import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Example {
public static void main(String[] args) {
final String regex = "\\b(34[0-9]{2}[ -])([0-9]{6}[ -])[0-9]{5}\\b|\\b34[0-9]{13}\\b|\\b(37[0-9]{2}[ -])([0-9]{6}[ -])[0-9]{5}\\b|\\b37[0-9]{13}\\b";
final String string = "American Express\n\n"
+ "Requirements: American Express cards start with the number 34 or 37 and have 15 digits. Pattern is 4-6-5 when having spaces or dashes.\n\n"
+ "Pattern Parts:\n"
+ "Starts with number 34 and 15 length:\n"
+ "1) \\b(34[0-9]{2}[ -])([0-9]{6}[ -])[0-9]{5}\\b|\\b34[0-9]{13}\\b \n\n"
+ "Starts with number 37 and 15 length:\n"
+ "2) \\b(37[0-9]{2}[ -])([0-9]{6}[ -])[0-9]{5}\\b|\\b37[0-9]{13}\\b\n\n"
+ "Combining 1-2 to form one pattern:\n"
+ "\\b(34[0-9]{2}[ -])([0-9]{6}[ -])[0-9]{5}\\b|\\b34[0-9]{13}\\b|\\b(37[0-9]{2}[ -])([0-9]{6}[ -])[0-9]{5}\\b|\\b37[0-9]{13}\\b\n\n\n"
+ "Test Cases:\n"
+ "Positive (Should fire):\n"
+ "15 length, no space, start with 34 Here is the cc: 342312341234123 Thanks.\n"
+ "15 length, dashes, start with 34 3423-123456-12345 \n"
+ "15 length, spaces, start with 34 3423 123456 12345 \n\n"
+ "15 length, no space, start with 37 372112341234123\n"
+ "15 length, dashes, start with 37 3721-123456-12345\n"
+ "15 length, spaces, start with 37 3721 123456 12345\n\n"
+ "Embedded in sentence with space:\n"
+ "15 length, no space, start with 34 Here is the cc: 342312341234112\n"
+ "15 length, dashes, start with 34 Here is the cc: 3423-123456-12345\n"
+ "15 length, spaces, start with 34 Here is the cc: 3423 123456 12345\n\n"
+ "15 length, no space, start with 37 Here is the cc: 372112341234123\n"
+ "15 length, dashes, start with 37 Here is the cc: 3721-123456-12345\n"
+ "15 length, spaces, start with 37 Here is the cc: 3721 123456 12345\n\n"
+ "15 length, no space, start with 34 Credit Card#:342312341234112\n"
+ "15 length, dashes, start with 34 Credit Card#:3423-123456-12345\n"
+ "15 length, spaces, start with 34 Credit Card#:3423 123456 12345\n\n"
+ "15 length, no space, start with 37 Credit Card#:372112341234123\n"
+ "15 length, dashes, start with 37 Credit Card#:3721-123456-12345\n"
+ "15 length, spaces, start with 37 Credit Card#:3721 123456 12345\n\n"
+ "Negative (Should Not Fire):\n"
+ "15 length, no space, not start with 34 352312341234112\n"
+ "15 length, dashes, not start with 34 3523-123456-12345\n"
+ "15 length, spaces, not start with 34 3523 123456 12345\n\n"
+ "15 length, no space, not start with 37 362112341234123\n"
+ "15 length, dashes, not start with 37 3621-123456-12345\n"
+ "15 length, spaces, not start with 37 3621 123456 12345\n\n"
+ "15 length, no space, start with 34, embedded Credit Card Number342312341234112\n"
+ "15 length, dashes, start with 34, malformed 3423-1234-1234-112\n\n"
+ "15 length num matching pattern but embedded User ID: 000000342312341234112000000";
final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE);
final Matcher matcher = pattern.matcher(string);
while (matcher.find()) {
System.out.println("Full match: " + matcher.group(0));
for (int i = 1; i <= matcher.groupCount(); i++) {
System.out.println("Group " + i + ": " + matcher.group(i));
}
}
}
}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html