writer.print("content b");
writer.close();
ObjectInserter newObjectInserter = db.newObjectInserter();
DirCache dc = db.lockDirCache();
DirCacheBuilder builder = dc.builder();
addEntryToBuilder("b.txt", file2, newObjectInserter, builder, 0);
addEntryToBuilder("a.txt", file, newObjectInserter, builder, 1);
writer = new PrintWriter(file);