The default builder is no argument. Their role is to create an "empty object". If you create a class without a builder, the compiler will help us automatically create a default builder.
Class bird {
INT I;
}
public
Class defaultconstructor {
public
Static
Void main (string [] args) {
Bird nc =
NEW bird ();
// default!
}
For the following line:
NEW bird ();
Its role is to create a new object and call the default builder - even if there is not clearly defined a builder like this. If there is no, there is no way to call, and our object cannot be constructed. However, if a builder has been defined (whether or not there is a variety of variables), the compiler will not help us automatically synthesize:
Class bush {
Bush (INT I) {}
Bush (double d) {}
}
Now, if you use the following code:
New bush ();
The compiler will report that you can't find a constructed builder. Just as we have no builder, the compiler will say: "You seem to need a builder, so let us create one." But if we wrote a builder, the compiler will say: "Ah, you have written a builder, so I know what you want; if you don't place a default, it is because you intend to omit it."
