Fixed #49

Author: cowtowncoder

jr-objects/src/main/java/com/fasterxml/jackson/jr/ob/impl/DeferredMap.java

@@ -149,10 +149,12 @@ private final int _newSize(int size)
         if (size < 200) {
             return size+size;
         }
+        // note: MUST ensure it's divisible by two (that is, last bit is 0), because
+        // always adding values in pairs, but checking size before add
         if (size < 2000) {
-            return size + (size>>1);
+            return size + ((size>>1) & ~1);
         }
-        return size + (size>>2);
+        return size + ((size>>2) & ~1);
     }
 
     protected Map<Object,Object> _buildMap(int expSize)

jr-objects/src/test/java/com/fasterxml/jackson/jr/ob/ReadMapTest.java

@@ -0,0 +1,27 @@
+package com.fasterxml.jackson.jr.ob;
+
+import java.util.*;
+
+import com.fasterxml.jackson.jr.ob.JSON;
+
+// for [jackson-jr#49], where `DeferredMap` explodes
+public class ReadMapTest extends TestBase
+{
+    public void testIssues49() throws Exception
+    {
+        for (int i : new int[] { 7, 99, 513, 1099, 3003, 5005, 10001, 90003, 111111 }) {
+            testLargeJson(i);
+        }
+    }
+
+    private void testLargeJson(int size) throws Exception {
+        Map<String, Object> map = new HashMap<String, Object>();
+        for (int i = 0; i < size; i++) {
+            map.put("" + i, new HashMap<String, Object>());
+        }
+        String json = JSON.std.asString(map);
+        Map<?,?> result = JSON.std.mapFrom(json);
+        assertNotNull(result);
+        assertEquals(size, result.size());
+    }
+}

release-notes/VERSION

@@ -4,6 +4,11 @@ Project: jackson-jr
 === Releases ===
 ------------------------------------------------------------------------
 
+2.7.9 (not yet released)
+
+#49: ArrayIndexOutOfBoundsException when parsing large Map
+ (reported by Michael J)
+
 2.7.8 (26-Sep-2016)
 2.7.7 (27-Aug-2016)
 2.7.6 (23-Jul-2016)