com.ancientprogramming.fixedformat4j.format.impl.AbstractDecimalFormatter.java Source code

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Here is the source code for com.ancientprogramming.fixedformat4j.format.impl.AbstractDecimalFormatter.java

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/*
 * Copyright 2004 the original author or authors.
 *
 * 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.ancientprogramming.fixedformat4j.format.impl;

import com.ancientprogramming.fixedformat4j.format.FormatInstructions;
import org.apache.commons.lang.StringUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import java.math.BigDecimal;
import java.math.RoundingMode;
import java.text.DecimalFormat;

/**
 * Base class for formatting decimal data
 *
 * @author Jacob von Eyben - http://www.ancientprogramming.com
 * @since 1.0.0
 */
public abstract class AbstractDecimalFormatter<T extends Number> extends AbstractNumberFormatter<T> {

    private static final Log LOG = LogFactory.getLog(AbstractDecimalFormatter.class);

    public String asString(T obj, FormatInstructions instructions) {
        BigDecimal roundedValue = null;
        int decimals = instructions.getFixedFormatDecimalData().getDecimals();
        if (obj != null) {
            BigDecimal value = obj instanceof BigDecimal ? (BigDecimal) obj : BigDecimal.valueOf(obj.doubleValue());

            RoundingMode roundingMode = instructions.getFixedFormatDecimalData().getRoundingMode();

            roundedValue = value.setScale(decimals, roundingMode);

            if (LOG.isDebugEnabled()) {
                LOG.debug("Value before rounding = '" + value + "', value after rounding = '" + roundedValue
                        + "', decimals = " + decimals + ", rounding mode = " + roundingMode);
            }
        }

        DecimalFormat formatter = new DecimalFormat();
        formatter.setDecimalSeparatorAlwaysShown(true);
        formatter.setMaximumFractionDigits(decimals);

        char decimalSeparator = formatter.getDecimalFormatSymbols().getDecimalSeparator();
        char groupingSeparator = formatter.getDecimalFormatSymbols().getGroupingSeparator();
        String zeroString = "0" + decimalSeparator + "0";

        String rawString = roundedValue != null ? formatter.format(roundedValue) : zeroString;
        if (LOG.isDebugEnabled()) {
            LOG.debug("rawString: " + rawString + " - G[" + groupingSeparator + "] D[" + decimalSeparator + "]");
        }
        rawString = rawString.replaceAll("\\" + groupingSeparator, "");
        boolean useDecimalDelimiter = instructions.getFixedFormatDecimalData().isUseDecimalDelimiter();

        String beforeDelimiter = rawString.substring(0, rawString.indexOf(decimalSeparator));
        String afterDelimiter = rawString.substring(rawString.indexOf(decimalSeparator) + 1, rawString.length());
        if (LOG.isDebugEnabled()) {
            LOG.debug("beforeDelimiter[" + beforeDelimiter + "], afterDelimiter[" + afterDelimiter + "]");
        }

        //trim decimals
        afterDelimiter = StringUtils.substring(afterDelimiter, 0, decimals);
        afterDelimiter = StringUtils.rightPad(afterDelimiter, decimals, '0');

        String delimiter = useDecimalDelimiter ? "" + instructions.getFixedFormatDecimalData().getDecimalDelimiter()
                : "";
        String result = beforeDelimiter + delimiter + afterDelimiter;
        if (LOG.isDebugEnabled()) {
            LOG.debug("result[" + result + "]");
        }
        return result;
    }

    protected String getStringToConvert(String string, FormatInstructions instructions) {
        String toConvert;
        boolean useDecimalDelimiter = instructions.getFixedFormatDecimalData().isUseDecimalDelimiter();
        if (useDecimalDelimiter) {
            char delimiter = instructions.getFixedFormatDecimalData().getDecimalDelimiter();
            toConvert = string.replace(delimiter, '.'); //convert to normal delimiter
        } else {
            int decimals = instructions.getFixedFormatDecimalData().getDecimals();
            if (decimals > 0 && string.length() >= decimals) {
                String beforeDelimiter = string.substring(0, string.length() - decimals);
                String afterDelimiter = string.substring(string.length() - decimals, string.length());
                toConvert = beforeDelimiter + '.' + afterDelimiter;
            } else {
                toConvert = string;
            }

        }
        return toConvert;
    }
}