fix issue #425 and add test cases.

json-path/src/main/java/com/jayway/jsonpath/JsonPath.java

@@ -112,7 +112,15 @@ public class JsonPath {
     public static boolean isPathDefinite(String path) {
         return compile(path).isDefinite();
     }
-
+    public static boolean isPathValid(String json,String path){
+        try{
+            JsonPath.parse(json).read(path);
+            return true;
+        }
+        catch (PathNotFoundException e){
+            return false;
+        }
+    }
 
     /**
      * Checks if a path points to a single item or if it potentially returns multiple items

json-path/src/test/java/com/jayway/jsonpath/Issue_425.java

@@ -0,0 +1,25 @@
+package com.jayway.jsonpath;
+
+
+import org.junit.Test;
+
+/**
+ * test for issue 425
+ */
+public class Issue_425 {
+
+    @Test
+    public void testCheckPathFunction() {
+        Boolean valid= JsonPath.isPathValid("{\n" +
+                "   \"a\": [1,2,3],\n" +
+                "   \"b\": [4,5,6]\n" +
+                "}", "$.c");
+        assert (valid.equals(Boolean.FALSE));
+        valid= JsonPath.isPathValid("{\n" +
+                "   \"a\": [1,2,3],\n" +
+                "   \"b\": [4,5,6]\n" +
+                "}", "$.a");
+        assert (valid.equals(Boolean.TRUE));
+    }
+}
+