Packages, Interfaces, and Other Class Features - Java 6 - page 153

The org\cadenhead\library subfolder of the folder where the java command
was entered. (For example, if the command was made from the C:\J21work folder,
the BookShipper.class file could be run successfully if it was in the C:\J21work\
org\cadenhead\library folder.)

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The org\cadenhead\library subfolder of any folder in your Classpath setting.

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The org\cadenhead\library subfolder of a Java archive file (JAR) in your
Classpath .

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One way to manage your own packages and any others you use is to add a folder to your
Classpath that serves as the root folder for any packages you create or adopt, such as
C:\javapackages or something similar. After creating subfolders that correspond to the
name of a package, place the package's class files in the correct subfolder.

The import Declaration
To import classes from a package, use the import declaration as you have throughout the
examples in the first week. You can import an individual class, as in this statement:

import java.util.Vector;

You also can import an entire package of classes using an asterisk ( * ) in place of an indi-
vidual class name, like this:

import java.awt.*;

The asterisk can be used in place of a class name only in an import statement. It does
not make it possible to import multiple packages with similar names.

For example, the Java class library includes the java.util , java.util.jar , and
java.util.prefs packages. You could not import all three packages with the following
statement:

import java.util.*;

This merely imports the java.util package. To make all three available in a class, the
following statements are required:

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import java.util.*;
import java.util.jar.*;
import java.util.prefs.*;

Also, you cannot indicate partial class names (for example, L* to import all the classes
that begin with L). Your only options when using an import declaration are to load all
the classes in a package or just a single class.