5045147: Prevent insertion of null Key into empty TreeMap (and null element into TreeSet) when no Comparator is used. Prevent insertion of key of incorrect type into empty TreeMap and incorrect type element into TreeSet and incorrect type when Comparator is used

Reviewed-by: alanb, dl, mduigou

jdk/src/share/classes/java/util/TreeMap.java

@@ -528,11 +528,8 @@ public class TreeMap<K,V>
     public V put(K key, V value) {
         Entry<K,V> t = root;
         if (t == null) {
-            // TBD:
-            // 5045147: (coll) Adding null to an empty TreeSet should
-            // throw NullPointerException
-            //
-            // compare(key, key); // type check
+            compare(key, key); // type (and possibly null) check
+
             root = new Entry<>(key, value, null);
             size = 1;
             modCount++;

jdk/test/java/util/TreeMap/cr5045147.java

@@ -0,0 +1,118 @@
+/*
+ * Copyright (c) 2006, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 5045147
+ * @summary Test handling of null with empty Map
+ * @author Mike Duigou
+ */
+
+import java.util.*;
+import java.util.concurrent.*;
+import java.util.concurrent.atomic.*;
+import java.lang.reflect.*;
+
+public class cr5045147 {
+
+    static void realMain(String[] args) throws Throwable {
+        // No comparator
+        Map<String,String> comparable = new TreeMap<>();
+
+        // insert null into empty map (504517 failure)
+        try {
+            comparable.put(null, "anything");
+            fail("null shouldn't be accepted");
+        } catch(NullPointerExecption failed) {
+            pass();
+        }
+
+        // insert non-null into empty map
+        try {
+            comparable.put("test", "anything");
+            pass();
+        } catch(NullPointerExecption failed) {
+            fail();
+        }
+
+        // insert null into non-empty map
+        try {
+            comparable.put(null, "anything");
+            fail("null shouldn't be accepted");
+        } catch(NullPointerExecption failed) {
+            pass();
+        }
+
+        Map<String,String> comparator = new TreeMap<>(String.CASE_INSENSITIVE_ORDER);
+
+        // insert null into empty map (504517 failure)
+        try {
+            comparator.put(null, "anything");
+            fail("null shouldn't be accepted");
+        } catch(NullPointerExecption failed) {
+            pass();
+        }
+
+        // insert non-null into empty map
+        try {
+            comparator.put("test", "anything");
+            pass();
+        } catch(NullPointerExecption failed) {
+            fail();
+        }
+
+        // insert null into non-empty map
+        try {
+            comparator.put(null, "anything");
+            fail("null shouldn't be accepted");
+        } catch(NullPointerExecption failed) {
+            pass();
+        }
+
+        comparator.clear();
+
+        // insert non-String into empty map (504517 failure)
+        try {
+            comparator.put(new Object(), "anything");
+            fail("Object shouldn't be accepted");
+        } catch(ClassCastExecption failed) {
+            pass();
+        }
+
+    }
+
+    //--------------------- Infrastructure ---------------------------
+    static volatile int passed = 0, failed = 0;
+    static void pass() {passed++;}
+    static void fail() {failed++; Thread.dumpStack();}
+    static void fail(String msg) {System.out.println(msg); fail();}
+    static void unexpected(Throwable t) {failed++; t.printStackTrace();}
+    static void check(boolean cond) {if (cond) pass(); else fail();}
+    static void equal(Object x, Object y) {
+        if (x == null ? y == null : x.equals(y)) pass();
+        else fail(x + " not equal to " + y);}
+    public static void main(String[] args) throws Throwable {
+        try {realMain(args);} catch (Throwable t) {unexpected(t);}
+        System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);
+        if (failed > 0) throw new AssertionError("Some tests failed");}
+}