XContentBuilder builder = jsonBuilder();
builder.startObject()
.field("shardId", shardId)
.field("numDeletions", reader.numDeletedDocs());
builder.startArray("docs");
FieldInfos fieldInfos = reader.getFieldInfos();
Bits live = MultiFields.getLiveDocs(reader);
for (int docNum = 0; docNum < reader.maxDoc(); docNum++) {
Document doc = reader.document(docNum);
if (live != null && live.get(docNum)) {
continue; // not deleted