synchronized section inside constructor and syncronized constructor differences

Question

I noticed interesting behaviour:

I can write

class My {
     public My(){
        synchronized(this){
            // code
        }

    }  
}

but I cannot write

class My {
         public synchronized My(){
                // code
            }

        }  
    }

I thought that both constructions works identically terms java API.

Please clarify this misunderstanding.

possible duplicate of [Why can't Java constructors be synchronized?](http://stackoverflow.com/questions/4880168/why-cant-java-constructors-be-synchronized) — rethab, Apr 28 '14 at 09:39

score 2 · Accepted Answer · answered Apr 28 '14 at 09:38

2

In the first case, the object is almost created, only the body of the Constructor need to executed.

But, in the second case, there won't any object to synchronize.

answered Apr 28 '14 at 09:38

just now I have understood that your answer is incorrect because constructor performed after initialize block. But inside initialize block I can write syncronized section with monitor this. What do you think ? – gstackoverflow Apr 28 '14 at 11:58
@gstackoverflow, before initialized block called, super class constructor will be executed and the object will almost created. – Abimaran Kugathasan Apr 28 '14 at 12:00
please realize my comment. – gstackoverflow Apr 28 '14 at 12:02
@gstackoverflow : You can do that, because, it's already completed it's super class constructor. – Abimaran Kugathasan Apr 28 '14 at 12:04

score 0 · Answer 2 · answered Apr 28 '14 at 12:00

0

It is impossible situation that two Threads will create same object !

Thus synchronized modificator hasn't sense for constructor.

answered Apr 28 '14 at 12:00

gstackoverflow

2 Answers2