Using the more approtiate PathNotFoundException if old key in rename map was not found.

json-path/src/main/java/com/jayway/jsonpath/internal/PathRef.java

@@ -1,9 +1,6 @@
 package com.jayway.jsonpath.internal;
 
-import com.jayway.jsonpath.Configuration;
-import com.jayway.jsonpath.InvalidModificationException;
-import com.jayway.jsonpath.InvalidPathException;
-import com.jayway.jsonpath.JsonPath;
+import com.jayway.jsonpath.*;
 import com.jayway.jsonpath.spi.json.JsonProvider;
 
 import java.util.Collection;
@@ -55,7 +52,7 @@ public abstract class PathRef implements Comparable<PathRef>  {
     protected void renameInMap(Object targetMap, String oldKeyName, String newKeyName, Configuration configuration){
         if(configuration.jsonProvider().isMap(targetMap)){
             if(configuration.jsonProvider().getMapValue(targetMap, oldKeyName) == JsonProvider.UNDEFINED){
-                throw new InvalidPathException("Key "+oldKeyName+" not found in map!");
+                throw new PathNotFoundException("No results for Key "+oldKeyName+" found in map!");
             }
             configuration.jsonProvider().setProperty(targetMap, newKeyName, configuration.jsonProvider().getMapValue(targetMap, oldKeyName));
             configuration.jsonProvider().removeProperty(targetMap, oldKeyName);

json-path/src/test/java/com/jayway/jsonpath/WriteTest.java

@@ -246,7 +246,7 @@ public class WriteTest extends BaseTest {
         parse(JSON_DOCUMENT).renameKey("$.store.book[*]['author', 'category']", "old-key", "new-key");
     }
 
-    @Test(expected = InvalidPathException.class)
+    @Test(expected = PathNotFoundException.class)
     public void non_existent_key_rename_not_allowed(){
         Object o = parse(JSON_DOCUMENT).renameKey("$", "fake", "new-fake").json();
     }