Pragmatic Programmer Issues – pietrowski.info

Sun is purchasing the intellectual property of CDC spec phone maker SavaJe. It may be very interesting phone war, we have a couple new big players such as apple and now sun. I think this year may be very interesting for mobile devices. Another point in this war is that Apple don’t support java on his Mac OS X. That means that we all have java 5 update 11 but Mac OS X has java 5 update 7. Now I must review My dreams about MacBook.

News in JDBC 4.0

A new JSR-221 specifies JDBC version 4. A list of changes is not so huge, there’s some minor changes. One of the major changes was addition XML data type support which is mapped to SQLXML java type. Another added data type is RowId interface, SQL ROWID is the fastest way to access data. Another nice enchantment is that you don’t have to call Class.forName and register driver to driver manager. Everything you must do is put JDBC driver into classpath.

There are many minor changes such as adding DatabaseMetaData, adding more methods such as createClob in Connection, free in Array and others, pleas refers to JDBC specification for details, but in my opinion the most change is introduction more implementation of ResultSet and better Exception Handling.

Our last seminar was abort scala language. I met with this language in December 2006 when I was prepared own seminary about java kingdom of languages. Martin Odersky makes experiment to create functional and object programming language. He chose java virtual machine as a compilation platform so scala has great library support.

One of very interesting feature from java perspective is patter matching (known from other functional languages SML, Heskell).

abstract class Tree
case class Sum(l: Tree, r: Tree) extends Tree
case class Var(n: String) extends Tree
case class Const(v: int) extends Tree

This snapshot is from scala tutorial. The case modifier makes from normal class a class with standard definition of getters for parameters, equals, hashCode, toString. Now through patter matching scala can evaluate Tree expression depends on the match to class Sum, Car, Const.

Scala has mixins, methods can have names like =, +, – etc., and true genericity , another interesting thin is xml included (maybe in jdk7) so we can define variable such as:

xml_data =

Last interesting fact is that scala allows you to use Actors to simple send and receive messages (Erlang style).

It’s very interesting language and of course we have even now web framework for it. It’s name is lift