Validator: Regular expression functionality

[Jani Laakso]

Jukka has created following validator with his customer project

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

import org.millstone.base.data.Validator;

/**
 * Validates a string against a given regular expression.
 * 
 * @author Oy IT Mill Ltd
 * 
 */
public class RegularExpressionValidator implements Validator {

    private boolean allowNull;

    private String message;

    private String reqularExpression;

    private Pattern pattern;

    /**
     * 
     * @param message
     *            to put on exception if value is not valid.
     * @param regularExpression
     *            that is compiled to Pattern just before validation.
     * @param allowNull,
     *            if <code>true</code> the null or empty value is valid.
     */
    public RegularExpressionValidator(String message, String regularExpression, boolean allowNull) {
        this.allowNull = allowNull;
        this.message = message;
        if (regularExpression == null)
            throw new IllegalArgumentException("Regular expression must not be null.");
        this.reqularExpression = regularExpression;
    }

    /**
     * 
     * @param message
     *            to put on exception if value is not valid.
     * @param pattern
     * @param allowNull,
     *            if <code>true</code> the null or empty value is valid.
     */
    public RegularExpressionValidator(String message, Pattern pattern, boolean allowNull) {
        this.allowNull = allowNull;

        if (pattern == null)
            throw new IllegalArgumentException("Pattern must not be null.");
        this.pattern = pattern;
        this.message = message;
    }

    public boolean isValid(Object value) {

        String str = value.toString();
        if (allowNull && (str == null || "".equals(str.toString())))
            return true;

        // Pattern compilation is postponed to here
        if (this.pattern == null)
            pattern = Pattern.compile(this.reqularExpression);
        Matcher matcher = pattern.matcher((CharSequence) str);
        return matcher.matches();
    }

    public void validate(Object value) throws InvalidValueException {
        if (!isValid(value))
            throw new InvalidValueException(message);
    }
}

[Jani Laakso]

Milestone 4.2.0-rc deleted