Flash, Ant and lots of regular expression replaces - ant

Question

I have a flash project which, for optimization purposes, has to have constant references replaced with literals during release build.
There are hundreds of constants which I want to replace. All of them are stored in single file, in this format:
FILE: Constants.as
public static const CONST_1 :uint = 0;
public static const CONST_LOLO :int = -1;
public static const CONST_WHEE :Number = 2.55;
public static const OTHER_CONST :String = "La string!";
public static const ITSAMEMARIO :String = "O, HAI!";
public static const MAGE_WALL :uint = 15;
I figure I could do it manually, like that:
<replaceregexp match="CONST_1" replace="0">
<fileset dir="${project.sourcePath}" includes="**/*.as" />
</replaceregexp>
<replaceregexp match="CONST_LOLO" replace="-1">
<fileset dir="${project.sourcePath}" includes="**/*.as" />
</replaceregexp>
And so on, for all the other variables. The problem is twofold - first of all, it is quite a lot of work. But the bigger problem is, that these constants can change and I'd have to remember to do the change in two places.
Generally I am using Ant (which I just started to learn too) to accomplish this task, but if you think there is a better way, I am all ears. There are two solutions I can think of, none of which I know how to execute:
Write some smarty-pants piece of Ant code which would parse this constants file and happily do the replaces keeping everything in memory.
Make the task first parse the Constants.as, output a new Ant script, which then will be executed by the first task.
I am using Flash Builder 4.5 for all my Ant needs.
EDIT:
Some clarification. In the project I am using Constants, for example LEVEL_WIDTH. All of these constants are declared in the aforementioned Constants.as. Now what I want is to replace all of the instances of these constants in the whole project with their actual value. So such line:
return (x >= 0 && x < Constants.LEVEL_WIDTH);
will be replaced by:
return (x >= 0 && x < 20);

Answer 1

OK this is not the easiest thing to do with ant. First you need to know what you can change. This means all the names of your constants as well as the corresponding values. Are the constant names unique? If yes this sounds like a map structure to me. Then you need to regexreplace all your source files which contain one or more of these variables so that every constant is replaced with the actual value. This is not what ant is designed for but you can do it with a script def.
I would do this with java like this :
Store all constant/values into a map (if the constants are unique) else use a different structure.
Sample code :
<project name="test" default="build">
<property name="constants" value="constants.txt"/>
<scriptdef name="replaceConstants" language="java">
<attribute name="constants" />
<attribute name="srcFile" />
<![CDATA[
import java.util.*;
import java.util.regex.*;
ArrayList constantNameList = new ArrayList();
ArrayList constantValueList = new ArrayList();
var constantFile = attributes.get("constants");
Pattern regex = Pattern.compile("(?<=const)\\s+(\\b\\w+\\b).*?=\\s*(.*?)\\s*;");
Matcher regexMatcher = regex.matcher(constantFile);
while (regexMatcher.find()) {
constantNameList.add(regexMatcher.group(1));
constantValueList.add(regexMatcher.group(2));
}
for(int i = 0; i < constantNameList.size(); ++i)
{
//debugging
System.out.print("key : ");
System.out.print(constantNameList.get(i));
System.out.print(" value : ");
System.out.println(constantValueList.get(i));
//do the actual replacement here
}
]]>
</scriptdef>
<target name="build">
<loadfile property="constants.file" srcFile="${constants}"/>
<loadfile property="source.file" srcFile="sourceFile.txt"/>
<echo message="${constants.file}"/>
<replaceConstants constants="${constants.file}" srcFile="${source.file}"/>
</target>
</project>
You will need java 1.6 or later to run this as well as http://www.java2s.com/Code/Jar/ABC/bsh-2.0b5.jar.htm
This jar to run it.
Output :
[replaceConstants] key : CONST_1 value : 0
[replaceConstants] key : CONST_LOLO value : -1
[replaceConstants] key : CONST_WHEE value : 2.55
[replaceConstants] key : OTHER_CONST value : "La string!"
[replaceConstants] key : ITSAMEMARIO value : "O, HAI!"
[replaceConstants] key : MAGE_WALL value : 15
So what I did is stored all the constant names/value into two arrays. You need to iterate through the arrays and regex replace for each of your source files. The whole thing can be a macrodef which you can call multiple times.