The fourth programming project involves designing, writing andtesting a program that behaves like the Java command line compiler.Whenever we request that the Java compiler recompile a particularclass, it not only recompiles that class but every other class thatdepends upon it, directly or indirectly, and in a particular order.To make the determination about which classes need recompilation,the Java compiler maintains a directed graph of class dependencies.Any relationship in a UML class diagram of a Java program such asinheritance relationships, composition relationships andaggregations relationships indicate a class dependency. The mainclass P4GUI should create the Swing based GUI shown below:

The
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