Java Reference
In-Depth Information
System.out.println(e);
}
}
}
}
This program produces the output:
1
2
before causing a
NullPointerException
in trying to index the second component of the ar-
ray
ia
, which is a null reference.
10.7. Array Members
The members of an array type are all of the following:
• The
public final
field
length
, which contains the number of components of the array.
length
may be positive or zero.
• The
public
method
clone
, which overrides the method of the same name in class
Ob-
ject
and throws no checked exceptions. The return type of the
clone
method of an ar-
ray type
T
[]
is
T
[]
.
A clone of a multidimensional array is shallow, which is to say that it creates only
a single new array. Subarrays are shared.
• All the members inherited from class
Object
; the only method of
Object
that is not
inherited is its
clone
method.
An array thus has the same
public
fields and methods as the following class:
class A<T> implements Cloneable, java.io.Serializable {
public final int length = X ;
public T[] clone() {
try {
return (T[])super.clone(); // unchecked warning
} catch (CloneNotSupportedException e) {
throw new InternalError(e.getMessage());
}
}
}
Note that the cast in the example above would generate an unchecked warning