From dc8e25cbe93579037affa9339c9d780a0148d9ff Mon Sep 17 00:00:00 2001
From: Manolo Carrasco <manolo@apache.org>
Date: Mon, 13 Feb 2012 08:08:08 +0000
Subject: [PATCH] Throw a NullPointerException when casting null to Js objects.
 Fixes issue_122

---
 .../com/google/gwt/query/client/Properties.java     |  9 ++-------
 .../com/google/gwt/query/client/js/JsCache.java     | 13 ++++++++++++-
 .../google/gwt/query/client/GQueryCoreTestGwt.java  |  7 +++++++
 3 files changed, 21 insertions(+), 8 deletions(-)

diff --git a/gwtquery-core/src/main/java/com/google/gwt/query/client/Properties.java b/gwtquery-core/src/main/java/com/google/gwt/query/client/Properties.java
index 6842e311..8b2793ff 100644
--- a/gwtquery-core/src/main/java/com/google/gwt/query/client/Properties.java
+++ b/gwtquery-core/src/main/java/com/google/gwt/query/client/Properties.java
@@ -15,6 +15,7 @@
  */
 package com.google.gwt.query.client;
 
+import com.google.gwt.core.client.GWT;
 import com.google.gwt.core.client.JavaScriptObject;
 import com.google.gwt.core.client.JsArrayMixed;
 import com.google.gwt.query.client.js.JsCache;
@@ -137,10 +138,6 @@ public class Properties extends JavaScriptObject {
   }
   
   public final String toJsonString() {
-    // In dev-mode a null object casted to JavascriptObject does not throw a NPE
-    // e.g: System.out.println(((Properties)null).toJsonString());
-    if (this == null) return "null";
-    
     String ret = "";
     for (String k : keys()){
       String ky = k.matches("\\d+") ? k : "\"" + k + "\"";
@@ -171,9 +168,6 @@ public class Properties extends JavaScriptObject {
   }
   
   public final String toQueryString() {
-    // In dev-mode a null object casted to JavascriptObject does not throw a NPE
-    if (this == null) return "null";
-    
     String ret = "";
     for (String k : keys()) {
       ret += ret.isEmpty() ? "" : "&";
@@ -206,4 +200,5 @@ public class Properties extends JavaScriptObject {
   public final boolean isEmpty(){
     return c().length() == 0;
   }
+
 }
diff --git a/gwtquery-core/src/main/java/com/google/gwt/query/client/js/JsCache.java b/gwtquery-core/src/main/java/com/google/gwt/query/client/js/JsCache.java
index bf64308d..ba7242a9 100644
--- a/gwtquery-core/src/main/java/com/google/gwt/query/client/js/JsCache.java
+++ b/gwtquery-core/src/main/java/com/google/gwt/query/client/js/JsCache.java
@@ -15,6 +15,7 @@
  */
 package com.google.gwt.query.client.js;
 
+import com.google.gwt.core.client.GWT;
 import com.google.gwt.core.client.JavaScriptObject;
 import com.google.gwt.core.client.JsArrayMixed;
 import com.google.gwt.core.client.JsArrayString;
@@ -36,6 +37,7 @@ public class JsCache extends JavaScriptObject {
   }-*/;
   
   public final void pushAll(JavaScriptObject prevElem) {
+    checkNull();
     JsCache c = prevElem.cast();
     for (int i = 0, ilen = c.length(); i < ilen; i++) {
       put(length(), c.get(i));
@@ -101,7 +103,7 @@ public class JsCache extends JavaScriptObject {
   
   public final <T extends JavaScriptObject> T getJavaScriptObject(Object name) {
     Object o = get(name); 
-    return (o instanceof JavaScriptObject) ? ((JavaScriptObject)o).<T>cast() : null;
+    return (o != null && o instanceof JavaScriptObject) ? ((JavaScriptObject)o).<T>cast() : null;
   }
 
   public final native boolean isEmpty() /*-{
@@ -128,6 +130,7 @@ public class JsCache extends JavaScriptObject {
   }-*/;
   
   public final int[] indexes() {
+    checkNull();
     JsArrayString a = keysImpl();
     int[] ret = new int[a.length()];
     for (int i = 0; i < a.length(); i++) {
@@ -141,6 +144,7 @@ public class JsCache extends JavaScriptObject {
   }
   
   public final String[] keys() {
+    checkNull();
     JsArrayString a = keysImpl();
     String[] ret = new String[a.length()];
     for (int i = 0; i < a.length(); i++) {
@@ -167,6 +171,13 @@ public class JsCache extends JavaScriptObject {
     return ret + "}";
   }
   
+  private void checkNull() {
+    // In dev-mode a null object casted to JavascriptObject does not throw a NPE
+    if (!GWT.isProdMode() && this == null) {
+      throw new NullPointerException();
+    }
+  }
+  
   private final native JsArrayString keysImpl() /*-{
     var key, keys=[];
     // Chrome in DevMode injects a property to JS objects
diff --git a/gwtquery-core/src/test/java/com/google/gwt/query/client/GQueryCoreTestGwt.java b/gwtquery-core/src/test/java/com/google/gwt/query/client/GQueryCoreTestGwt.java
index 347adb1a..370e3a1a 100644
--- a/gwtquery-core/src/test/java/com/google/gwt/query/client/GQueryCoreTestGwt.java
+++ b/gwtquery-core/src/test/java/com/google/gwt/query/client/GQueryCoreTestGwt.java
@@ -547,6 +547,13 @@ public class GQueryCoreTestGwt extends GWTTestCase {
     p = $$("({border:'1px solid black'})");
     assertEquals(1, p.keys().length);
     assertNotNull(p.getStr("border"));
+    
+    try {
+      // DevMode null casting return an object
+      ((Properties)null).toJsonString();
+      fail("Executing methods of a null object should throw a NullPointerException");
+    } catch (NullPointerException e) {
+    }
   }
 
   public void testRelativeMethods() {
-- 
2.39.5