Merge remote-tracking branch 'origin/master'

Author: winterbe

src/com/winterbe/java8/samples/concurrent/Lock4.java

@@ -0,0 +1,59 @@
+packagecom.winterbe.java8.samples.concurrent;
+
+importjava.util.concurrent.ExecutorService;
+importjava.util.concurrent.Executors;
+importjava.util.concurrent.TimeUnit;
+importjava.util.concurrent.locks.StampedLock;
+
+/**
+ * @author Benjamin Winterberg
+ */
+publicclassLock4{
+
+privatestaticintcount = 0;
+
+publicstaticvoidmain(String[] args){
+ExecutorServiceexecutor = Executors.newFixedThreadPool(2);
+
+StampedLocklock = newStampedLock();
+
+executor.submit(() ->{
+longstamp = lock.writeLock();
+try{
+count++;
+TimeUnit.SECONDS.sleep(1);
+ } catch (InterruptedExceptione){
+thrownewIllegalStateException(e);
+ } finally{
+lock.unlockWrite(stamp);
+ }
+ });
+
+executor.submit(() ->{
+longstamp = lock.readLock();
+try{
+System.out.println(Thread.currentThread().getName() + ": " + count);
+TimeUnit.SECONDS.sleep(1);
+ } catch (InterruptedExceptione){
+thrownewIllegalStateException(e);
+ } finally{
+lock.unlockRead(stamp);
+ }
+ });
+
+executor.submit(() ->{
+longstamp = lock.readLock();
+try{
+System.out.println(Thread.currentThread().getName() + ": " + count);
+TimeUnit.SECONDS.sleep(1);
+ } catch (InterruptedExceptione){
+thrownewIllegalStateException(e);
+ } finally{
+lock.unlockRead(stamp);
+ }
+ });
+
+ConcurrentUtils.stop(executor);
+ }
+
+}

src/com/winterbe/java8/samples/concurrent/Lock5.java

@@ -0,0 +1,56 @@
+packagecom.winterbe.java8.samples.concurrent;
+
+importjava.util.concurrent.ExecutorService;
+importjava.util.concurrent.Executors;
+importjava.util.concurrent.TimeUnit;
+importjava.util.concurrent.locks.StampedLock;
+
+/**
+ * @author Benjamin Winterberg
+ */
+publicclassLock5{
+
+privatestaticintcount = 0;
+
+publicstaticvoidmain(String[] args){
+ExecutorServiceexecutor = Executors.newFixedThreadPool(2);
+
+StampedLocklock = newStampedLock();
+
+executor.submit(() ->{
+longstamp = lock.tryOptimisticRead();
+try{
+System.out.println("Optimistic Lock Valid: " + lock.validate(stamp));
+TimeUnit.SECONDS.sleep(1);
+System.out.println("Optimistic Lock Valid: " + lock.validate(stamp));
+ } catch (InterruptedExceptione){
+thrownewIllegalStateException(e);
+ } finally{
+lock.unlock(stamp);
+ }
+ });
+
+executor.submit(() ->{
+longstamp = lock.writeLock();
+try{
+System.out.println("Write Lock acquired");
+incrementAndSleep(2);
+ } finally{
+lock.unlock(stamp);
+System.out.println("Write done");
+ }
+ });
+
+
+ConcurrentUtils.stop(executor);
+ }
+
+privatestaticvoidincrementAndSleep(intsleepSeconds){
+try{
+count++;
+TimeUnit.SECONDS.sleep(sleepSeconds);
+ } catch (InterruptedExceptione){
+thrownewIllegalStateException(e);
+ }
+ }
+}

src/com/winterbe/java8/samples/concurrent/Lock6.java

@@ -0,0 +1,39 @@
+packagecom.winterbe.java8.samples.concurrent;
+
+importjava.util.concurrent.ExecutorService;
+importjava.util.concurrent.Executors;
+importjava.util.concurrent.locks.StampedLock;
+
+/**
+ * @author Benjamin Winterberg
+ */
+publicclassLock6{
+
+privatestaticintcount = 0;
+
+publicstaticvoidmain(String[] args){
+ExecutorServiceexecutor = Executors.newFixedThreadPool(2);
+
+StampedLocklock = newStampedLock();
+
+executor.submit(() ->{
+longstamp = lock.readLock();
+try{
+if (count == 0){
+stamp = lock.tryConvertToWriteLock(stamp);
+if (stamp == 0L){
+System.out.println("Could not convert to write lock");
+stamp = lock.writeLock();
+ }
+count = 23;
+ }
+System.out.println(count);
+ } finally{
+lock.unlock(stamp);
+ }
+ });
+
+ConcurrentUtils.stop(executor);
+ }
+
+}