new に類似した単純なフェア ロックを作成する方法はReentrantLock(true)
?
public class Main1 {
public static void main(String[] args) {
// Lock lock = new ReentrantLock(true);
CustomLock lock = new CustomLock();
new Thread(new Producer(lock)).start();
new Thread(new Consumer(lock)).start();
}
}
class Producer implements Runnable {
private Lock lock;
private CustomLock customLock;
public Producer(Lock lock) {
this.lock = lock;
}
public Producer(CustomLock lock) {
this.customLock = lock;
}
@Override
public void run() {
while (!Thread.currentThread().isInterrupted()) {
// lock.lock();
customLock.lock();
System.out.println("Producer before");
try {
TimeUnit.SECONDS.sleep(1);
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println("Producer after");
// lock.unlock();
customLock.unlock();
}
}
}
class Consumer implements Runnable {
private Lock lock;
private CustomLock customLock;
public Consumer(Lock lock) {
this.lock = lock;
}
public Consumer(CustomLock lock) {
this.customLock = lock;
}
@Override
public void run() {
while (!Thread.currentThread().isInterrupted()) {
// lock.lock();
customLock.lock();
System.out.println("Consumer before");
try {
TimeUnit.SECONDS.sleep(1);
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println("Consumer after");
// lock.unlock();
customLock.unlock();
}
}
}
class CustomLock{
private boolean isLocked;
public synchronized void lock(){
while (isLocked) {
try {
wait();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
isLocked = true;
}
public synchronized void unlock(){
if(isLocked){
isLocked = false;
notify();
}
}
}
Custom not fair Lock (それが正しいかどうかはわかりません)
class CustomLock{
private boolean isLocked;
public synchronized void lock(){
while (isLocked) {
try {
wait();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
isLocked = true;
}
public synchronized void unlock(){
if(isLocked){
isLocked = false;
notify();
}
}
}