Java™ Application Development on Linux - Dator

122Chapter 5The Sun Microsystems Java Software <strong>Development</strong> KitThe class invoked must be findable on either the bootstrap or userspecifiedclasspath.5.4.2 java OptionsJust as the Java compiler, the runtime program, java, takes a number of command-lineoptions. Here are the most commonly used ones:-classpath or -cpSets the runtime classpath. Overrides any value in the CLASSPATHenvironment variable.-Dproperty=valueAllows a system property to be set on the command line.-jarSpecifies that the first nonoption command-line argument is not a Javaclass name, but the name of a JAR file. The JAR file must have aMain-Class: specification in its MANIFEST (see Section 5.11). Themain() method of the class named by the JAR’s MANIFEST Main-Class:specification will be called as if that class had been named on the commandline, rather than the JAR file. This is commonly used in shell scripts andbatch files that accompany Java applications distributed in single.jar files.There are several other command-line options that are less commonlyused. We will cover some of them in later chapters when their use will makemore sense. Of course, full documentation on all options for this command isin the Sun Java SDK <strong>Development</strong> Tools documentation.5.5COMPLETE, UP-TO-DATE PROGRAM DOCUMENTATION MADE EASYOne of Java’s most useful features is javadoc, a command that (by default)produces comprehensive HTML program documentation directly from theprogram source. Since it works from the source, it can be automated, and youmay be certain that the documentation is up-to-date. It takes much of thedocumentation burden off of programmers and permits new programmers tojoin a project and rapidly come up to speed because there is comprehensivedocumentation in a standard format. The javadoc tool produces HTML