package com.opencsv.bean.validators;
   
   import com.opencsv.bean.BeanField;
   import com.opencsv.exceptions.CsvValidationException;
   
   import java.util.ResourceBundle;
   
   /**
    * <p>This is a validator that, due to the addition of the parameter, allows the validation of multiple different types
   * of input.  The paramString must be a valid regular expression.  The MustMatchRegularExpression validator will
   * the {@link String#matches(String)} method on the string to be converted and the regular expression string and if
   * the two do not match then a {@link CsvValidationException} will be thrown.</p>
   * <p>Because this is validating the string <em>before</em> it is parsed/converted, the capture settings
   * of the string must be taken into account.</p>
   * <p>Examples:</p>
   * <pre>
   *     // The String that becomes id must be a number with three to six digits.
   *     &#64;PreAssignmentValidator(validator = MustMatchRegexExpression.class, paramString = "^[0-9]{3,6}$")
   *     &#64;CsvBindByName(column = "id")
   *     private int beanId;
   *
   *     // The String that becomes bigNumber must be a number with seven to ten digits.
   *     // The String for this field is after the word "value: " in the field.
   *     &#64;PreAssignmentValidator(validator = MustMatchRegexExpression.class, paramString = "^[A-Za-z ]*value: [0-9]{7,10}$")
   *     &#64;CsvBindByName(column = "big number", capture = "^[A-Za-z ]*value: (.*)$", format = "value: %s")
   *     private long bigNumber;
   * </pre>
   */
  public class MustMatchRegexExpression implements StringValidator {
      private String regex = "";
  
      /**
       * Default constructor.
       */
      public MustMatchRegexExpression() {
          this.regex = "";
      }
  
      @Override
      public boolean isValid(String value) {
          if (regex.isEmpty()) {
              return true;
          }
          return value.matches(regex);
      }
  
      @Override
      public void validate(String value, BeanField field) throws CsvValidationException {
          if (!isValid(value)) {
              throw new CsvValidationException(String.format(ResourceBundle.getBundle("mustMatchRegex", field.getErrorLocale())
                      .getString("validator.regex.mismatch"), field.getField().getName(), value, regex));
          }
      }
  
      @Override
      public void setParameterString(String value) {
          if (value != null && !value.isEmpty()) {
              regex = value;
          }
      }
  }