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javaregexstringsplittokenize

String regex is not working to split words in closed parenthesis

I am working a string regex to split the below string 

String input = "( Customer.browse == \"Car Loan\" ) AND ( Campaign.period BETWEEN 2400 AND 600 ) "
            + "AND ( Customer.eligibity == TRUE ) AND ( Campaign.campaign_name == \"Browse To Start\") "
            + "AND ( Customer.application_started == \"Car Loan\" ) AND ( Time.currenttime BETWEEN 800 AND 2000 ) "
            + "THEN ( Notification.message == SUPPRESS)";

My string tokenizer class is as below 

import java.util.ArrayList;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

    public class StringRegexClass {

        public ArrayList<String> stringTokenizer(String str) {

            ArrayList<String> tokenList = new ArrayList<String>();
            Pattern pattern = Pattern.compile("[(\")]|\\w+.\\w+.\\w+|\\w+.\\w+|==");
            Matcher matcher = pattern.matcher(str);
            while (matcher.find()) {
                tokenList.add(matcher.group());
            }
            return (tokenList);
        }
    }

And I am getting output as below when I am passing the string to the above class

enter image description here

I want to split the strings in parenthesis ( Time.currenttime BETWEEN 800 AND 2000 ) and ( Campaign.period BETWEEN 2400 AND 600 ) as below

enter image description here

I tried different ways none of it worked can you please suggest what changes I need to make to my regex expression to make it work

Solution

  • I would recommend you capture the quoted string in full.

    You need to escape the .

    You can use the following regex, but be aware that it will silently skip anything it doesn't recognize:

    [()]|"[^"]*"|\w+(?:\.\w+)?|==

    In Java 4+:

    public static List<String> stringTokenizer2(String str) {
    List<String> tokenList = new ArrayList<>();
    Pattern pattern = Pattern.compile("[()]|\"[^\"]*\"|\\w+(?:\\.\\w+)?|==");
    for (Matcher matcher = pattern.matcher(str); matcher.find(); )
        tokenList.add(matcher.group());
    return tokenList;
}

    In Java 9+:

    public static List<String> stringTokenizer(String str) {
    return Pattern.compile("[()]|\"[^\"]*\"|\\w+(?:\\.\\w+)?|==").matcher(str)
            .results().map(MatchResult::group).collect(Collectors.toList());
}

    Test (Java 8)

    String input = "( Customer.browse == \"Car Loan\" ) AND ( Campaign.period BETWEEN 2400 AND 600 ) AND ( Customer.eligibity == TRUE ) AND ( Campaign.campaign_name == \"Browse To Start\") AND ( Customer.application_started == \"Car Loan\" ) AND ( Time.currenttime BETWEEN 800 AND 2000 ) THEN ( Notification.message == SUPPRESS)";
for (String token : stringTokenizer(input))
    System.out.println(token);

    Output

    (
Customer.browse
==
"Car Loan"
)
AND
(
Campaign.period
BETWEEN
2400
AND
600
)
AND
(
Customer.eligibity
==
TRUE
)
AND
(
Campaign.campaign_name
==
"Browse To Start"
)
AND
(
Customer.application_started
==
"Car Loan"
)
AND
(
Time.currenttime
BETWEEN
800
AND
2000
)
THEN
(
Notification.message
==
SUPPRESS
)