Using Pattern and Matcher Classes - Java Regular Expressions

Java examples for Regular Expressions:Match

  1. HOME
  2. Java
  3. Regular Expressions
  4. Match

Description

Using Pattern and Matcher Classes

Demo Code

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

public class Main {
  public static void main(String[] args) {
    String regex = "[abc]@.";

    String source = "cric@mypkg.com is a valid email address";
    Main.findPattern(regex, source);/*ww  w.ja  v a 2  s  .c o  m*/

    source = "asdf@mypkg.com is invalid";
    Main.findPattern(regex, source);

    source = "a@asdf@fdsa@u";
    Main.findPattern(regex, source);

    source = "There is an @ sign here";
    Main.findPattern(regex, source);
  }

  public static void findPattern(String regex, String source) {
    // Compile regex into a Pattern object
    Pattern p = Pattern.compile(regex);

    // Get a Matcher object
    Matcher m = p.matcher(source);

    boolean found = false ;

    // Print regex and source text
    System.out.println("\nRegex:" + regex);
    System.out.println("Text:" + source);

    // Perform find
    while (m.find()) {
      System.out.println("Matched Text:" + m.group() + ", Start:" + m.start() + ", " + 
                         "End:" + m.end());

      // We found at least one match. Set the found flag to true
      found = true;
    }

    if (!found) {
      // We did not find any match
      System.out.println("No match found");
    }
  }
}

Related Tutorials