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diff --git a/src/main/java/org/apache/commons/math/fraction/FractionFormat.java b/src/main/java/org/apache/commons/math/fraction/FractionFormat.java
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+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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 org.apache.commons.math.fraction;
+
+import java.text.FieldPosition;
+import java.text.NumberFormat;
+import java.text.ParseException;
+import java.text.ParsePosition;
+import java.util.Locale;
+
+import org.apache.commons.math.ConvergenceException;
+import org.apache.commons.math.MathRuntimeException;
+import org.apache.commons.math.exception.util.LocalizedFormats;
+
+/**
+ * Formats a Fraction number in proper format or improper format.  The number
+ * format for each of the whole number, numerator and, denominator can be
+ * configured.
+ *
+ * @since 1.1
+ * @version $Revision: 983921 $ $Date: 2010-08-10 12:46:06 +0200 (mar. 10 août 2010) $
+ */
+public class FractionFormat extends AbstractFormat {
+
+    /** Serializable version identifier */
+    private static final long serialVersionUID = 3008655719530972611L;
+
+    /**
+     * Create an improper formatting instance with the default number format
+     * for the numerator and denominator.
+     */
+    public FractionFormat() {
+    }
+
+    /**
+     * Create an improper formatting instance with a custom number format for
+     * both the numerator and denominator.
+     * @param format the custom format for both the numerator and denominator.
+     */
+    public FractionFormat(final NumberFormat format) {
+        super(format);
+    }
+
+    /**
+     * Create an improper formatting instance with a custom number format for
+     * the numerator and a custom number format for the denominator.
+     * @param numeratorFormat the custom format for the numerator.
+     * @param denominatorFormat the custom format for the denominator.
+     */
+    public FractionFormat(final NumberFormat numeratorFormat,
+                          final NumberFormat denominatorFormat) {
+        super(numeratorFormat, denominatorFormat);
+    }
+
+    /**
+     * Get the set of locales for which complex formats are available.  This
+     * is the same set as the {@link NumberFormat} set.
+     * @return available complex format locales.
+     */
+    public static Locale[] getAvailableLocales() {
+        return NumberFormat.getAvailableLocales();
+    }
+
+    /**
+     * This static method calls formatFraction() on a default instance of
+     * FractionFormat.
+     *
+     * @param f Fraction object to format
+     * @return A formatted fraction in proper form.
+     */
+    public static String formatFraction(Fraction f) {
+        return getImproperInstance().format(f);
+    }
+
+    /**
+     * Returns the default complex format for the current locale.
+     * @return the default complex format.
+     */
+    public static FractionFormat getImproperInstance() {
+        return getImproperInstance(Locale.getDefault());
+    }
+
+    /**
+     * Returns the default complex format for the given locale.
+     * @param locale the specific locale used by the format.
+     * @return the complex format specific to the given locale.
+     */
+    public static FractionFormat getImproperInstance(final Locale locale) {
+        return new FractionFormat(getDefaultNumberFormat(locale));
+    }
+
+    /**
+     * Returns the default complex format for the current locale.
+     * @return the default complex format.
+     */
+    public static FractionFormat getProperInstance() {
+        return getProperInstance(Locale.getDefault());
+    }
+
+    /**
+     * Returns the default complex format for the given locale.
+     * @param locale the specific locale used by the format.
+     * @return the complex format specific to the given locale.
+     */
+    public static FractionFormat getProperInstance(final Locale locale) {
+        return new ProperFractionFormat(getDefaultNumberFormat(locale));
+    }
+
+    /**
+     * Create a default number format.  The default number format is based on
+     * {@link NumberFormat#getNumberInstance(java.util.Locale)} with the only
+     * customizing is the maximum number of fraction digits, which is set to 0.
+     * @return the default number format.
+     */
+    protected static NumberFormat getDefaultNumberFormat() {
+        return getDefaultNumberFormat(Locale.getDefault());
+    }
+
+    /**
+     * Formats a {@link Fraction} object to produce a string.  The fraction is
+     * output in improper format.
+     *
+     * @param fraction the object to format.
+     * @param toAppendTo where the text is to be appended
+     * @param pos On input: an alignment field, if desired. On output: the
+     *            offsets of the alignment field
+     * @return the value passed in as toAppendTo.
