Hi,
On Jun 4, 2013, at 1:34 AM, Brent Christian <brent.christ...@oracle.com> wrote:
> Hi, Paul
>
> If a HashMap is created via serialization or clone(), we don't check if the
> table needs resizing when adding entries, but still need to check if a bin
> should be converted to a TreeBin. In this case, putForCreate() calls
> createEntry() directly, instead of addEntry().
>
But putForCreate calculates "checkIfNeedTree":
1161 if (table[i] instanceof Entry) {
1162 int listSize = 0;
1163 Entry<K,V> e = (Entry<K,V>) table[i];
1164 for (; e != null; e = (Entry<K,V>)e.next) {
1165 Object k;
1166 if (e.hash == hash && ((k = e.key) == key ||
key.equals(k))) {
1167 e.value = value;
1168 return;
1169 }
1170 listSize++;
1171 }
1172 // Didn't find, fall through to createEntry().
1173 // Check for conversion to TreeBin done via createEntry().
1174 checkIfNeedTree = listSize >= TreeBin.TREE_THRESHOLD;
1175 } else if (table[i] != null) {
...
1186
1187 createEntry(hash, key, value, i, checkIfNeedTree);
1188 }
So the call to createEntry is just recalculating the same "listSize" value:
2232 void createEntry(int hash, K key, V value, int bucketIndex, boolean
checkIfNeedTree) {
...
2239 if (checkIfNeedTree) {
2240 int listSize = 0;
2241 for (e = (Entry<K,V>) table[bucketIndex]; e != null; e =
(Entry<K,V>)e.next) {
2242 listSize++;
2243 if (listSize >= TreeBin.TREE_THRESHOLD) { // Convert to
TreeBin
2244 if (comparableClassFor(key) != null) {
2245 TreeBin t = new TreeBin();
2246 t.populate((Entry)table[bucketIndex]);
2247 table[bucketIndex] = t;
2248 }
2249 break;
2250 }
2251 }
2252 }
Paul.
> Thanks,
> -Brent
>
> On 6/3/13 12:56 AM, Paul Sandoz wrote:
>> Hi Brent,
>>
>> A minor thing: take it or leave it :-)
>>
>> In HashMap:
>>
>> 2207 void addEntry(int hash, K key, V value, int bucketIndex, boolean
>> checkIfNeedTree) {
>> 2208 // assert key != null;
>> 2209 if ((size >= threshold) && (null != table[bucketIndex])) {
>> 2210 resize(2 * table.length);
>> 2211 hash = hash(key);
>> 2212 bucketIndex = indexFor(hash, table.length);
>> 2213 }
>> 2214 createEntry(hash, key, value, bucketIndex, checkIfNeedTree);
>> 2215 }
>>
>> You could re-verify the bucket size if the table is resized rather
> than in createEntry, since that AFAICT is the only case where conditions
> after the call to addEntry might change.
>>
>> Pau.
>>
