Fixed JAVAMONEY-94, Removed magic Strings for formatting.

Author: atsticks

src/main/java/org/javamoney/moneta/format/AmountFormatParams.java

@@ -0,0 +1,48 @@
+/**
+ * Copyright (c) 2012, 2014, Credit Suisse (Anatole Tresch), Werner Keil and others by the @author tag.
+ *
+ * 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 org.javamoney.moneta.format;
+
+/**
+ * Class holding constants for passing additional parameters to {@link javax.money.MonetaryAmountFactoryQuery}
+ * instances for configuring {@link javax.money.format.MonetaryAmountFormat} instances to be accessed.
+ */
+public final class AmountFormatParams {
+
+    /**
+     * Non instantiatable class.
+     */
+    private AmountFormatParams() {
+    }
+
+    /**
+     * Allows to pass a pattern as defined by {@link java.text.DecimalFormat}.
+     */
+    public static final String PATTERN = "pattern";
+
+    /**
+     * Allows to define the grouping sizes of the number groups as {@code int[]}, hereby starting from the decimal point.
+     * So {@code 2, 2, 3} will format the number {@code 1234567890} as {@code 123.456.78.90}, assuming '.' as the only
+     * grouping char. The grouping chars used can be similarly adapted/combined, see #GROUPING_GROUPING_SEPARATORS.
+     */
+    public static final String GROUPING_SIZES = "groupingSizes";
+
+    /**
+     * Allows to define the grouping characters of a number groups as {@code char[]}, hereby starting from the decimal point.
+     * So {@code '''',':','.'} will format the number {@code 1234567890} as {@code 1'234:567.890}, assuming 3 as the only
+     * grouping size. The grouping sizes used can be similarly adapted/combined, see #GROUPING_SIZES.
+     */
+    public static final String GROUPING_GROUPING_SEPARATORS = "groupingSeparators";
+}

src/main/java/org/javamoney/moneta/format/internal/AmountNumberToken.java

@@ -15,6 +15,8 @@
  */
 package org.javamoney.moneta.format.internal;
 
+import org.javamoney.moneta.format.AmountFormatParams;
+
 import java.io.IOException;
 import java.math.BigDecimal;
 import java.text.DecimalFormat;
@@ -86,8 +88,8 @@ public String getNumberPattern() {
     public void print(Appendable appendable, MonetaryAmount amount)
             throws IOException {
         int digits = amount.getCurrency().getDefaultFractionDigits();
-        if (amountFormatContext.get("groupingSizes", int[].class) == null ||
-                amountFormatContext.get("groupingSizes", int[].class).length == 0) {
+        if (amountFormatContext.get(AmountFormatParams.GROUPING_SIZES, int[].class) == null ||
+                amountFormatContext.get(AmountFormatParams.GROUPING_SIZES, int[].class).length == 0) {
             appendable.append(this.formatFormat.format(amount.getNumber()
                     .numberValue(BigDecimal.class)));
             return;
@@ -101,12 +103,12 @@ public void print(Appendable appendable, MonetaryAmount amount)
             appendable.append(preformattedValue);
         } else {
             if (Objects.isNull(numberGroup)) {
-                char[] groupChars = amountFormatContext.get("groupingSeparators", char[].class);
+                char[] groupChars = amountFormatContext.get(AmountFormatParams.GROUPING_GROUPING_SEPARATORS, char[].class);
                 if (groupChars == null || groupChars.length == 0) {
                     groupChars = new char[]{this.formatFormat
                             .getDecimalFormatSymbols().getGroupingSeparator()};
                 }
-                int[] groupSizes = amountFormatContext.get("groupingSizes", int[].class);
+                int[] groupSizes = amountFormatContext.get(AmountFormatParams.GROUPING_SIZES, int[].class);
                 if (groupSizes == null) {
                     groupSizes = new int[0];
                 }