Regex to replace word

**TechGate** · 11-02-2010

Hello,
I am Looking to replace an exact word in a string, but I have a little trouble. In fact I have the following string "param23 + 12 + param2"(Without the quotes) and I also have a Map with the value of my parameter. I would like to replace my param by their respective values. I can not find the regex that replaces me (in a replaceAll - requires Java 1.4) and param2 only param2.
Here is my code

Code:

 Public static String updateFormula(OriginalFormula String, Map replacementMap)
    {
        String nwfor = originalFormula;

        List ky = new ArrayList();
        ky.addAll(replacementMap.keySet());
 
        for (int i = 0; I <ky.size(); I + +)
        {
            if (ky.get(i) != null)
            {
                nwfor = nwfor.replaceAll(ky.get(i).function toString() {
    [native code]
}(), ReplacementMap.get(ky.get(i)).function toString() {
    [native code]
}());
            }
        }

        consoleLogger.debug("updateFormula (" + + OriginalFormula ") -> " + NewFormula);
 
        return nwfor;
    }

**Vodka** · 11-02-2010

Hello,
I am also trying a similar coding to perform the same task. Here is my code, if you have any ideas about it, or my code is wrong then please correct me.

Code:

 Public static String updateFormula(OriginalFormula String, Map replacementMap)
    {
        String str = originalFormula;

        Pattern p = null;
        Matcher m = null;
        
        List ky = new ArrayList();
        ky.addAll(replacementMap.keySet());
 
        for (int i = 0; I <ky.size(); I + +)
        {
            if (ky.get(i) != null)
            {
/ / NewFormula = str.replaceAll (ky.get (i). ToString (), replacementMap.get (ky.get (i)). ToString ());
                p = Pattern.compiles(ky.get(i).function toString() {
    [native code]
}());
                m = p.matcher(str);
                
                str = m.replaceAll(replacementMap.get(ky.get(i)).function toString() {
    [native code]
}());
            }
        }

        Pims.consoleLogger.debug("updateFormula (" + + OriginalFormula ") -> " + NewFormula);
 
        return str;
    }

**Linux-Us** · 11-02-2010

Hello,
Otherwise a small note before I begin, you create a ArrayList Temporary nothing much go directly keySet ().
Besides, let's just go the entrySet () which includes the pair key / value. As for your problem more precisely, here is a code that should work. Here is the code for it.

Code:

Public static String updateFormula(OriginalFormula String, Map replacementMap) {
		String str = originalFormula;

Iterator keyIterator = replacementMap.entrySet().iterator();
		while (keyIterator.hasNext()) {
			Map.Entry entry = (Map.Entry) keyIterator.next();
String key = "(?<=\\p (Punct) |\\p (Space }|^)" + Pattern.quote( entry.getKey().function toString() {
    [native code]
}() ) + "(?=\\p (Punct) |\\p (Space }|$)";
String value = entry.getValue().function toString() {
    [native code]
}();
str = str.replaceAll( key, value);
		}
		/ / consoleLogger.debug ( "updateFormula (" originalFormula + + ") ->" + str);
 
		return str;
	}

I have changed it, please have a look.

**NetworkeR** · 11-02-2010

Hello,
Adding to the above post Pattern.quote () is only available Java 5.0. But you can find an equivalent 1.4 here, How to prevent regular expressions to interpret a substring? This enables you to avoid a possible special characters in your keys are not "break" your regexp When the elements surrounding the key, they can add constraints on the elements surrounding the chain (without taking into account the replacement)

Code:

    * "(?<=\ \ p (pn) | \ \ p (sp) | ^)" :
      "(?<=)"Lets you specify the above term. Here we allow only \ \ p (pn) | \ \ p (sp) | ^, Respectively: a punctuation, a whitespace or the start of the string.

    * "(?=\ \ p (pn) | \ \ p (sp) | $)" Do the same thing, but for the following characters:
      "(?=)"To specify the elements that follow the term. Here we allow only \ \ p (pn) | \ \ p (sp) | $, Respectively: a punctuation, a whitespace or the end of the chain.

**WinDoWLoCuS** · 11-02-2010

Hello,
If you need an example that is depicting the above, then here it is

Code:

String s = "param3 + param22 + 12 + 8param1 + 0 + param2";

Map m = new HashMap();
m.could("param2", "5415");

System.out.System.out.println(s);
System.out.System.out.println(updateFormula(s, m));

Hope you understand things and your problem is solved.

**SoftWore** · 11-02-2010

Hello,
I have tried it and this works very well, I think even you should have a try to it. Regarding the iterators confess not be too familiar with them, where the ArrayList. For performance issue cons keep an instance of Map.Entry in the loop is not more resources than declare the variable before the loop entry and simply change this value in the while? If you need help regarding the api in java that is the classes and the method used in java, then you can visit the official site of java for more information on the API.