Java tutorial
/* * Copyright 2008-present MongoDB, Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.mongodb; import org.bson.BSONObject; import org.bson.BasicBSONEncoder; import org.bson.io.OutputBuffer; /** * The default BSON encoder for BSONObject instances. */ public class DefaultDBEncoder extends BasicBSONEncoder implements DBEncoder { @Override public int writeObject(final OutputBuffer outputBuffer, final BSONObject document) { set(outputBuffer); int x = putObject(document); done(); return x; } @Override protected boolean putSpecial(final String name, final Object value) { if (value instanceof DBRef) { putDBRef(name, (DBRef) value); return true; } else { return false; } } /** * Deals with encoding database references. * * @param name the name of the field in the document * @param ref the database reference object */ protected void putDBRef(final String name, final DBRef ref) { BasicDBObject dbRefDocument = new BasicDBObject("$ref", ref.getCollectionName()).append("$id", ref.getId()); if (ref.getDatabaseName() != null) { dbRefDocument.put("$db", ref.getDatabaseName()); } putObject(name, dbRefDocument); } @Override public String toString() { return String.format("DBEncoder{class=%s}", getClass().getName()); } public static final DBEncoderFactory FACTORY = new DBEncoderFactory() { @Override public DBEncoder create() { return new DefaultDBEncoder(); } }; }