7.6

Type Declarations

PACKAGES

import Vector.Mosquito;

class Test {

public static void main(String[] args) {

System.out.println(new Vector().getClass());

System.out.println(new Mosquito().getClass());

}

}

the single type import declaration ( 7.5.1) importing class

Vector

 from package

java.util

 does not prevent the package name

Vector

 from appearing and being

correctly recognized in subsequent

import

 declarations. The example compiles

and produces the output:

class java.util.Vector

class Vector.Mosquito

7.6   Type Declarations

A type declaration declares a class type ( 8) or an interface type ( 9):

TypeDeclaration:

ClassDeclaration

InterfaceDeclaration

;

A Java compiler must ignore extra  

;

  tokens appearing at the level of type

declarations. Stray semicolons are permitted in Java solely as a concession to C++

programmers who are used to writing:

class date { int month, day, year; };

(In C++, but not in Java, one can provide a comma separated list of identifiers in

order to declare variables between the  

}

  and the  

;

 .) Extra semicolons should

not be used in new Java code. Software that reformats Java code can delete them.

By default, the types declared in a package are accessible only within the

compilation units of that package, but a type may be declared to be

public

 to

grant access to the type from code in other packages ( 6.6,  8.1.2,  9.1.2).

A Java implementation must keep track of types within packages by their

fully qualified names ( 6.7). Multiple ways of naming a type must be expanded to

fully qualified names to make sure that such names are understood as referring to

the same type. For example, if a compilation unit contains the single type import

declaration ( 7.5.1):

import java.util.Vector;

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