+     */
+    public StringBuffer format(final Fraction fraction,
+                               final StringBuffer toAppendTo, final FieldPosition pos) {
+
+        pos.setBeginIndex(0);
+        pos.setEndIndex(0);
+
+        getNumeratorFormat().format(fraction.getNumerator(), toAppendTo, pos);
+        toAppendTo.append(" / ");
+        getDenominatorFormat().format(fraction.getDenominator(), toAppendTo,
+            pos);
+
+        return toAppendTo;
+    }
+
+    /**
+     * Formats an object and appends the result to a StringBuffer. <code>obj</code> must be either a
+     * {@link Fraction} object or a {@link Number} object.  Any other type of
+     * object will result in an {@link IllegalArgumentException} being thrown.
+     *
+     * @param obj the object to format.
+     * @param toAppendTo where the text is to be appended
+     * @param pos On input: an alignment field, if desired. On output: the
+     *            offsets of the alignment field
+     * @return the value passed in as toAppendTo.
+     * @see java.text.Format#format(java.lang.Object, java.lang.StringBuffer, java.text.FieldPosition)
+     * @throws IllegalArgumentException is <code>obj</code> is not a valid type.
+     */
+    @Override
+    public StringBuffer format(final Object obj,
+                               final StringBuffer toAppendTo, final FieldPosition pos) {
+        StringBuffer ret = null;
+
+        if (obj instanceof Fraction) {
+            ret = format((Fraction) obj, toAppendTo, pos);
+        } else if (obj instanceof Number) {
+            try {
+                ret = format(new Fraction(((Number) obj).doubleValue()),
+                             toAppendTo, pos);
+            } catch (ConvergenceException ex) {
+                throw MathRuntimeException.createIllegalArgumentException(
+                    LocalizedFormats.CANNOT_CONVERT_OBJECT_TO_FRACTION,
+                    ex.getLocalizedMessage());
+            }
+        } else {
+            throw MathRuntimeException.createIllegalArgumentException(
+                LocalizedFormats.CANNOT_FORMAT_OBJECT_TO_FRACTION);
+        }
+
+        return ret;
+    }
+
+    /**
+     * Parses a string to produce a {@link Fraction} object.
+     * @param source the string to parse
+     * @return the parsed {@link Fraction} object.
+     * @exception ParseException if the beginning of the specified string
+     *            cannot be parsed.
+     */
+    @Override
+    public Fraction parse(final String source) throws ParseException {
+        final ParsePosition parsePosition = new ParsePosition(0);
+        final Fraction result = parse(source, parsePosition);
+        if (parsePosition.getIndex() == 0) {
+            throw MathRuntimeException.createParseException(
+                    parsePosition.getErrorIndex(),
+                    LocalizedFormats.UNPARSEABLE_FRACTION_NUMBER, source);
+        }
+        return result;
+    }
+
+    /**
+     * Parses a string to produce a {@link Fraction} object.  This method
+     * expects the string to be formatted as an improper fraction.
+     * @param source the string to parse
+     * @param pos input/ouput parsing parameter.
+     * @return the parsed {@link Fraction} object.
+     */
+    @Override
+    public Fraction parse(final String source, final ParsePosition pos) {
+        final int initialIndex = pos.getIndex();
+
+        // parse whitespace
+        parseAndIgnoreWhitespace(source, pos);
+
+        // parse numerator
+        final Number num = getNumeratorFormat().parse(source, pos);
+        if (num == null) {
+            // invalid integer number
+            // set index back to initial, error index should already be set
+            // character examined.
+            pos.setIndex(initialIndex);
+            return null;
+        }
+
+        // parse '/'
+        final int startIndex = pos.getIndex();
+        final char c = parseNextCharacter(source, pos);
+        switch (c) {
+        case 0 :
+            // no '/'
+            // return num as a fraction
+            return new Fraction(num.intValue(), 1);
+        case '/' :
+            // found '/', continue parsing denominator
+            break;
+        default :
+            // invalid '/'
+            // set index back to initial, error index should be the last
+            // character examined.
+            pos.setIndex(initialIndex);
+            pos.setErrorIndex(startIndex);
+            return null;
+        }
+
+        // parse whitespace
+        parseAndIgnoreWhitespace(source, pos);
+
+        // parse denominator
+        final Number den = getDenominatorFormat().parse(source, pos);
+        if (den == null) {
+            // invalid integer number
+            // set index back to initial, error index should already be set
+            // character examined.
+            pos.setIndex(initialIndex);
+            return null;
+        }
+
+        return new Fraction(num.intValue(), den.intValue());
+    }
+
+}