Hi! Can anyone expalain difference between .sqlj and .java files?
Best regards!
A:
Wikipedia explains this.
A .java file is a normal Java source code file. An .sqlj file is a Java source code file with embedded SQL statements. You have to pass .sqlj source files through a preprocessor to make normal .java files from them, which you can then compile with a standard Java compiler.
Jesper
2010-05-17 14:48:48
but if I use Select statement in .java file then i also use SQL statements in .java. Why I need .sqlj?
Debuger
2010-05-18 08:49:33
You cannot add a `SELECT` statement directly in a Java source file. You'd have to make a `Statement` object, pass the query as a string etc. SQLJ makes it so that you can put SQL statements directly in your source file, without a lot of boilerplate code. The preprocessor will add the boilerplate code for you. Look at the Wikipedia page, it shows an example.
Jesper
2010-05-18 11:50:47
Can You please say, where in real life we use SQLJ classes and why? In real applicationsor so on?Best regards, Kristaps
Debuger
2010-05-18 13:47:15
I don't think that in practice there are many people who use SQLJ; I've never encountered it myself in more than 10 years of programming in Java. It's not a widely used way to use SQL from Java. There are other technologies, such as plain JDBC, or ORM frameworks such as Hibernate, which are much more common.
Jesper
2010-05-19 06:55:30
+1
A:
From the wikipedia article:
Whereas JDBC provides an API, SQLJ consists of a language extension. Thus programs containing SQLJ must be run through a preprocessor (the SQLJ translator) before they can be compiled.
aioobe
2010-05-17 14:48:53