/*
* 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 org.bson;
import org.bson.util.ClassMap;
import java.util.List;
import java.util.concurrent.CopyOnWriteArrayList;
import java.util.regex.Pattern;
/**
* Contains byte representations of all the BSON types (see the <a href="http://bsonspec.org/spec.html">BSON Specification</a>). Also
* supports the registration of encoding and decoding hooks to transform BSON types during encoding or decoding.
*
* @see org.bson.Transformer
*/
public class BSON {
public static final byte EOO = 0;
public static final byte NUMBER = 1;
public static final byte STRING = 2;
public static final byte OBJECT = 3;
public static final byte ARRAY = 4;
public static final byte BINARY = 5;
public static final byte UNDEFINED = 6;
public static final byte OID = 7;
public static final byte BOOLEAN = 8;
public static final byte DATE = 9;
public static final byte NULL = 10;
public static final byte REGEX = 11;
public static final byte REF = 12;
public static final byte CODE = 13;
public static final byte SYMBOL = 14;
public static final byte CODE_W_SCOPE = 15;
public static final byte NUMBER_INT = 16;
public static final byte TIMESTAMP = 17;
public static final byte NUMBER_LONG = 18;
public static final byte MINKEY = -1;
public static final byte MAXKEY = 127;
// --- binary types
/*
these are binary types
so the format would look like
<BINARY><name><BINARY_TYPE><...>
*/
public static final byte B_GENERAL = 0;
public static final byte B_FUNC = 1;
public static final byte B_BINARY = 2;
public static final byte B_UUID = 3;
// --- regex flags
private static final int FLAG_GLOBAL = 256;
private static final int[] FLAG_LOOKUP = new int[Character.MAX_VALUE];
static {
FLAG_LOOKUP['g'] = FLAG_GLOBAL;
FLAG_LOOKUP['i'] = Pattern.CASE_INSENSITIVE;
FLAG_LOOKUP['m'] = Pattern.MULTILINE;
FLAG_LOOKUP['s'] = Pattern.DOTALL;
FLAG_LOOKUP['c'] = Pattern.CANON_EQ;
FLAG_LOOKUP['x'] = Pattern.COMMENTS;
FLAG_LOOKUP['d'] = Pattern.UNIX_LINES;
FLAG_LOOKUP['t'] = Pattern.LITERAL;
FLAG_LOOKUP['u'] = Pattern.UNICODE_CASE;
}
private static volatile boolean encodeHooks = false;
private static volatile boolean decodeHooks = false;
private static final ClassMap<List<Transformer>> encodingHooks = new ClassMap<List<Transformer>>();
private static final ClassMap<List<Transformer>> decodingHooks = new ClassMap<List<Transformer>>();
/**
* Gets whether any encoding transformers have been registered for any classes.
*
* @return true if any encoding hooks have been registered.
*/
public static boolean hasEncodeHooks() {
return encodeHooks;
}
/**
* Gets whether any decoding transformers have been registered for any classes.
*
* @return true if any decoding hooks have been registered.
*/
public static boolean hasDecodeHooks() {
return decodeHooks;
}
/**
* Registers a {@code Transformer} to use to encode a specific class into BSON.
*
* @param clazz the class to be transformed during encoding
* @param transformer the transformer to use during encoding
*/
public static void addEncodingHook(final Class<?> clazz, final Transformer transformer) {
encodeHooks = true;
List<Transformer> transformersForClass = encodingHooks.get(clazz);
if (transformersForClass == null) {
transformersForClass = new CopyOnWriteArrayList<Transformer>();
encodingHooks.put(clazz, transformersForClass);
}
transformersForClass.add(transformer);
}
/**
* Registers a {@code Transformer} to use when decoding a specific class from BSON. This class will be one of the basic types supported
* by BSON.
*
* @param clazz the class to be transformed during decoding
* @param transformer the transformer to use during decoding
*/
public static void addDecodingHook(final Class<?> clazz, final Transformer transformer) {
decodeHooks = true;
List<Transformer> transformersForClass = decodingHooks.get(clazz);
if (transformersForClass == null) {
transformersForClass = new CopyOnWriteArrayList<Transformer>();
decodingHooks.put(clazz, transformersForClass);
}
transformersForClass.add(transformer);
}
/**
* Transforms the {@code objectToEncode} using all transformers registered for the class of this object.
*
* @param objectToEncode the object being written to BSON.
* @return the transformed object
*/
public static Object applyEncodingHooks(final Object objectToEncode) {
Object transformedObject = objectToEncode;
if (!hasEncodeHooks() || objectToEncode == null || encodingHooks.size() == 0) {
return transformedObject;
}
List<Transformer> transformersForObject = encodingHooks.get(objectToEncode.getClass());
if (transformersForObject != null) {
for (final Transformer transformer : transformersForObject) {
transformedObject = transformer.transform(objectToEncode);
}
}
return transformedObject;
}
/**
* Transforms the {@code objectToDecode} using all transformers registered for the class of this object.
*
* @param objectToDecode the BSON object to decode
* @return the transformed object
*/
public static Object applyDecodingHooks(final Object objectToDecode) {
Object transformedObject = objectToDecode;
if (!hasDecodeHooks() || objectToDecode == null || decodingHooks.size() == 0) {
return transformedObject;
}
List<Transformer> transformersForObject = decodingHooks.get(objectToDecode.getClass());
if (transformersForObject != null) {
for (final Transformer transformer : transformersForObject) {
transformedObject = transformer.transform(objectToDecode);
}
}
return transformedObject;
}
/**
* Returns the encoding hook(s) associated with the specified class.
