java - Benefits of using ReentrantLock over synchronized -

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• side effects of throwing exception inside synchronized clause? 2 answers

i find out 1 more benefit of using reentrantlock on synchronized

below code shows if exception occurs in critical section lock released(using reentrantlock )

void somemethod() {      //get lock before processing critical section.    lock.lock();    try     {    // critical section     //if exception occurs    }       {    //releasing lock other threads can notifies    lock.unlock();    } }//end of method 

now using synchronized

void somemethod() {      //get lock before processing critical section.   synchronized(this)    {     try      {     // critical section      //if exception occurs     }         {     //i don't know how release lock      }   }  }//end of method 

by comparing both code see there 1 more disadvantage in using synchronized block i.e if exception occurs in critical section not possible release lock.

am right ?

correct me if wrong please.

is there anyway release lock if exception occurrs in synchronized block ?

if exception occurs in synchronized block lock still released. lock released in circumstances.

the advantage reentrantlock use compare , sweep performs better in low contention.