DMDirc-Util/src/com/dmdirc/util/validators/NumericalValidator.java

/*
 * Copyright (c) 2006-2010 Chris Smith, Shane Mc Cormack, Gregory Holmes
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

package com.dmdirc.util.validators;

/**
 * Validates that a number is within certain bounds.
 *
 * @author chris
 */
public class NumericalValidator implements Validator<String> {

    /** The minimum value for this number. */
    protected final int min;

    /** The maximum value for this number. */
    protected final int max;

    /**
     * Creates a new numerical validator with the specified bounds.
     *
     * @param min The minimum value for the number, or -1 for unlimited.
     * @param max The maximum value for the number, or -1 for unlimited.
     */
    public NumericalValidator(final int min, final int max) {
        this.max = max == -1 ? Integer.MAX_VALUE : max;
        this.min = min == -1 ? Integer.MIN_VALUE : min;
        if (this.min > this.max) {
            throw new IllegalArgumentException("min must be less than max.");
        }
    }

    /**
     * Retrieves the maximum value that this validator will allow.
     *
     * @return This validator's maximum value
     */
    public int getMax() {
        return max;
    }

    /**
     * Retrieves the minimum value that this validator will allow.
     *
     * @return This validator's minimum value
     */
    public int getMin() {
        return min;
    }

    /** {@inheritDoc} */
    @Override
    public ValidationResponse validate(final String object) {
        int intv;

        try {
            intv = Integer.parseInt(object);
        } catch (NumberFormatException ex) {
            return new ValidationResponse("Must be a valid number");
        }

        if (intv < min) {
            return new ValidationResponse("Must be at least " + min);
        } else if (intv > max) {
            return new ValidationResponse("Must be at most " + max);
        } else {
            return new ValidationResponse();
        }
    }

}