The JaxMe JavaSource framework

This is a framework for generating Java sources. It is based on an abstraction of the Java sources. For instance, there is an object called JavaSource. This object can have embedded instances of JavaMethod or JavaField, it can have inner classes, constructors, and so on. You get the idea. Compared to a basic approach of just using Writer.write(String), the framework has the obvious disadvantage of additional complexity and overhead. However, it also has some advantages:

1. Your sources become more readable and simpler, for example by automatically importing external classes, if required.
2. Postprocessing the generated sources is much easier. You get the chance to generate sources in multiple steps, or in a pipeline like this:

   Handle the case of a single element

   ---->

   Handle the case of a Collection

3. Your generator is much more controlled by the compiler and well suited for refactoring. This is best illustrated by looking at the following example:

         JavaMethod jm;
         jm.addLine(MyClass.class, " myInstance = new ", MyClass.class, "();");
       

   This example assumes the existance of a class "MyClass". The compiler verifies the existance and a refactoring module might, for example, rename this class.
4. It has a lot of nice shortcuts, for example:

         addTry();
         addLine("int i = Integer.parseInt(s);");
         addCatch(NumberFormatException.class);
         addThrowNew(IllegalArgumentException.class,
                     JavaSource.getQuoted("Invalid integer argument: "), " + s");
         addEndTry();
       

Table of Contents

• History and license of the JavaSource framework
• Using the JavaSourceFactory
• Basic design patterns implemented with the JaxMe JavaSource framework:
  • Proxy objects, that implement given interfaces by delegating method calls to another implementation
  • Multiple inheritance, implemented with the proxy generator
  • Typesafe enumerations
  • Proxy chains (also known as delegator pattern)
  • A version generator
• Writing methods
  
  • Throwing exceptions
  • if .. else if .. else .. blocks
  • try .. catch .. block
• Code Optimizations
  
  • The DirectAccessible interface
• Placeholders
• Working with SQL
  
  • Creating a schema
  • Creating a table
  • Creating an INSERT statement
  • Creating a SELECT statement
  • Creating an UPDATE statement
  • Creating a DELETE statement
  • Creating one or more CREATE TABLE statements
  • Vendor specific extensions
• Joining the project or getting support
• Java API
• Changes

Links

• The JaxMe home page
• DrMem, a simple heap profiler