I want to implement lazy initialization for multithreading in Java.
I have some code of the sort:

class Foo { private Helper helper = null; public Helper getHelper() { if (helper == null) { Helper h; synchronized(this) { h = helper; if (h == null) synchronized (this) { h = new Helper(); } // release inner synchronization lock helper = h; } } return helper; } // other functions and members... } 

And I'm getting the the "Double-Checked Locking is Broken" declaration.
How can I solve this?

I want to implement lazy initialization for multithreading in Java.
I have some code of the sort:

class Foo { private Helper helper = null; public Helper getHelper() { if (helper == null) { Helper h; synchronized(this) { h = helper; if (h == null) synchronized (this) { h = new Helper(); } // release inner synchronization lock helper = h; } } return helper; } // other functions and members... } 

And I'm getting the the "Double-Checked Locking is Broken" declaration.
How can I solve this?