C++ vs Java constructors

Question

According to John C. Mitchell - Concepts in programming languages,

[...] Java guarantees that a constructor is called whenever an object is created.

Answer 1

Only When you overload new operator function then constructor is not called (it used to avoid constructor calling), else its in standard that constructor is invoked when object is created.

void * operator new ( size_t size )
{

     void *p = malloc(size);

     if(p)
       return p; 
     else
        cout<(operator new(sizeof(X)*5)); // no ctor called

}