Semaphore implementation exception
0
$begingroup$
I am not sure why below code is throwing exception. If I implement the
same code with synchronized at method level then there is no
exception, and it works fine. I think using object lock should also
not have any issue.enter code here
package practice;
public class CustomSemaphore {
int count;
int capacity;
Object lock = new Object();
public CustomSemaphore(int capacity) {
this.count = capacity;
}
public void acquire() throws InterruptedException {
synchronized (lock) {
while (count > capacity) {
wait();
}
count++;
System.out.println(Thread.currentThread().getName() + " got lock and working now");
}
}
public void release() {
synchronized (lock) {
count--;
notify();
System.out.println("releasing resource now");
}
}
public static void main(String args) throws InterruptedException {
final CustomSemaphore sem = new CustomSemaphore(1);
Runnable acquireTask = new Runnable() {
@Override
public void run() {
while (true) {
try {
sem.acquire();
System.out.println(" acquired lock" + Thread.currentThread().getName());
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
};
Thread acqThread = new Thread(acquireTask, "acquire");
Runnable releaseTask = new Runnable() {
@Override
public void run() {
while (true) {
sem.release();
}
}
};
Thread releaseThread = new Thread(releaseTask, "release");
acqThread.start();
releaseThread.start();
acqThread.join();
releaseThread.join();
}
}
}
java multithreading concurrency
asked 24 mins ago
AKSAKS
1161
$endgroup$
add a comment |
0
$begingroup$
I am not sure why below code is throwing exception. If I implement the
same code with synchronized at method level then there is no
exception, and it works fine. I think using object lock should also
not have any issue.enter code here
package practice;
public class CustomSemaphore {
int count;
int capacity;
Object lock = new Object();
public CustomSemaphore(int capacity) {
this.count = capacity;
}
public void acquire() throws InterruptedException {
synchronized (lock) {
while (count > capacity) {
wait();
}
count++;
System.out.println(Thread.currentThread().getName() + " got lock and working now");
}
}
public void release() {
synchronized (lock) {
count--;
notify();
System.out.println("releasing resource now");
}
}
public static void main(String args) throws InterruptedException {
final CustomSemaphore sem = new CustomSemaphore(1);
Runnable acquireTask = new Runnable() {
@Override
public void run() {
while (true) {
try {
sem.acquire();
System.out.println(" acquired lock" + Thread.currentThread().getName());
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
};
Thread acqThread = new Thread(acquireTask, "acquire");
Runnable releaseTask = new Runnable() {
@Override
public void run() {
while (true) {
sem.release();
}
}
};
Thread releaseThread = new Thread(releaseTask, "release");
acqThread.start();
releaseThread.start();
acqThread.join();
releaseThread.join();
}
}
}
java multithreading concurrency
asked 24 mins ago
AKSAKS
1161
$endgroup$
add a comment |
0
0
0
$begingroup$
I am not sure why below code is throwing exception. If I implement the
same code with synchronized at method level then there is no
exception, and it works fine. I think using object lock should also
not have any issue.enter code here
package practice;
public class CustomSemaphore {
int count;
int capacity;
Object lock = new Object();
public CustomSemaphore(int capacity) {
this.count = capacity;
}
public void acquire() throws InterruptedException {
synchronized (lock) {
while (count > capacity) {
wait();
}
count++;
System.out.println(Thread.currentThread().getName() + " got lock and working now");
}
}
public void release() {
synchronized (lock) {
count--;
notify();
System.out.println("releasing resource now");
}
}
public static void main(String args) throws InterruptedException {
final CustomSemaphore sem = new CustomSemaphore(1);
Runnable acquireTask = new Runnable() {
@Override
public void run() {
while (true) {
try {
sem.acquire();
System.out.println(" acquired lock" + Thread.currentThread().getName());
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
};
Thread acqThread = new Thread(acquireTask, "acquire");
Runnable releaseTask = new Runnable() {
@Override
public void run() {
while (true) {
sem.release();
}
}
};
Thread releaseThread = new Thread(releaseTask, "release");
acqThread.start();
releaseThread.start();
acqThread.join();
releaseThread.join();
}
}
}
java multithreading concurrency
asked 24 mins ago
AKSAKS
1161
$endgroup$
I am not sure why below code is throwing exception. If I implement the
same code with synchronized at method level then there is no
exception, and it works fine. I think using object lock should also
not have any issue.enter code here
package practice;
public class CustomSemaphore {
int count;
int capacity;
Object lock = new Object();
public CustomSemaphore(int capacity) {
this.count = capacity;
}
public void acquire() throws InterruptedException {
synchronized (lock) {
while (count > capacity) {
wait();
}
count++;
System.out.println(Thread.currentThread().getName() + " got lock and working now");
}
}
public void release() {
synchronized (lock) {
count--;
notify();
System.out.println("releasing resource now");
}
}
public static void main(String args) throws InterruptedException {
final CustomSemaphore sem = new CustomSemaphore(1);
Runnable acquireTask = new Runnable() {
@Override
public void run() {
while (true) {
try {
sem.acquire();
System.out.println(" acquired lock" + Thread.currentThread().getName());
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
};
Thread acqThread = new Thread(acquireTask, "acquire");
Runnable releaseTask = new Runnable() {
@Override
public void run() {
while (true) {
sem.release();
}
}
};
Thread releaseThread = new Thread(releaseTask, "release");
acqThread.start();
releaseThread.start();
acqThread.join();
releaseThread.join();
}
}
}
java multithreading concurrency
java multithreading concurrency
asked 24 mins ago
AKSAKS
1161
asked 24 mins ago
AKSAKS
1161
asked 24 mins ago
AKSAKS
1161
asked 24 mins ago
AKSAKS
1161
asked 24 mins ago
AKSAKS
1161
1161
add a comment |
add a comment |
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