BZ-1019473: checking for null matches to avoid NPE on 'from' node

apache · Oct 18, 2013 · affb4e3 · affb4e3
1 parent 315cc8f
commit affb4e3
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Showing 2 changed files with 44 additions and 2 deletions.
diff --git a/drools-compiler/src/test/java/org/drools/compiler/integrationtests/Misc2Test.java b/drools-compiler/src/test/java/org/drools/compiler/integrationtests/Misc2Test.java
@@ -19,6 +19,7 @@
 import org.drools.compiler.Address;
 import org.drools.compiler.Cheese;
 import org.drools.compiler.CommonTestMethodBase;
+import org.drools.compiler.Message;
 import org.drools.compiler.Person;
 import org.drools.core.ClassObjectFilter;
 import org.drools.core.RuleBaseConfiguration;
@@ -146,6 +147,43 @@ public void testUpdateWithNonEffectiveActivations() throws Exception {
         ksession.dispose();
     }
 
+    @Test
+    public void testNPEOnMutableGlobal() throws Exception {
+        // BZ-1019473
+        String str = "package org.drools.compiler\n" +
+                "global java.util.List context\n" + 
+                "rule B\n" + 
+                "  when\n" +
+                "    Message( message == \"b\" )\n" +
+                "    $s : String() from context\n" + 
+                "  then\n" + 
+                "    System.out.println($s);\n" + 
+                "end";
+
+        KieServices ks = KieServices.Factory.get();
+        KieFileSystem kfs = ks.newKieFileSystem();
+        kfs.write(ResourceFactory.newByteArrayResource(str.getBytes()).setTargetPath("org/drools/compiler/rules.drl") );
+
+        KieBuilder kbuilder = KieServices.Factory.get().newKieBuilder(kfs);
+        kbuilder.buildAll();
+
+        assertEquals(0, kbuilder.getResults().getMessages().size());
+
+        ks.newKieContainer(kbuilder.getKieModule().getReleaseId()).getKieBase();
+        KieSession ksession = ks.newKieContainer(kbuilder.getKieModule().getReleaseId()).newKieSession();
+        assertNotNull( ksession );
+
+        List<String> context = new ArrayList<String>();
+        ksession.setGlobal("context", context);
+
+        FactHandle b = ksession.insert( new Message( "b" ) );
+        ksession.delete(b);
+        int fired = ksession.fireAllRules(1);
+
+        assertEquals( 0, fired );
+        ksession.dispose();
+    }
+
     @Test
     public void testClassNotFoundAfterDeserialization() throws Exception {
         // JBRULES-3670

diff --git a/drools-core/src/main/java/org/drools/core/phreak/PhreakFromNode.java b/drools-core/src/main/java/org/drools/core/phreak/PhreakFromNode.java
@@ -254,8 +254,12 @@ public void doLeftDeletes(FromNode fromNode,
             }
 
 
-            // @TODO (mdp) is this really necessary? won't the entire FH and RightTuple chaines just et GC'd?
-            unlinkCreatedHandles(leftTuple);
+            // if matches == null, the deletion might be happening before the fact was even propagated. See BZ-1019473 for details.
+            if( matches != null ) {
+
+                // @TODO (mdp) is this really necessary? won't the entire FH and RightTuple chaines just et GC'd?
+                unlinkCreatedHandles(leftTuple);
+            }
 
             leftTuple.clearStaged();
             leftTuple = next;