commit 704f33f253ffd65721f236b722751316bcef3ff8
author David Su <dysu@google.com> Thu Jul 09 01:54:39 2020 -0700
committer David Su <dysu@google.com> Fri Jul 10 12:09:33 2020 -0700
tree 4672233c84a95ef9f3df0ff8e6cb76774b55964f
parent a0895c8580a76bded8b52bddeb7a6aaa3c099d08

StateMachine: check for null curState in dump()

After the StateMachine has quit, getCurrentState()
returns null, which will throw an exception in dump().

Bug: 160283853
Test: atest StateMachineTest
Change-Id: I4f9906eef6210b037d2170904a7c3aa483f5b4e9

core/java/com/android/internal/util/StateMachine.java

diff --git a/core/java/com/android/internal/util/StateMachine.java b/core/java/com/android/internal/util/StateMachine.java
index 0c24065..7a79cc9 100644
--- a/core/java/com/android/internal/util/StateMachine.java
+++ b/core/java/com/android/internal/util/StateMachine.java
@@ -2088,10 +2088,11 @@
         pw.println(getName() + ":");
         pw.println(" total records=" + getLogRecCount());
         for (int i = 0; i < getLogRecSize(); i++) {
-            pw.println(" rec[" + i + "]: " + getLogRec(i).toString());
+            pw.println(" rec[" + i + "]: " + getLogRec(i));
             pw.flush();
         }
-        pw.println("curState=" + getCurrentState().getName());
+        final IState curState = getCurrentState();
+        pw.println("curState=" + (curState == null ? "<QUIT>" : curState.getName()));
     }
 
     @Override

core/tests/utiltests/src/com/android/internal/util/StateMachineTest.java

diff --git a/core/tests/utiltests/src/com/android/internal/util/StateMachineTest.java b/core/tests/utiltests/src/com/android/internal/util/StateMachineTest.java
index 76aa93f..edf473e 100644
--- a/core/tests/utiltests/src/com/android/internal/util/StateMachineTest.java
+++ b/core/tests/utiltests/src/com/android/internal/util/StateMachineTest.java
@@ -16,27 +16,25 @@
 
 package com.android.internal.util;
 
-import java.util.Collection;
-import java.util.Iterator;
-
 import android.os.Debug;
 import android.os.HandlerThread;
 import android.os.Looper;
 import android.os.Message;
 import android.os.SystemClock;
 import android.os.test.TestLooper;
-
-import android.test.suitebuilder.annotation.Suppress;
-import com.android.internal.util.State;
-import com.android.internal.util.StateMachine;
-import com.android.internal.util.StateMachine.LogRec;
-
 import android.test.suitebuilder.annotation.MediumTest;
 import android.test.suitebuilder.annotation.SmallTest;
 import android.util.Log;
 
+import com.android.internal.util.StateMachine.LogRec;
+
 import junit.framework.TestCase;
 
+import java.io.PrintWriter;
+import java.io.StringWriter;
+import java.util.Collection;
+import java.util.Iterator;
+
 /**
  * Test for StateMachine.
  */
@@ -2013,4 +2011,12 @@
     private static void tloge(String s) {
         Log.e(TAG, s);
     }
+
+    public void testDumpDoesNotThrowNpeAfterQuit() {
+        final Hsm1 sm = Hsm1.makeHsm1();
+        sm.quitNow();
+        final StringWriter stringWriter = new StringWriter();
+        final PrintWriter printWriter = new PrintWriter(stringWriter);
+        sm.dump(null, printWriter, new String[0]);
+    }
 }