Importing classes and packages

To reference a class in another script, you must prefix the class name with the class's package name. The combination of a class's name and its package path is the class's fully qualified class name. If a class resides in a top-level classpath directory--not in a subdirectory in the classpath directory--then its class name is also its fully qualified class name.

To specify package paths, use dot (.) notation to separate package directory names. Package paths are hierarchical; that is, each dot represents a nested directory. For example, suppose you create a class named ClassName that resides in a com/adobe/docs/learnAs2 package in your classpath. To create an instance of that class, you could specify the fully qualified class name.

You can also use the fully qualified class name to type your variables, as shown in the following example:

var myInstance:com.adobe.docs.learnAs2.ClassName = new com.adobe.docs.learnAs2.ClassName();

You can use the import statement to import packages into a script, which lets you use a class's abbreviated name rather than its fully qualified name. You can also use the wildcard character (*) to import all the classes in a package. If you use the wildcard character, you don't need to use the fully qualified class name each time you use the class.

For example, suppose that in a script you imported the above class using the import statement, as shown in the following example:

Later, in the same script, you could reference that class by its abbreviated name, as shown in the following example:

You can use the wildcard character (*) to import all the classes in a given package. Suppose you have a package named com.adobe.utils that contains two ActionScript class files, ClassA.as and ClassB.as. In another script, you could import both classes in that package using the wildcard character, as shown in the following code:

The following example shows that you can then reference either of the classes directly in the same script:

The import statement applies only to the current script (frame or object) in which it's called. If an imported class is not used in a script, the class is not included in the resulting SWF file's bytecode, and the class isn't available to any SWF files that the FLA file containing the import statement might load.

To import a class or package:

Open the file called package_test.fla.
Type the following code into the Script window:
```
import com.adobe.utils.*;
var a = new ClassA(); // ClassA constructor
var b = new ClassB(); // ClassB constructor
```
The previous block of code begins by importing each of the classes within the com.adobe.utils package by using the wildcard (*) character. Next, you create a new instance of the ClassA class, which causes the constructor method to trace a message to the Output panel. An instance of the ClassB class is also created, which sends debugging messages to the Output panel.
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