public boolean tryLock(final byte[] ctx) {
        return internalTryLock(ctx).isSuccess();
    }
Acquires the lock only if it is free at the time of invocation.

Acquires the lock if it is available and returns immediately
with the value {@code true}.
If the lock is not available then this method will return
immediately with the value {@code false}.

@param ctx the context of current lock request
@return {@code true} if the lock was acquired and {@code false}
otherwise
jraft-rheakv/rheakv-core/src/main/java/com/alipay/sofa/jraft/rhea/util/concurrent/DistributedLock.java