Java™ Application Development on Linux - Dator

PrefacexxiiiFREE SOFTWARE AND JAVAGNU/Linux 2 is Free Software. It is Open Source. I don’t even want to startthe debate on what each term means and which one is “right.” One of the twoauthors of this book is a Free Software advocate, and the other is of a purelylaissez-faire attitude towards the question (we won’t tell you which, althoughwe invite you to guess). But even with a deliberate decision to cease-fire, thequestion remains: Is Java Open Source or Free Software?The answer is mixed. Neither Sun’s nor IBM’s Java implementations areOpen Source or Free Software. You may download and use them for free, butyou do not have the source code to them, nor do you have the right to makemodifications to them. 3 This book will cover the GNU Compiler for Java,which compiles Java source code to native machine code. The GNU Compilerfor Java (gcj) is both Open Source and Free Software. It is, however, supportingdiffering levels of the Java APIs (some packages are current, some are back at1.1.x levels) and does not fully support the AWT or Swing GUIs.However, none of this means that you cannot write your own Java programsand release them under a Free Software or Open Source license. So youcan certainly develop Free Software in Java. Staunch Free Software partisans(such as Richard Stallman and the Free Software Foundation) would questionthe wisdom of doing so. Their argument would be that a Free Software productthat depends on non-Free tools isn’t really Free Software, since to compile, use,or modify it, you need to make use of a proprietary tool.There is more than one effort to produce a Free Software Java runtimeimplementation. None of them is “ready for prime time.” It would, in ouropinion, be a very good thing for Sun to release their SDK and Java VirtualMachine as Free Software. But so far, they have steadily resisted calls to do so.2. This is the only time we will refer to it as “GNU/Linux.” See Section 7.3 for the story ofwhy GNU/Linux is the preferred name of some. We understand Stallman and the FSF’s position,but “Linux” is much easier on the eyes and ears than “GNU/Linux.” And that, not principle,is how names and words go into the language. For better or for worse, “Linux” is thename of the operating system.3. As we write this, a very public discussion is taking place between Sun, IBM, and Eric Raymond,founder of the Open Source Initiative, about opening Java under some sort of opensource license. At this time, no one knows how this will turn out, but it is possible that Javawill be Free Software in the future.