http://www.mongodb.org: The Java operations layer for the MongoDB Java Driver. Third parties can wrap this layer to provide custom higher-level APIs
  • Various (MongoDB) 
/*
 * 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.BasicBSONObject;
import org.bson.BsonBinaryWriter;
import org.bson.BsonDocument;
import org.bson.BsonDocumentWrapper;
import org.bson.codecs.Decoder;
import org.bson.codecs.DecoderContext;
import org.bson.codecs.Encoder;
import org.bson.codecs.EncoderContext;
import org.bson.codecs.configuration.CodecRegistry;
import org.bson.conversions.Bson;
import org.bson.io.BasicOutputBuffer;
import org.bson.io.OutputBuffer;
import org.bson.json.JsonReader;
import org.bson.json.JsonWriter;
import org.bson.json.JsonWriterSettings;
import org.bson.types.BasicBSONList;

import java.io.StringWriter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.TreeSet;


A basic implementation of BSON object that is MongoDB specific. A DBObject can be created as follows, using this class: 
DBObject obj = new BasicDBObject();
obj.put( "foo", "bar" );



@mongodb.driver.manualcore/document/ MongoDB Documents
/**
 * A basic implementation of BSON object that is MongoDB specific. A {@code DBObject} can be created as follows, using this class:
 * <pre>
 * DBObject obj = new BasicDBObject();
 * obj.put( "foo", "bar" );
 * </pre>
 *
 * @mongodb.driver.manual core/document/ MongoDB Documents
 */
@SuppressWarnings({"rawtypes"})
public class BasicDBObject extends BasicBSONObject implements DBObject, Bson {
    private static final long serialVersionUID = -4415279469780082174L;

    private boolean isPartialObject;

    
Parses a string in MongoDB Extended JSON format to a BasicDBObject. 
Params:
  • json – the JSON string
See Also:
Returns:a corresponding BasicDBObject object
@mongodb.driver.manualreference/mongodb-extended-json/ MongoDB Extended JSON
/**
     * Parses a string in MongoDB Extended JSON format to a {@code BasicDBObject}.
     *
     * @param json the JSON string
     * @return a corresponding {@code BasicDBObject} object
     * @see org.bson.json.JsonReader
     * @mongodb.driver.manual reference/mongodb-extended-json/ MongoDB Extended JSON
     */
    public static BasicDBObject parse(final String json) {
        return parse(json, DBObjectCodec.getDefaultRegistry().get(BasicDBObject.class));
    }

    
Parses a string in MongoDB Extended JSON format to a BasicDBObject. 
Params:
  • json – the JSON string
  • decoder – the decoder to use to decode the BasicDBObject instance
See Also:
Returns:a corresponding BasicDBObject object
@mongodb.driver.manualreference/mongodb-extended-json/ MongoDB Extended JSON
/**
     * Parses a string in MongoDB Extended JSON format to a {@code BasicDBObject}.
     *
     * @param json the JSON string
     * @param decoder the decoder to use to decode the BasicDBObject instance
     * @return a corresponding {@code BasicDBObject} object
     * @see org.bson.json.JsonReader
     * @mongodb.driver.manual reference/mongodb-extended-json/ MongoDB Extended JSON
     */
    public static BasicDBObject parse(final String json, final Decoder<BasicDBObject> decoder) {
        return decoder.decode(new JsonReader(json), DecoderContext.builder().build());
    }

    
Creates an empty object.

/**
     * Creates an empty object.
     */
    public BasicDBObject() {
        super();
    }

    
Creates an empty object

Params:
  • size – an estimate of number of fields that will be inserted
/**
     * Creates an empty object
     *
     * @param size an estimate of number of fields that will be inserted
     */
    public BasicDBObject(final int size) {
        super(size);
    }

    
Creates an object with the given key/value

Params:
  • key –   key under which to store
  • value – value to store
/**
     * Creates an object with the given key/value
     *
     * @param key   key under which to store
     * @param value value to store
     */
    public BasicDBObject(final String key, final Object value) {
        super(key, value);
    }

    
Creates an object from a map.

