Regex Pattern/Matcher to match a exact word

Question

I am trying to build a regex pattern using the Pattern and Matcher classes in salesforce to find a exact match of a word . For eg. the word hot should be found in the 1st 3 string but not in the 4th one.

hot in here

It's hot

how hot is it

[email protected] --- > should not match.

I tried with the below code but cannot get it to work. Any help is appreciated.

String strRegEx = '\\bhot\\b';
String str = ' how hot is it';

Pattern MyPattern = Pattern.compile(strRegEx);
Matcher MyMatcher = MyPattern.matcher(str);
Boolean result = MyMatcher.matches();

Answer 1

Found the issue. It was not with the Regex pattern but with the Apex code.

 String strRegEx = '\\bhot\\b';
 String str = ' how hot is it';

 Pattern MyPattern = Pattern.compile(strRegEx);
 Matcher MyMatcher = MyPattern.matcher(str);
 Boolean result = MyMatcher.find();

Answer 2

Try this regex

String strResEx = '\\b(hot)\\b';

We need double \ as \b is special character.

Hope this helps.

Answer 3

Pattern kiwiSaverPattern = Pattern.compile('[K]{1}[0-9]{6,7}');
Pattern nzrtSaverPattern = Pattern.compile('\\b[0-9]{5,6}\\b');
Matcher kiwiSaverMatcher;
Matcher nzrtMatcher;

String strSubject = 'This is a test K5535934 test subject K55345545 K12345 395020 20504 with NZRT Number in it 857389';
kiwiSaverMatcher = kiwiSaverPattern.matcher(strSubject);
nzrtMatcher = nzrtSaverPattern.matcher(strSubject);
Integer cnt = 0;
while(nzrtMatcher.find()){

    System.debug('========== Occurrence ' + nzrtMatcher.group(0));
    cnt++;   
}
System.debug('========= cnt ' + cnt);

Integer cntr = 0;
while(kiwiSaverMatcher.find()){

    System.debug('========== Occurrence ' + kiwiSaverMatcher.group(0));
    cntr++;   
}
System.debug('========= cntr ' + cntr);