Pass the property key along via the exception.

git-svn-id: https://samskivert.googlecode.com/svn/trunk@2973 6335cc39-0255-0410-8fd6-9bcaacd3b74c

src/main/java/com/samskivert/util/MissingPropertyException.java

@@ -27,8 +27,16 @@ package com.samskivert.util;
  */
 public class MissingPropertyException extends RuntimeException
 {
-    public MissingPropertyException (String message)
+    public MissingPropertyException (String key, String message)
     {
         super(message);
+        _key = key;
     }
+
+    public String getKey ()
+    {
+        return _key;
+    }
+
+    protected String _key;
 }

src/main/java/com/samskivert/util/PropertiesUtil.java

@@ -238,7 +238,7 @@ public class PropertiesUtil
     {
         String value = props.getProperty(key);
         if (StringUtil.isBlank(value)) {
-            throw new MissingPropertyException(missingMessage);
+            throw new MissingPropertyException(key, missingMessage);
         }
         return value;
     }