improved tests

json-path-assert/src/test/java/com/jayway/jsonassert/JsonAssertTest.java

@@ -1,5 +1,6 @@
 package com.jayway.jsonassert;
 
+import org.hamcrest.Matchers;
 import org.junit.Test;
 
 import static com.jayway.jsonassert.JsonAssert.*;
@@ -91,4 +92,14 @@ public class JsonAssertTest {
                 .assertThat("$.store.book[0].title", equalTo("Sayings of the Century"));
     }
 
+    @Test
+    public void no_hit_returns_null() throws Exception {
+        with(JSON).assertThat("$.store.book[1000].title", Matchers.<Object>nullValue());
+    }
+
+    @Test
+    public void invalid_path() throws Exception {
+        with(JSON).assertThat("$.store.book[*].fooBar", emptyCollection());
+    }
+
 }

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

@@ -172,9 +172,12 @@ public class JsonPath {
             }
         }
 
-        if (result.size() != 1) {
+        if (result.size() > 1) {
             throw new RuntimeException(format("Expected one result when reading path: %s  but was: ", jsonPath, result.size()));
         }
+        else if (result.isEmpty()){
+            return null;
+        }
         return (T) result.get(0);
     }