You use the component compiler to generate a SWC file from component source files and other asset files such as images and style sheets. A SWC file is an archive of Flex components and other assets. For more information about SWC files, see About SWC files.

In some ways, the component compiler is similar to the application compiler. The application compiler produces a SWF file from one or more MXML and ActionScript files; the component compiler produces a SWC file from its input files. SWC files are compressed files that contain a SWF file (library.swf), asset files, and a catalog.xml file.

You use the component compiler to create the following kinds of assets:

Component libraries. 

Component libraries are SWC files that contain one or more components that are used by applications. SWC files also contain the namespace information that describe the contents of the SWC file. For more information about component libraries, see About SWC files.

Run-time shared libraries (RSLs). 

RSLs are external shared assets that can be separately downloaded and cached on the client. These shared assets are loaded by any number of applications at run time. For more information on RSLs, see Using Runtime Shared Libraries.

Themes. 

Themes are a combination of graphical and programmatic skins, and Cascading Style Sheets (CSS). You use themes to define the look and feel of a Flex application. For more information on themes, see Using Styles and Themes in Adobe Flex 3 Developer Guide.

You open the component compiler in the following ways:

Flex Builder 

Library Project compiler. 

Flex Builder uses the component compiler when you create a Library Project. (The application compiler is used for Flex Projects and ActionScript Projects). For more information, see Using the Flex Builder component compiler.

The compc command-line compiler. 

You open the compc compiler from the command line to create a SWC file. For more information, see Using the compc component compiler.

The component compiler has many of the same options as the application compilers, as described in About the application compiler options. The component compiler has additional options as described in About the component compiler options.

Like the application compiler, you can use the load-config option to point the component compiler to a configuration file, rather than specify command-line options or set the options in the Flex Library Compiler dialog box.

When you compile a SWC file, store the new file in a location that is not the same as the source files. If both sets of files are accessible by Flex when you compile your application, unexpected behavior can occur.

The SWC files that are produced by the component compilers do not require an HTML wrapper because they are used as themes, RSLs, or component libraries that are input to other compilers to create Flex applications. You never deploy a SWC file that users can request directly.

Using the Flex Builder component compiler

You use the component compiler in Flex Builder to create SWC files. You do this by setting up a Flex Library Project using the New Library Project command. You add MXML and ActionScript components, style sheets, SWF files, and other assets to the project.

To open the Flex Builder component compiler, select Project > Build Project for your Flex Library Project.

You edit the compiler settings by using the settings on the Project > Properties > Flex Library Compiler dialog box. Using the Additional Compiler Arguments field in this dialog box, you can set compiler options as if you were using the command-line compiler. For information about the syntax for setting options in the Flex Library Compiler dialog box, see About the command-line compilers.

You can set the value of some options using the GUI controls. To set the resource options in the Flex Library Build Path dialog box, select Project > Properties > Flex Library Build Path.

Flex Builder does not expose a default configuration file to set compiler options but you can create your own and pass it to the compiler with the load-config option. For more information on setting compiler options with configuration files, see About configuration files.

Using the compc component compiler

You use the compc command-line compiler to compile SWC files from MXML, ActionScript, and other source files such as style sheets, images, and SWF files.

You can open the compc compiler as a shell script and executable file for use on Windows and UNIX systems. It is in the flex_install_dir/bin directory in Flex SDK.

To use the compc compiler, you should understand how to pass options and use configuration files. For more information, see About the command-line compilers.

The syntax of the compc compiler is as follows:

compc [options] -include-classes class [...]

The default option for compc is include-classes. At least one of the "include-" options is required.

To see a list of supported options for compc, you can use the help list option, as the following example shows:

compc -help list

The compc compiler uses the default compiler settings in the flex-config.xml file. Like the application compiler, you can change these settings or use another custom configuration file. Unlike the application compiler, however, the component compiler does not support the use of default configuration files.

You cannot use the compc compiler to create a SWC file from a FLA file or other file created in the Adobe® Flash® authoring environment.

You can also open the compc compiler with the java command on the command line. For more information, see Invoking the command-line compilers with Java.