All Downloads are FREE. Search and download functionalities are using the official Maven repository.

com.mongodb.BasicDBObjectBuilder Maven / Gradle / Ivy

Go to download

The MongoDB Java Driver uber-artifact, containing mongodb-driver, mongodb-driver-core, and bson

There is a newer version: 3.1.0
Show newest version
/*
 * Copyright (c) 2008-2014 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 java.util.Iterator;
import java.util.LinkedList;
import java.util.Map;

/**
 * 

Utility for building complex objects. For example:

*
 *   {@code BasicDBObjectBuilder.start().add( "name" , "eliot").add("number" , 17).get()}
 * 
*/ public class BasicDBObjectBuilder { /** * Creates a builder intialized with an empty document. */ public BasicDBObjectBuilder(){ _stack = new LinkedList(); _stack.add( new BasicDBObject() ); } /** * Creates a builder intialized with an empty document. * * @return The new empty builder */ public static BasicDBObjectBuilder start(){ return new BasicDBObjectBuilder(); } /** * Creates a builder initialized with the given key/value. * * @param key The field name * @param val The value * @return the new builder */ public static BasicDBObjectBuilder start(final String key, final Object val) { return (new BasicDBObjectBuilder()).add(key, val); } /** * Creates an object builder from an existing map of key value pairs. * * @param map map to use * @return the new builder */ @SuppressWarnings("unchecked") public static BasicDBObjectBuilder start(final Map map){ BasicDBObjectBuilder b = new BasicDBObjectBuilder(); Iterator i = map.entrySet().iterator(); while (i.hasNext()) { Map.Entry entry = i.next(); b.add(entry.getKey().toString(), entry.getValue()); } return b; } /** * Appends the key/value to the active object * * @param key the field name * @param val the value of the field * @return {@code this} so calls can be chained */ public BasicDBObjectBuilder append(final String key, final Object val) { _cur().put( key , val ); return this; } /** * Same as append * * @param key the field name * @param val the value of the field * @return {@code this} so calls can be chained * @see #append(String, Object) */ public BasicDBObjectBuilder add(final String key, final Object val) { return append(key, val); } /** * Creates an new empty object and inserts it into the current object with the given key. The new child object becomes the active one. * * @param key the field name * @return {@code this} so calls can be chained */ public BasicDBObjectBuilder push(final String key) { BasicDBObject o = new BasicDBObject(); _cur().put( key , o ); _stack.addLast( o ); return this; } /** * Pops the active object, which means that the parent object becomes active * * @return {@code this} so calls can be chained */ public BasicDBObjectBuilder pop(){ if ( _stack.size() <= 1 ) throw new IllegalArgumentException( "can't pop last element" ); _stack.removeLast(); return this; } /** * Gets the top level document. * * @return The base object */ public DBObject get(){ return _stack.getFirst(); } /** * Returns true if no key/value was inserted into the top level document. * * @return true if empty */ public boolean isEmpty(){ return ((BasicDBObject) _stack.getFirst()).size() == 0; } private DBObject _cur(){ return _stack.getLast(); } private final LinkedList _stack; }




© 2015 - 2024 Weber Informatics LLC | Privacy Policy