Java

Regular Expression Replace Full Matches

See more Regular Expressions Examples

Demonstrates replacing the full matches of a regular expression.

Note: Chilkat uses PCRE2. See PCRE2 Regular Expressions
Also see: PCRE2 Performance

Java

import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    boolean success = false;

    success = false;

    String subject = "John Anders, +_+_+ Mary Robins $$$$";
    String pattern = "\\w+\\s+\\w+";

    CkStringBuilder sb = new CkStringBuilder();
    sb.Append(subject);

    CkJsonObject json = new CkJsonObject();
    json.put_EmitCompact(false);

    int timeoutMs = 2000;
    int numMatches = sb.RegexMatch(pattern,json,timeoutMs);
    if (numMatches < 0) {
        // Probably an error in the regular expression.
        // Suggestion: Use AI to help create and/or diagnose regular expressions.
        System.out.println(sb.lastErrorText());
        return;
        }

    // Examine the matches:
    System.out.println(json.emit());

    // {
    //   "match": [
    //     {
    //       "group": [
    //         {
    //           "cap": "John Anders",
    //           "idx": 0,
    //           "len": 11
    //         }
    //       ]
    //     },
    //     {
    //       "group": [
    //         {
    //           "cap": "Mary Robins",
    //           "idx": 19,
    //           "len": 11
    //         }
    //       ]
    //     }
    //   ]
    // }

    CkStringBuilder sbTemp = new CkStringBuilder();

    int i = 0;
    numMatches = json.SizeOfArray("match");
    while (i < numMatches) {

        json.put_I(i);

        // The full match is always in group 0.
        sbTemp.Clear();
        json.StringOfSb("match[i].group[0].cap",sbTemp);

        // Indicate that we wish to replace the full match with it's value converted to uppercase.
        sbTemp.ToUppercase();
        json.UpdateSb("match[i].group[0].rep",sbTemp);

        i = i+1;
        }

    // The JSON now has replacement strings:
    System.out.println(json.emit());

    // {
    //   "match": [
    //     {
    //       "group": [
    //         {
    //           "cap": "John Anders",
    //           "idx": 0,
    //           "len": 11,
    //           "rep": "JOHN ANDERS"
    //         }
    //       ]
    //     },
    //     {
    //       "group": [
    //         {
    //           "cap": "Mary Robins",
    //           "idx": 19,
    //           "len": 11,
    //           "rep": "MARY ROBINS"
    //         }
    //       ]
    //     }
    //   ]
    // }

    // Call RegexReplace to update the StringBuilder with the replacements.
    success = sb.RegexReplace(json);
    if (success == false) {
        System.out.println(sb.lastErrorText());
        return;
        }

    System.out.println("Result after doing replacements:");
    System.out.println(sb.getAsString());

    // Result after doing replacements:
    // JOHN ANDERS, +_+_+ MARY ROBINS $$$$
  }
}