LANG-1102: Make logic for comparing OS versions in SystemUtils smarter

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/lang/trunk@1669750 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 27 insertions, 1 deletions

diff --git a/src/main/java/org/apache/commons/lang3/SystemUtils.java b/src/main/java/org/apache/commons/lang3/SystemUtils.java
index 6508ddcbf..ba99a4ae0 100644
--- a/src/main/java/org/apache/commons/lang3/SystemUtils.java
+++ b/src/main/java/org/apache/commons/lang3/SystemUtils.java
@@ -1448,7 +1448,7 @@ public class SystemUtils {
         if (osName == null || osVersion == null) {
             return false;
         }
-        return isOSNameMatch(osName, osNamePrefix) && osVersion.startsWith(osVersionPrefix);
+        return isOSNameMatch(osName, osNamePrefix) && isOSVersionMatch(osVersion, osVersionPrefix);
     }
 
     /**
@@ -1467,6 +1467,32 @@ public class SystemUtils {
         }
         return osName.startsWith(osNamePrefix);
     }
+    
+    /**
+     * Decides if the operating system version matches.
+     * <p>
+     * This method is package private instead of private to support unit test invocation.
+     * </p>
+     *
+     * @param osVersion the actual OS version
+     * @param osVersionPrefix the prefix for the expected OS version
+     * @return true if matches, or false if not or can't determine
+     */
+    static boolean isOSVersionMatch(final String osVersion, final String osVersionPrefix) {
+        if (StringUtils.isEmpty(osVersion)) {
+            return false;
+        }
+        // Compare parts of the version string instead of using String.startsWith(String) because otherwise
+        // osVersionPrefix 10.1 would also match osVersion 10.10
+        String[] versionPrefixParts = osVersionPrefix.split("\\.");
+        String[] versionParts = osVersion.split("\\.");
+        for (int i = 0; i < Math.min(versionPrefixParts.length, versionParts.length); i++) {
+            if (!versionPrefixParts[i].equals(versionParts[i])) {
+                return false;
+            }
+        }
+        return true;
+    }
 
     // -----------------------------------------------------------------------
     /**