Critical section around given key
1
$begingroup$
I would like to know if there is any pre-existing implmentation of my solution. So I don't have to reinvent the wheel.
What I'm trying to create is an utility which allows me to create critical section around given object. Can you check my code if there are any errors in my implemention?
import java.util.concurrent.Callable;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.locks.ReentrantLock;
public class MultiCriticalSection {
private final ConcurrentHashMap<Object, ExtendReentrantLock> locks = new ConcurrentHashMap<>();
private final Object globalLock = new Object();
/**
* Run critical section guarded by given object. It is potentionally blocking code!
*/
public <T> T doWithLock(final Object key, Callable<T> fce) throws Exception {
ExtendReentrantLock lock = getLock(key);
try {
return fce.call();
} finally {
freeLock(key, lock);
}
}
/**
* Run critical section guarded by given object. It is potentionally blocking code!
*/
public void doWithLock(final Object key, Runnable fce) {
ExtendReentrantLock lock = getLock(key);
try {
fce.run();
} finally {
freeLock(key, lock);
}
}
/**
* Release the lock. If there are no threads waiting and the lock is marked for removal it will be removed.
*/
private void freeLock(final Object key, final ExtendReentrantLock lock) {
synchronized (globalLock) {
if (!lock.hasQueuedThreads() && lock.remove) {
locks.remove(key);
}
lock.remove = true;
lock.unlock();
}
}
/**
* Acquire lock. If there are no locks for given object it is created.
* If there is a lock for given object and it is locked the removal flag is cleared. This way the currently running thread will not
* remove the lock from memory.
*/
private ExtendReentrantLock getLock(final Object key) {
ExtendReentrantLock lock;
synchronized (globalLock) {
lock = locks.computeIfAbsent(key, o -> new ExtendReentrantLock());
if (lock.isLocked()) {
lock.remove = false;
}
}
lock.lock();
return lock;
}
/**
* Utility class adding a flag to ReentrantLock.
*/
private class ExtendReentrantLock extends ReentrantLock {
boolean remove = true;
}
}
The goal is not to allow 2 concurrent threads to operate on the same data. That is only one object can operate on given object at same time.
The other thread will be blocked, until the working thread is finished. The locks are automatically cleared when there are no threads running.
Thanks for any tips.
java concurrency locking
asked 1 hour ago
cervotoccervotoc
61
New contributor
cervotoc is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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add a comment |
1
$begingroup$
I would like to know if there is any pre-existing implmentation of my solution. So I don't have to reinvent the wheel.
What I'm trying to create is an utility which allows me to create critical section around given object. Can you check my code if there are any errors in my implemention?
import java.util.concurrent.Callable;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.locks.ReentrantLock;
public class MultiCriticalSection {
private final ConcurrentHashMap<Object, ExtendReentrantLock> locks = new ConcurrentHashMap<>();
private final Object globalLock = new Object();
/**
* Run critical section guarded by given object. It is potentionally blocking code!
*/
public <T> T doWithLock(final Object key, Callable<T> fce) throws Exception {
ExtendReentrantLock lock = getLock(key);
try {
return fce.call();
} finally {
freeLock(key, lock);
}
}
/**
* Run critical section guarded by given object. It is potentionally blocking code!
*/
public void doWithLock(final Object key, Runnable fce) {
ExtendReentrantLock lock = getLock(key);
try {
fce.run();
} finally {
freeLock(key, lock);
}
}
/**
* Release the lock. If there are no threads waiting and the lock is marked for removal it will be removed.
*/
private void freeLock(final Object key, final ExtendReentrantLock lock) {
synchronized (globalLock) {
if (!lock.hasQueuedThreads() && lock.remove) {
locks.remove(key);
}
lock.remove = true;
lock.unlock();
}
}
/**
* Acquire lock. If there are no locks for given object it is created.
* If there is a lock for given object and it is locked the removal flag is cleared. This way the currently running thread will not
* remove the lock from memory.
*/
private ExtendReentrantLock getLock(final Object key) {
ExtendReentrantLock lock;
synchronized (globalLock) {
lock = locks.computeIfAbsent(key, o -> new ExtendReentrantLock());
if (lock.isLocked()) {
lock.remove = false;
}
}
lock.lock();
return lock;
}
/**
* Utility class adding a flag to ReentrantLock.
*/
private class ExtendReentrantLock extends ReentrantLock {
boolean remove = true;
}
}
The goal is not to allow 2 concurrent threads to operate on the same data. That is only one object can operate on given object at same time.
The other thread will be blocked, until the working thread is finished. The locks are automatically cleared when there are no threads running.
Thanks for any tips.
java concurrency locking
asked 1 hour ago
cervotoccervotoc
61
New contributor
cervotoc is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
add a comment |
1
1
1
1
$begingroup$
I would like to know if there is any pre-existing implmentation of my solution. So I don't have to reinvent the wheel.
