Drop the symbol separator in the currency and percent re-parse

src/main/java/org/apache/commons/validator/routines/CurrencyValidator.java

@@ -59,6 +59,18 @@ public static BigDecimalValidator getInstance() {
         return VALIDATOR;
     }
 
+    /**
+     * Tests whether the character at the given position of a pattern sits next to the currency symbol.
+     *
+     * @param pattern The pattern being stripped of its currency symbol.
+     * @param index The position to test.
+     * @return {@code true} if the character borders the currency symbol.
+     */
+    private static boolean isNextToSymbol(final String pattern, final int index) {
+        return index > 0 && pattern.charAt(index - 1) == CURRENCY_SYMBOL
+                || index + 1 < pattern.length() && pattern.charAt(index + 1) == CURRENCY_SYMBOL;
+    }
+
     /**
      * Constructs a <em>strict</em> instance.
      */
@@ -106,8 +118,11 @@ protected Object parse(final String value, final Format formatter) {
         if (pattern.indexOf(CURRENCY_SYMBOL) >= 0) {
             final StringBuilder buffer = new StringBuilder(pattern.length());
             for (int i = 0; i < pattern.length(); i++) {
-                if (pattern.charAt(i) != CURRENCY_SYMBOL) {
-                    buffer.append(pattern.charAt(i));
+                final char chr = pattern.charAt(i);
+                // A locale that suffixes the symbol usually separates it from the number with a (non-breaking)
+                // space. That space belongs to the symbol, so dropping only the symbol would leave it mandatory.
+                if (chr != CURRENCY_SYMBOL && !(Character.isSpaceChar(chr) && isNextToSymbol(pattern, i))) {
+                    buffer.append(chr);
                 }
             }
             decimalFormat.applyPattern(buffer.toString());

src/main/java/org/apache/commons/validator/routines/PercentValidator.java

@@ -64,6 +64,18 @@ public static BigDecimalValidator getInstance() {
         return VALIDATOR;
     }
 
+    /**
+     * Tests whether the character at the given position of a pattern sits next to the percent symbol.
+     *
+     * @param pattern The pattern being stripped of its percent symbol.
+     * @param index The position to test.
+     * @return {@code true} if the character borders the percent symbol.
+     */
+    private static boolean isNextToSymbol(final String pattern, final int index) {
+        return index > 0 && pattern.charAt(index - 1) == PERCENT_SYMBOL
+                || index + 1 < pattern.length() && pattern.charAt(index + 1) == PERCENT_SYMBOL;
+    }
+
     /**
      * Constructs a <em>strict</em> instance.
      */
@@ -109,8 +121,11 @@ protected Object parse(final String value, final Format formatter) {
         if (pattern.indexOf(PERCENT_SYMBOL) >= 0) {
             final StringBuilder buffer = new StringBuilder(pattern.length());
             for (int i = 0; i < pattern.length(); i++) {
-                if (pattern.charAt(i) != PERCENT_SYMBOL) {
-                    buffer.append(pattern.charAt(i));
+                final char chr = pattern.charAt(i);
+                // A locale that suffixes the symbol usually separates it from the number with a (non-breaking)
+                // space. That space belongs to the symbol, so dropping only the symbol would leave it mandatory.
+                if (chr != PERCENT_SYMBOL && !(Character.isSpaceChar(chr) && isNextToSymbol(pattern, i))) {
+                    buffer.append(chr);
                 }
             }
             decimalFormat.applyPattern(buffer.toString());

src/test/java/org/apache/commons/validator/routines/CurrencyValidatorTest.java

@@ -38,6 +38,9 @@ class CurrencyValidatorTest {
 
     private static final char CURRENCY_SYMBOL = '\u00A4';
 
+    /** The character locales such as de-DE use between the number and a trailing currency symbol. */
+    private static final char NON_BREAKING_SPACE = '\u00A0';
+
     private String usDollar;
     private String ukPound;
 
@@ -176,6 +179,21 @@ void testPattern() {
         assertFalse(validator.isValid(ukPound + "1,234.567", pattern, Locale.US), "invalid symbol");
     }
 
+    /**
+     * Test currency values with a pattern that suffixes the symbol, which locales such as de-DE separate from the number with a non-breaking space. The symbol
+     * is optional, so its separator has to be optional too.
+     */
+    @Test
+    void testSuffixSymbolPattern() {
+        final BigDecimalValidator validator = CurrencyValidator.getInstance();
+        final String pattern = "#,##0.00" + NON_BREAKING_SPACE + CURRENCY_SYMBOL;
+        final BigDecimal expected = new BigDecimal("1234.56");
+
+        assertEquals(expected, validator.validate("1,234.56" + NON_BREAKING_SPACE + usDollar, pattern, Locale.US), "symbol");
+        assertEquals(expected, validator.validate("1,234.56", pattern, Locale.US), "no symbol");
+        assertNull(validator.validate("1,234.56" + NON_BREAKING_SPACE, pattern, Locale.US), "separator without symbol");
+    }
+
     /**
      * Test Valid currency values
      */

src/test/java/org/apache/commons/validator/routines/PercentValidatorTest.java

@@ -35,6 +35,11 @@
  */
 class PercentValidatorTest {
 
+    private static final char PERCENT_SYMBOL = '%';
+
+    /** The character locales such as fr-FR use between the number and a trailing percent symbol. */
+    private static final char NON_BREAKING_SPACE = '\u00A0';
+
     protected PercentValidator validator;
     private Locale originalLocale;
 
@@ -100,6 +105,21 @@ void testNumberRangeExactBound() {
         assertFalse(instance.minValue(new BigDecimal("5"), new BigDecimal("5.5")));
     }
 
+    /**
+     * Test percentage values with a pattern that suffixes the symbol, which locales such as fr-FR separate from the number with a non-breaking space. The
+     * symbol is optional, so its separator has to be optional too.
+     */
+    @Test
+    void testSuffixSymbolPattern() {
+        final BigDecimalValidator validator = PercentValidator.getInstance();
+        final String pattern = "#,##0" + NON_BREAKING_SPACE + PERCENT_SYMBOL;
+        final BigDecimal expected = new BigDecimal("0.12");
+
+        assertEquals(expected, validator.validate("12" + NON_BREAKING_SPACE + PERCENT_SYMBOL, pattern, Locale.US), "symbol");
+        assertEquals(expected, validator.validate("12", pattern, Locale.US), "no symbol");
+        assertNull(validator.validate("12" + NON_BREAKING_SPACE, pattern, Locale.US), "separator without symbol");
+    }
+
     /**
      * Test Valid percentage values
      */