Params:
  • map – map to convert
/**
     * Creates an object from a map.
     *
     * @param map map to convert
     */
    public BasicDBObject(final Map map) {
        super(map);
    }

    
Add a key/value pair to this object

Params:
  • key – the field name
  • val – the field value
Returns:this BasicDBObject with the new values added
/**
     * Add a key/value pair to this object
     *
     * @param key the field name
     * @param val the field value
     * @return this BasicDBObject with the new values added
     */
    @Override
    public BasicDBObject append(final String key, final Object val) {
        put(key, val);
        return this;
    }

    
Whether markAsPartialObject was ever called only matters if you are going to upsert and do not want to risk losing fields. 
Returns:true if this has been marked as a partial object
/**
     * Whether {@link #markAsPartialObject} was ever called only matters if you are going to upsert and do not want to risk losing fields.
     *
     * @return true if this has been marked as a partial object
     */
    @Override
    public boolean isPartialObject() {
        return isPartialObject;
    }

    
Gets a JSON representation of this document using the JsonMode.STRICT output mode, and otherwise the default settings of Builder and DBObjectCodec. 
Throws:
See Also:
Returns:a JSON representation of this document
/**
     * Gets a JSON representation of this document using the {@link org.bson.json.JsonMode#STRICT} output mode, and otherwise the default
     * settings of {@link JsonWriterSettings.Builder} and {@link DBObjectCodec}.
     *
     * @return a JSON representation of this document
     * @throws org.bson.codecs.configuration.CodecConfigurationException if the document contains types not in the default registry
     * @see #toJson(JsonWriterSettings)
     * @see JsonWriterSettings
     */
    @SuppressWarnings("deprecation")
    public String toJson() {
        return toJson(new JsonWriterSettings());
    }

    
Gets a JSON representation of this document

With the default DBObjectCodec.


Params:
  • writerSettings – the json writer settings to use when encoding
Throws:
Returns:a JSON representation of this document
/**
     * Gets a JSON representation of this document
     *
     * <p>With the default {@link DBObjectCodec}.</p>
     *
     * @param writerSettings the json writer settings to use when encoding
     * @return a JSON representation of this document
     * @throws org.bson.codecs.configuration.CodecConfigurationException if the document contains types not in the default registry
     */
    public String toJson(final JsonWriterSettings writerSettings) {
        return toJson(writerSettings, DBObjectCodec.getDefaultRegistry().get(BasicDBObject.class));
    }

    
Gets a JSON representation of this document

With the default JsonWriterSettings.


Params:
  • encoder – the BasicDBObject codec instance to encode the document with
Throws:
Returns:a JSON representation of this document
/**
     * Gets a JSON representation of this document
     *
     * <p>With the default {@link JsonWriterSettings}.</p>
     *
     * @param encoder the BasicDBObject codec instance to encode the document with
     * @return a JSON representation of this document
     * @throws org.bson.codecs.configuration.CodecConfigurationException if the registry does not contain a codec for the document values.
     */
    @SuppressWarnings("deprecation")
    public String toJson(final Encoder<BasicDBObject> encoder) {
        return toJson(new JsonWriterSettings(), encoder);
    }

    
Gets a JSON representation of this document

Params:
  • writerSettings – the json writer settings to use when encoding
  • encoder – the BasicDBObject codec instance to encode the document with
Throws:
Returns:a JSON representation of this document
/**
     * Gets a JSON representation of this document
     *
     * @param writerSettings the json writer settings to use when encoding
     * @param encoder the BasicDBObject codec instance to encode the document with
     * @return a JSON representation of this document
     * @throws org.bson.codecs.configuration.CodecConfigurationException if the registry does not contain a codec for the document values.
     */
    public String toJson(final JsonWriterSettings writerSettings, final Encoder<BasicDBObject> encoder) {
        JsonWriter writer = new JsonWriter(new StringWriter(), writerSettings);
        encoder.encode(writer, this, EncoderContext.builder().build());
        return writer.getWriter().toString();
    }

