com.sunchenbin.store.feilong.core.text.NumberFormatUtil.java Source code

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Here is the source code for com.sunchenbin.store.feilong.core.text.NumberFormatUtil.java

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/*
 * Copyright (C) 2008 feilong
 *
 * 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 com.sunchenbin.store.feilong.core.text;

import java.math.RoundingMode;
import java.text.ChoiceFormat;
import java.text.DecimalFormat;
import java.text.Format;
import java.text.NumberFormat;

import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.sunchenbin.store.feilong.core.lang.NumberPattern;

/**
 * {@link NumberFormat}?,?????.
 * 
 * <p>
 * ? {@link ChoiceFormat}, {@link DecimalFormat}.<br>
 * ?:<span style="color:red">{@link DecimalFormat}?? </span>,??. (?JAVA API )
 * </p>
 * 
 * @author feilong
 * @version 1.0.2 2012-3-27 ?1:39:53
 * @see Format
 * @see NumberFormat
 * @see DecimalFormat
 * @see NumberPattern
 * @since 1.0.2
 */
public final class NumberFormatUtil {

    /** The Constant LOGGER. */
    private static final Logger LOGGER = LoggerFactory.getLogger(NumberFormatUtil.class);

    /** Don't let anyone instantiate this class. */
    private NumberFormatUtil() {
        //AssertionError?. ?????. ???.
        //see Effective Java 2nd
        throw new AssertionError("No " + getClass().getName() + " instances for you!");
    }

    /**
     *  {@link Number}  numberPattern?.
     * 
     * <p>
     *  {@link java.math.RoundingMode#HALF_UP}
     * </p>
     *
     * @param value
     *            the value
     * @param numberPattern
     *            the pattern {@link NumberPattern}
     * @return  null
     * @see NumberPattern
     * @see DecimalFormat
     * @see RoundingMode#HALF_UP
     */
    public static String format(Number value, String numberPattern) {
        // ?, DecimalFormat RoundingMode.HALF_EVEN
        RoundingMode roundingMode = RoundingMode.HALF_UP;
        return format(value, numberPattern, roundingMode);
    }

    /**
     *  {@link Number}  {@link RoundingMode} numberPattern?.
     *
     * @param value
     *            the value
     * @param numberPattern
     *            the pattern {@link NumberPattern}
     * @param roundingMode
     *            ?{@link RoundingMode}
     * @return  null
     * @see NumberPattern
     * @see DecimalFormat
     * @see <a href="../util/NumberUtil.html#RoundingMode">JAVA 8??</a>
     */
    public static String format(Number value, String numberPattern, RoundingMode roundingMode) {
        if (null == value) {
            throw new NullPointerException("the value is null or empty!");
        }

        if (null == numberPattern) {
            throw new NullPointerException("the numberPattern is null or empty!");
        }
        try {
            // applyPattern(pattern, false)
            DecimalFormat decimalFormat = new DecimalFormat(numberPattern);

            // ? RoundingMode.HALF_EVEN
            // ?,?.?,?.??,?,??.???1?,???.
            // 1.15>1.2 1.25>1.2
            if (null != roundingMode) {
                decimalFormat.setRoundingMode(roundingMode);
            }
            String format = decimalFormat.format(value);
            if (LOGGER.isDebugEnabled()) {
                LOGGER.debug("value:[{}], pattern:[{}],return:[{}],decimalFormat.toLocalizedPattern():[{}]", value,
                        numberPattern, format, decimalFormat.toLocalizedPattern()//?? Format ????. 
                );
            }
            return format;
        } catch (Exception e) {
            Object[] objects = { e.getMessage(), value, numberPattern };
            LOGGER.error("{},value:[{}],pattern:[{}]", objects);
            LOGGER.error(e.getClass().getName(), e);
        }
        return StringUtils.EMPTY;
    }
}