Java News from Saturday, December 18, 2004

Sun's posted the fifth snapshot release of Mustang, a.k.a Java 1.6, a.k.a Java 6. This is basically an early development release that includes source code. It's currently published only under the Java Research License. It's available on the usual Sun-supported platforms: Linux, Solaris, and Windows.

Tom Copeland has released PMD 2.1, an open source tool for automatically checking Java code for various classes of bugs. PMD scans Java source code and looks for potential problems including:

• Unused local variables
• Empty catch blocks
• Unused parameters
• Empty if statements
• Duplicate import statements
• Unused private methods
• Classes which could be Singletons
• Short/long variable and method names
• Importing sun classes
• Empty finalizers
• Empty static initializers
• Overloaded finalize methods
• Finalize does not call super.finalize()
• Dollar signs in identifiers
• Method with the same name as the enclosing class
• Explicit calls to finalize
• Empty statements
• "Suspicious" octal escapes
• "Suspicious" hash code method names
• Exceptions as flow control
• Catching NullPointerExceptions

This release makes various usability improvements and adds two new rules, AvoidProtectedFieldInFinalClass and SystemPrintln.