Thursday 29 April 2010

Miglayout DSL

Here's an embryonic DSL for MigLayout in Java.  Statically imported enums turn out to be a pretty handy alternative to Smalltalk or Erlang atoms.  Unfortunately I can't find the HTML syntax highlighter for Java.


import static MigBuilder.*;

Object mig = mig(size(BUTTON_WIDTH, BUTTON_HEIGHT), gapleft(LEFT_GAP), hidemode(zero), growx, growy);
        
String migconstraint = "w 11!, h 52!, gapleft 3, growx, growy";

enum MigBuilder {
  grow, growx, growy, push, gapleft;
 
  public static Object mig(Object...strings)
  {
    StringBuilder builder = new StringBuilder();
    for (Object object : strings)
    {
      if(object instanceof MigBuilder)
        builder.append(',');
     
      builder.append(String.valueOf(object));
    }
    return builder.toString();     
  }
 
  public static Object size(int width, int height)
  {
    return mig("w ", width, "!,h ", height, '!');
  }
 
  public static Object gapleft(int pixels)
  {
    return mig(gapleft, pixels);
  }
 
  public static Object hidemode(HideMode hidemode)
  {
    return mig("hidemode ", hidemode);
  }
}

Friday 9 April 2010

UML

I was reading this article about the supposed best use of UML diagrams during the course of a project, in particular, generating code from UML is useless.  I have to agree that it seems pointless, once the generated code is modified the UML diagram is no longer useful and can no longer be used to generate the source.  Maybe this has just be used in the wrong way.  UML could be used in the same way as a unit test.  Perhaps initially it could generate code but also assert that code sticks to the design, if not then this test would fail and the architects would be notified.  This would help keep the architects up to date on what the codebase looked like without constant peer reviews, keep the documentation up to date and give warning when the design needed to change.  I have a feeling this is already done by someone.