What I'm trying to create is an utility which allows me to create critical section around given object. Can you check my code if there are any errors in my implemention?
import java.util.concurrent.Callable;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.locks.ReentrantLock;
public class MultiCriticalSection {
private final ConcurrentHashMap<Object, ExtendReentrantLock> locks = new ConcurrentHashMap<>();
private final Object globalLock = new Object();
/**
* Run critical section guarded by given object. It is potentionally blocking code!
*/
public <T> T doWithLock(final Object key, Callable<T> fce) throws Exception {
ExtendReentrantLock lock = getLock(key);
try {
return fce.call();
} finally {
freeLock(key, lock);
}
}
/**
* Run critical section guarded by given object. It is potentionally blocking code!
*/
public void doWithLock(final Object key, Runnable fce) {
ExtendReentrantLock lock = getLock(key);
try {
fce.run();
} finally {
freeLock(key, lock);
}
}
/**
* Release the lock. If there are no threads waiting and the lock is marked for removal it will be removed.
*/
private void freeLock(final Object key, final ExtendReentrantLock lock) {
synchronized (globalLock) {
if (!lock.hasQueuedThreads() && lock.remove) {
locks.remove(key);
}
lock.remove = true;
lock.unlock();
}
}
/**
* Acquire lock. If there are no locks for given object it is created.
* If there is a lock for given object and it is locked the removal flag is cleared. This way the currently running thread will not
* remove the lock from memory.
*/
private ExtendReentrantLock getLock(final Object key) {
ExtendReentrantLock lock;
synchronized (globalLock) {
lock = locks.computeIfAbsent(key, o -> new ExtendReentrantLock());
if (lock.isLocked()) {
lock.remove = false;
}
}
lock.lock();
return lock;
}
/**
* Utility class adding a flag to ReentrantLock.
*/
private class ExtendReentrantLock extends ReentrantLock {
boolean remove = true;
}
}
The goal is not to allow 2 concurrent threads to operate on the same data. That is only one object can operate on given object at same time.
The other thread will be blocked, until the working thread is finished. The locks are automatically cleared when there are no threads running.
Thanks for any tips.
java concurrency locking
asked 1 hour ago
cervotoccervotoc
61
New contributor
cervotoc is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
I would like to know if there is any pre-existing implmentation of my solution. So I don't have to reinvent the wheel.
What I'm trying to create is an utility which allows me to create critical section around given object. Can you check my code if there are any errors in my implemention?
import java.util.concurrent.Callable;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.locks.ReentrantLock;
public class MultiCriticalSection {
private final ConcurrentHashMap<Object, ExtendReentrantLock> locks = new ConcurrentHashMap<>();
private final Object globalLock = new Object();
/**
* Run critical section guarded by given object. It is potentionally blocking code!
*/
public <T> T doWithLock(final Object key, Callable<T> fce) throws Exception {
ExtendReentrantLock lock = getLock(key);
try {
return fce.call();
} finally {
freeLock(key, lock);
}
}
/**
* Run critical section guarded by given object. It is potentionally blocking code!
*/
public void doWithLock(final Object key, Runnable fce) {
ExtendReentrantLock lock = getLock(key);
try {
fce.run();
} finally {
freeLock(key, lock);
}
}
/**
* Release the lock. If there are no threads waiting and the lock is marked for removal it will be removed.
*/
private void freeLock(final Object key, final ExtendReentrantLock lock) {
synchronized (globalLock) {
if (!lock.hasQueuedThreads() && lock.remove) {
locks.remove(key);
}
lock.remove = true;
lock.unlock();
}
}
/**
* Acquire lock. If there are no locks for given object it is created.
* If there is a lock for given object and it is locked the removal flag is cleared. This way the currently running thread will not
* remove the lock from memory.
*/
private ExtendReentrantLock getLock(final Object key) {
ExtendReentrantLock lock;
synchronized (globalLock) {
lock = locks.computeIfAbsent(key, o -> new ExtendReentrantLock());
if (lock.isLocked()) {
lock.remove = false;
}
}
lock.lock();
return lock;
}
/**
* Utility class adding a flag to ReentrantLock.
*/
private class ExtendReentrantLock extends ReentrantLock {
boolean remove = true;
}
}
The goal is not to allow 2 concurrent threads to operate on the same data. That is only one object can operate on given object at same time.
The other thread will be blocked, until the working thread is finished. The locks are automatically cleared when there are no threads running.
Thanks for any tips.
java concurrency locking
java concurrency locking
asked 1 hour ago
cervotoccervotoc
61
New contributor
cervotoc is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 1 hour ago
cervotoccervotoc
61
New contributor
cervotoc is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 1 hour ago
cervotoccervotoc
61
New contributor
cervotoc is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 1 hour ago
cervotoccervotoc
61
asked 1 hour ago
cervotoccervotoc
61
61
New contributor
cervotoc is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
cervotoc is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
cervotoc is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
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