From c8e61afdb89c58ea8ffaf04593da41ff0888d30e Mon Sep 17 00:00:00 2001
From: Piotr Kosmala <piotr.kosmala@ncdc.pl>
Date: Sat, 10 Feb 2018 15:19:36 +0100
Subject: [PATCH] LANG-1060: NumberUtils.isNumber assumes number starting with
 Zero is octal (closes #313)

---
 .../java/org/apache/commons/lang3/math/NumberUtils.java    | 2 +-
 .../org/apache/commons/lang3/math/NumberUtilsTest.java     | 7 +++++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/main/java/org/apache/commons/lang3/math/NumberUtils.java b/src/main/java/org/apache/commons/lang3/math/NumberUtils.java
index 5942db7f3..9428ba797 100644
--- a/src/main/java/org/apache/commons/lang3/math/NumberUtils.java
+++ b/src/main/java/org/apache/commons/lang3/math/NumberUtils.java
@@ -1407,7 +1407,7 @@ public class NumberUtils {
         boolean foundDigit = false;
         // deal with any possible sign up front
         final int start = chars[0] == '-' || chars[0] == '+' ? 1 : 0;
-        if (sz > start + 1 && chars[start] == '0') { // leading 0
+        if (sz > start + 1 && chars[start] == '0' && !StringUtils.contains(str, '.')) { // leading 0, skip if is a decimal number
             if (chars[start + 1] == 'x' || chars[start + 1] == 'X') { // leading 0x/0X
                 int i = start + 2;
                 if (i == sz) {
diff --git a/src/test/java/org/apache/commons/lang3/math/NumberUtilsTest.java b/src/test/java/org/apache/commons/lang3/math/NumberUtilsTest.java
index 20d87fe30..376a57916 100644
--- a/src/test/java/org/apache/commons/lang3/math/NumberUtilsTest.java
+++ b/src/test/java/org/apache/commons/lang3/math/NumberUtilsTest.java
@@ -1326,6 +1326,10 @@ public class NumberUtilsTest {
         compareIsNumberWithCreateNumber("-1234", true);
         compareIsNumberWithCreateNumber("-1234.5", true);
         compareIsNumberWithCreateNumber("-.12345", true);
+        compareIsNumberWithCreateNumber("-0001.12345", true);
+        compareIsNumberWithCreateNumber("-000.12345", true);
+        compareIsNumberWithCreateNumber("+00.12345", true);
+        compareIsNumberWithCreateNumber("+0002.12345", true);
         compareIsNumberWithCreateNumber("-1234E5", true);
         compareIsNumberWithCreateNumber("0", true);
         compareIsNumberWithCreateNumber("-0", true);
@@ -1342,6 +1346,7 @@ public class NumberUtilsTest {
         compareIsNumberWithCreateNumber(" ", false);
         compareIsNumberWithCreateNumber("\r\n\t", false);
         compareIsNumberWithCreateNumber("--2.3", false);
+
         compareIsNumberWithCreateNumber(".12.3", false);
         compareIsNumberWithCreateNumber("-123E", false);
         compareIsNumberWithCreateNumber("-123E+-212", false);
@@ -1352,6 +1357,8 @@ public class NumberUtilsTest {
         compareIsNumberWithCreateNumber("-0ABC123", false);
         compareIsNumberWithCreateNumber("123.4E-D", false);
         compareIsNumberWithCreateNumber("123.4ED", false);
+        compareIsNumberWithCreateNumber("+000E.12345", false);
+        compareIsNumberWithCreateNumber("-000E.12345", false);
         compareIsNumberWithCreateNumber("1234E5l", false);
         compareIsNumberWithCreateNumber("11a", false);
         compareIsNumberWithCreateNumber("1a", false);