NumberUtils.java

/**
 * jetbrick-template
 * http://subchen.github.io/jetbrick-template/
 *
 * Copyright 2010-2014 Guoqiang Chen. All rights reserved.
 * Email: subchen@gmail.com
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package jetbrick.template.utils;

import java.text.DecimalFormat;

public final class NumberUtils {
    private static final String DEFAULT_NUMBER_FORMAT = "###,##0.00";

    public static String format(Number value, String format) {
        return value == null ? null : new DecimalFormat(format).format(value);
    }

    public static String format(Number value) {
        return format(value, DEFAULT_NUMBER_FORMAT);
    }

    public static int sum(int[] values) {
        if (values == null || values.length == 0) {
            return 0;
        }
        int sum = 0;
        for (int value : values) {
            sum += value;
        }
        return sum;
    }

    public static int avg(int[] values) {
        if (values == null || values.length == 0) {
            return 0;
        }
        return sum(values) / values.length;
    }

    public static int max(int[] values) {
        if (values == null || values.length == 0) {
            return 0;
        }
        int max = Integer.MIN_VALUE;
        for (int value : values) {
            if (value > max) {
                max = value;
            }
        }
        return max;
    }

    public static int min(int[] values) {
        if (values == null || values.length == 0) {
            return 0;
        }
        int min = Integer.MAX_VALUE;
        for (int value : values) {
            if (value < min) {
                min = value;
            }
        }
        return min;
    }
}