    @Override
    public boolean equals(final Object o) {
        if (o == this) {
            return true;
        }

        if (!(o instanceof BSONObject)) {
            return false;
        }

        BSONObject other = (BSONObject) o;

        if (!keySet().equals(other.keySet())) {
            return false;
        }

        return Arrays.equals(toBson(canonicalizeBSONObject(this)), toBson(canonicalizeBSONObject(other)));
    }

    @Override
    public int hashCode() {
        return Arrays.hashCode(toBson(canonicalizeBSONObject(this)));
    }

    private static byte[] toBson(final DBObject dbObject) {
        OutputBuffer outputBuffer = new BasicOutputBuffer();
        DBObjectCodec.getDefaultRegistry().get(DBObject.class).encode(new BsonBinaryWriter(outputBuffer), dbObject,
                EncoderContext.builder().build());
        return outputBuffer.toByteArray();
    }

    
Returns a JSON serialization of this object


The output will look like:  {"a":1, "b":["x","y","z"]} 


Returns:JSON serialization
/**
     * <p>Returns a JSON serialization of this object</p>
     *
     * <p>The output will look like: {@code  {"a":1, "b":["x","y","z"]} }</p>
     *
     * @return JSON serialization
     */
    @SuppressWarnings("deprecation")
    public String toString() {
        return toJson();
    }

    
If this object was retrieved with only some fields (using a field filter) this method will be called to mark it as such.

/**
     * If this object was retrieved with only some fields (using a field filter) this method will be called to mark it as such.
     */
    @Override
    public void markAsPartialObject() {
        isPartialObject = true;
    }

    
Creates a new instance which is a copy of this BasicDBObject.

Returns:a BasicDBObject with exactly the same values as this instance.
/**
     * Creates a new instance which is a copy of this BasicDBObject.
     *
     * @return a BasicDBObject with exactly the same values as this instance.
     */
    public Object copy() {
        // copy field values into new object
        BasicDBObject newCopy = new BasicDBObject(this.toMap());
        // need to clone the sub obj
        for (final String field : keySet()) {
            Object val = get(field);
            if (val instanceof BasicDBObject) {
                newCopy.put(field, ((BasicDBObject) val).copy());
            } else if (val instanceof BasicDBList) {
                newCopy.put(field, ((BasicDBList) val).copy());
            }
        }
        return newCopy;
    }

    @Override
    public <TDocument> BsonDocument toBsonDocument(final Class<TDocument> documentClass, final CodecRegistry codecRegistry) {
        return new BsonDocumentWrapper<BasicDBObject>(this, codecRegistry.get(BasicDBObject.class));
    }

    // create a copy of "from", but with keys ordered alphabetically
    @SuppressWarnings("unchecked")
    private static Object canonicalize(final Object from) {
        if (from instanceof BSONObject && !(from instanceof BasicBSONList)) {
            return canonicalizeBSONObject((BSONObject) from);
        } else if (from instanceof List) {
            return canonicalizeList((List<Object>) from);
        } else if (from instanceof Map) {
            return canonicalizeMap((Map<String, Object>) from);
        } else {
            return from;
        }
    }

    private static Map<String, Object> canonicalizeMap(final Map<String, Object> from) {
        Map<String, Object> canonicalized = new LinkedHashMap<String, Object>(from.size());
        TreeSet<String> keysInOrder = new TreeSet<String>(from.keySet());
        for (String key : keysInOrder) {
            Object val = from.get(key);
            canonicalized.put(key, canonicalize(val));
        }
        return canonicalized;
    }

    private static DBObject canonicalizeBSONObject(final BSONObject from) {
        BasicDBObject canonicalized = new BasicDBObject();
        TreeSet<String> keysInOrder = new TreeSet<String>(from.keySet());
        for (String key : keysInOrder) {
            Object val = from.get(key);
            canonicalized.put(key, canonicalize(val));
        }
        return canonicalized;
    }

    private static List canonicalizeList(final List<Object> list) {
        List<Object> canonicalized = new ArrayList<Object>(list.size());
        for (Object cur : list) {
            canonicalized.add(canonicalize(cur));
        }
        return canonicalized;
    }
}