*
* @param clazz the class to fetch the encoding hooks for
* @return a List of encoding transformers that apply to the given class
*/
public static List<Transformer> getEncodingHooks(final Class<?> clazz) {
return encodingHooks.get(clazz);
}
/**
* Clears <em>all</em> encoding hooks.
*/
public static void clearEncodingHooks() {
encodeHooks = false;
encodingHooks.clear();
}
/**
* Remove all encoding hooks for a specific class.
*
* @param clazz the class to remove all the decoding hooks for
*/
public static void removeEncodingHooks(final Class<?> clazz) {
encodingHooks.remove(clazz);
}
/**
* Remove a specific encoding hook for a specific class. The {@code transformer} passed as the parameter must be {@code equals} to the
* transformer to remove.
*
* @param clazz the class to remove the encoding hook for
* @param transformer the specific encoding hook to remove.
*/
public static void removeEncodingHook(final Class<?> clazz, final Transformer transformer) {
getEncodingHooks(clazz).remove(transformer);
}
/**
* Returns the decoding hook(s) associated with the specific class
*
* @param clazz the class to fetch the decoding hooks for
* @return a List of all the decoding Transformers that apply to the given class
*/
public static List<Transformer> getDecodingHooks(final Class<?> clazz) {
return decodingHooks.get(clazz);
}
/**
* Clears <em>all</em> decoding hooks.
*/
public static void clearDecodingHooks() {
decodeHooks = false;
decodingHooks.clear();
}
/**
* Remove all decoding hooks for a specific class.
*
* @param clazz the class to remove all the decoding hooks for
*/
public static void removeDecodingHooks(final Class<?> clazz) {
decodingHooks.remove(clazz);
}
/**
* Remove a specific encoding hook for a specific class. The {@code transformer} passed as the parameter must be {@code equals} to the
* transformer to remove.
*
* @param clazz the class to remove the decoding hook for
* @param transformer the specific decoding hook to remove.
*/
public static void removeDecodingHook(final Class<?> clazz, final Transformer transformer) {
getDecodingHooks(clazz).remove(transformer);
}
/**
* Remove all decoding and encoding hooks for all classes.
*/
public static void clearAllHooks() {
clearEncodingHooks();
clearDecodingHooks();
}
// ----- static encode/decode -----
/**
* Encodes a DBObject as a BSON byte array.
*
* @param doc the document to encode
* @return the document encoded as BSON
*/
public static byte[] encode(final BSONObject doc) {
return new BasicBSONEncoder().encode(doc);
}
/**
* Decodes a BSON byte array into a DBObject instance.
*
* @param bytes a document encoded as BSON
* @return the document as a DBObject
*/
public static BSONObject decode(final byte[] bytes) {
return new BasicBSONDecoder().readObject(bytes);
}
/**
* Converts a sequence of regular expression modifiers from the database into Java regular expression flags.
*
* @param s regular expression modifiers
* @return the Java flags
* @throws IllegalArgumentException If sequence contains invalid flags.
*/
public static int regexFlags(final String s) {
int flags = 0;
if (s == null) {
return flags;
}
for (final char f : s.toLowerCase().toCharArray()) {
flags |= regexFlag(f);
}
return flags;
}
/**
* Converts a regular expression modifier from the database into Java regular expression flags.
*
* @param c regular expression modifier
* @return the Java flags
* @throws IllegalArgumentException If sequence contains invalid flags.
*/
public static int regexFlag(final char c) {
int flag = FLAG_LOOKUP[c];
if (flag == 0) {
throw new IllegalArgumentException(String.format("Unrecognized flag [%c]", c));
}
return flag;
}
/**
* Converts Java regular expression flags into regular expression modifiers from the database.
*
* @param flags the Java flags
* @return the Java flags
* @throws IllegalArgumentException if some flags couldn't be recognized.
*/
public static String regexFlags(final int flags) {
int processedFlags = flags;
StringBuilder buf = new StringBuilder();
for (int i = 0; i < FLAG_LOOKUP.length; i++) {
if ((processedFlags & FLAG_LOOKUP[i]) > 0) {
buf.append((char) i);
processedFlags -= FLAG_LOOKUP[i];
}
}
if (processedFlags > 0) {
throw new IllegalArgumentException("Some flags could not be recognized.");
}
return buf.toString();
}
/**
* Provides an integer representation of Boolean or Number. If argument is {@link Boolean}, then {@code 1} for {@code true} will be
* returned or @{code 0} otherwise. If argument is {@code Number}, then {@link Number#intValue()} will be called.
*
* @param number the number to convert to an int
* @return integer value
* @throws IllegalArgumentException if the argument is {@code null} or not {@link Boolean} or {@link Number}
*/
public static int toInt(final Object number) {
if (number == null) {
throw new IllegalArgumentException("Argument shouldn't be null");
}
if (number instanceof Number) {
return ((Number) number).intValue();
}
if (number instanceof Boolean) {
return ((Boolean) number) ? 1 : 0;
}
throw new IllegalArgumentException("Can't convert: " + number.getClass().getName() + " to int");
}
}