8154295: Currency iso code is int and hence looses the preceeding zero

Reviewed-by: naoto, okutsu, peytoia

jdk/src/java.base/share/classes/java/util/Currency.java

@@ -545,6 +545,33 @@ public final class Currency implements Serializable {
         return numericCode;
     }
 
+    /**
+     * Returns the 3 digit ISO 4217 numeric code of this currency as a {@code String}.
+     * Unlike {@link getNumericCode()}, which returns the numeric code as {@code int},
+     * this method always returns the numeric code as a 3 digit string.
+     * e.g. a numeric value of 32 would be returned as "032",
+     * and a numeric value of 6 would be returned as "006".
+     *
+     * @return the 3 digit ISO 4217 numeric code of this currency as a {@code String}
+     * @since 9
+     */
+    public String getNumericCodeAsString() {
+        /* numeric code could be returned as a 3 digit string simply by using
+           String.format("%03d",numericCode); which uses regex to parse the format,
+           "%03d" in this case. Parsing a regex gives an extra performance overhead,
+           so String.format() approach is avoided in this scenario.
+        */
+        if (numericCode < 100) {
+            StringBuilder sb = new StringBuilder();
+            sb.append('0');
+            if (numericCode < 10) {
+                sb.append('0');
+            }
+            return sb.append(numericCode).toString();
+        }
+        return String.valueOf(numericCode);
+    }
+
     /**
      * Gets the name that is suitable for displaying this currency for
      * the default {@link Locale.Category#DISPLAY DISPLAY} locale.
@@ -788,3 +815,4 @@ public final class Currency implements Serializable {
         }
     }
 }
+

jdk/test/java/util/Currency/Bug8154295.java

@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+/*
+ * @test
+ * @bug 8154295
+ * @summary Check getNumericCodeAsString() method which returns numeric code as a 3 digit String.
+ */
+
+import java.util.Currency;
+
+public class Bug8154295 {
+
+    public static void main(String[] args) {
+
+        String numericCode = Currency.getInstance("AFA").getNumericCodeAsString();
+        if (!numericCode.equals("004")) { //should return "004" (a 3 digit string)
+           throw new RuntimeException("[Expected 004, "
+                + "found "+numericCode+" for AFA]");
+        }
+
+        numericCode = Currency.getInstance("AUD").getNumericCodeAsString();
+        if (!numericCode.equals("036")) { //should return "036" (a 3 digit string)
+            throw new RuntimeException("[Expected 036, "
+                + "found "+numericCode+" for AUD]");
+        }
+
+        numericCode = Currency.getInstance("USD").getNumericCodeAsString();
+        if (!numericCode.equals("840")) {// should return "840" (a 3 digit string)
+            throw new RuntimeException("[Expected 840, "
+                + "found "+numericCode+" for USD]");
+        }
+
+    }
+
+}