Class Panel is part of the awt package API and can be packaged as a bean. Recall the fully qualified name of class Panel is java.awt.Panel, and API packages come with the Java Development Kit(JDK) in a jar file called src.jar .
Use the WinZip application to open the src.jar file. Find the archive of the Panel.java . This file has the path src\java\awt associated with it, and those directories will be created. The package of class Panel is java.awt; therefore, the class Panel will only be recognized by java applications from a perspective where the java directory is a subdirectory, i.e. from the src directory.
Warning: The folks at Sun did not create text source files (.java) for the windows environment. Consequently, the return is seen as a funky character. Microsoft uses both a carriage return and line feed for a new line. Don't ask me what order because I don't know at the moment. Unix uses one of the two. Yes, I don't recall which one. Determining that is left as an exercise to the reader.
Warning: Know what the path and class path variables do before trying to run javac, jar, and the beanbox. Hey, another reader exercise!
From the src directory at a DOS command line we can run the jar utility where the class path is set to
at least the current directory (or the directory specification of the src directory). So to make a jar
file we can type:
But a bean must be packaged properly for a beanbox application. We forgot two important points:
The source file is not required, the Jave byte code is. (.class files)
A manifest is required to identify the Panel.class as a bean. I will leave using the javac utility
to make a Panel.class file in the same directory as the Panel.java location an exercise again.
The next page in this presentation will discuss the manifest.