 2015 4 18 12:58:49
*/
public class LockThreadTest {
private Lock lock = new ReentrantLock();
private int count = 100;
public void test(){
lock.lock();
count++;
System.out.println(count);
lock.unlock();
}
}4.Mutex信号量
/**
*
* @author tomsnail
* @date 2015 4 18 1:14:47
*/
public class MutexThreadTest {
private CountDownLatch countDownLatch = new CountDownLatch(1);
private Semaphore s = new Semaphore(5);
public void a(){
try {
countDownLatch.await();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
public void b(){
countDownLatch.countDown();
}
public void c(){
try {
System.out.println(" try acquire s");
s.acquire();
System.out.println(" acquire s");
} catch (InterruptedException e) {
e.printStackTrace();
}
}
public void d(){
s.release();
System.out.println(" release s");
}
public static void main(String[] args) {
MutexThreadTest mutexThreadTest = new MutexThreadTest();
for(int i=0;i<10;i++){
new Thread(new ThreadTest(mutexThreadTest)).start();
}
mutexThreadTest.a();
System.out.println("a...");
for(int i=0;i<10;i++){
new Thread(new ThreadTest2(mutexThreadTest)).start();
}
}
}
class ThreadTest implements Runnable{
private MutexThreadTest mutexThreadTest;
public ThreadTest(MutexThreadTest mutexThreadTest){
this.mutexThreadTest = mutexThreadTest;
}
@Override
public void run() {
try {
Thread.currentThread().sleep(500);
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println("mutexThreadTest countDown");
mutexThreadTest.b();
}
}
class ThreadTest2 implements Runnable{
private MutexThreadTest mutexThreadTest;
public ThreadTest2(MutexThreadTest mutexThreadTest){
this.mutexThreadTest = mutexThreadTest;
}
@Override
public void run() {
mutexThreadTest.c();
try {
Thread.currentThread().sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
mutexThreadTest.d();
}
}