Gosling on Computing

CowboyRobot writes "ACM Queue has Eric Allman (creator of Sendmail) interviewing James Gosling (creator of Java) and the conversation covers many aspects of computing today, including the state of security, comparisons of languages and OSs, and the future of virtual machines. 'At the lowest level, you have to know that the boundaries around the piece of software are completely known and contained. So, for example, in Java, you can't go outside the bounds of an array. Ever. Period. Turning off array subscripting is not an option.'"

Gosling, Java? Hmmm.....

[Cyberax]

I lost all my respect to Gosling after a clumsy attempt to add generics to Java.

The right way to add generics to Java is a radical modification of JVM (Java Virtual Machine), but Sun didn't want to it. So they made an attempt to add generics to Java language without touching JVM. The result of this attempt is a complex scheme of name mangling (just like C++), and some unnecessary overhead. And such implementation _still_ requires some JVM changes and is incompatible with old JVMs. So now we have an ugly generics in Java and Java 5.0 (rebranded J2SE 1.5) incompatible with previous versions.

No Generics until 2006-2007 ??

[fforw]

Generics are non-existent to me. They won't be anywhere around until 2006-2007.

what are you talking about? the 1.5 release is already at "beta 2". So we will have a release version in autumn. Netbeans will reach it's beta for the 4.0 release soon, so there will be a matching, open-source IDE, too.

And all that before even 2005.

Re:No Generics until 2006-2007 ??

[Cyberax]

No. This is just a FUD.

.NET bytecodes has a well-known "verifiable subset" which can be automatically verified to be correct just like Java bytecode. CLR can be configured to reject non-safe code in some domains and accept it in another domains. For example, you can configure CLR to behave just like an applet sandbox for downloaded applications.

I repeat, Java bytecode is just a subset of IL. So you can do in .NET everything you can do in Java.

Re:Gosling, Java? Hmmm.....

[Cyberax]

Look at Retroweaver [sourceforge.net]. This is a project aimed to make Java 1.5 features work on previous JVMs (by weaving bytecode). They have a nice explanation why JDK 1.5 is incompatible with 1.4 somewhere on their site.

Re:JVM and virtual servers

[HappyClown]

Agreed this is indeed a problem, JVMs can be quite memory hungry. However there are several ways to address this. First of all, it's possible to have a single application server instance host multiple web applications. In fact, this is half the point of having an application server in the first place! Sure there's extra effort involved in getting the security and other configuration right, but it will save you gobs and gobs of memory.

Additionally, Sun will be providing new functionality in J2SE 1.6 (6.0?), due out in beta this year, to allow JVM resources to be shared across separate instances of the JVM.

Take a look at http://research.sun.com/projects/barcelona/papers/ oopsla00.pdf [sun.com] to see how Sun plan on addressing this.