Java tutorial
// // Copyright 2010 Cinch Logic Pty Ltd. // // http://www.chililog.com // // 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.chililog.server.data; import java.lang.reflect.Array; import java.text.SimpleDateFormat; import java.util.Date; import java.util.GregorianCalendar; import java.util.Map; import java.util.Set; import java.util.SimpleTimeZone; import java.util.regex.Pattern; import org.bson.types.BSONTimestamp; import org.bson.types.Binary; import org.bson.types.Code; import org.bson.types.CodeWScope; import org.bson.types.ObjectId; import com.mongodb.BasicDBObject; import com.mongodb.Bytes; import com.mongodb.DBObject; import com.mongodb.DBRefBase; /** * <p> * Serializer for mongoDB DBObjects into simple JSON * </p> * <p> * Modified from https://github.com/mongodb/mongo-java-driver/blob/master/src/main/com/mongodb/util/JSON.java. * </p> * <p> * Modified to support: * <ul> * <li>ObjectId - output as string rather than object like: <code>"_id" : { "$oid" : "4d8002fcf24599f624357467"}</code></li> * <li>Date - output as string rather than object like: * <code>"entry_timestamp" : { "$date" : "2011-03-16T00:23:24Z"}</code>.</li> * </p> */ public class MongoJsonSerializer { /** * Serializes an object into it's JSON form * * @param o * object to serialize * @return String containing JSON form of the object */ public static String serialize(Object o) { StringBuilder buf = new StringBuilder(); serialize(o, buf); return buf.toString(); } static void string(StringBuilder a, String s) { a.append("\""); for (int i = 0; i < s.length(); ++i) { char c = s.charAt(i); if (c == '\\') a.append("\\\\"); else if (c == '"') a.append("\\\""); else if (c == '\n') a.append("\\n"); else if (c == '\r') a.append("\\r"); else if (c == '\t') a.append("\\t"); else if (c == '\b') a.append("\\b"); else if (c < 32) continue; else a.append(c); } a.append("\""); } @SuppressWarnings({ "unchecked", "rawtypes" }) public static void serialize(Object o, StringBuilder buf) { o = Bytes.applyEncodingHooks(o); if (o == null) { buf.append(" null "); return; } if (o instanceof Number) { buf.append(o); return; } if (o instanceof String) { string(buf, o.toString()); return; } if (o instanceof Iterable) { boolean first = true; buf.append("[ "); for (Object n : (Iterable) o) { if (first) first = false; else buf.append(" , "); serialize(n, buf); } buf.append("]"); return; } if (o instanceof ObjectId) { // serialize(new BasicDBObject("$oid", o.toString()), buf); string(buf, o.toString()); return; } if (o instanceof DBObject) { boolean first = true; buf.append("{ "); DBObject dbo = (DBObject) o; for (String name : dbo.keySet()) { if (first) first = false; else buf.append(" , "); string(buf, name); buf.append(" : "); serialize(dbo.get(name), buf); } buf.append("}"); return; } if (o instanceof Map) { boolean first = true; buf.append("{ "); Map m = (Map) o; for (Map.Entry entry : (Set<Map.Entry>) m.entrySet()) { if (first) first = false; else buf.append(" , "); string(buf, entry.getKey().toString()); buf.append(" : "); serialize(entry.getValue(), buf); } buf.append("}"); return; } if (o instanceof Date) { Date d = (Date) o; SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'"); format.setCalendar(new GregorianCalendar(new SimpleTimeZone(0, "GMT"))); // serialize(new BasicDBObject("$date", format.format(d)), buf); string(buf, format.format(d)); return; } if (o instanceof DBRefBase) { buf.append(o); return; } if (o instanceof Boolean) { buf.append(o); return; } if (o instanceof byte[] || o instanceof Binary) { buf.append("<Binary Data>"); return; } if (o instanceof Pattern) { DBObject externalForm = new BasicDBObject(); externalForm.put("$regex", o.toString()); externalForm.put("$options", Bytes.regexFlags(((Pattern) o).flags())); serialize(externalForm, buf); return; } if (o.getClass().isArray()) { buf.append("[ "); for (int i = 0; i < Array.getLength(o); i++) { if (i > 0) buf.append(" , "); serialize(Array.get(o, i), buf); } buf.append("]"); return; } if (o instanceof BSONTimestamp) { BSONTimestamp t = (BSONTimestamp) o; buf.append(t.getTime()).append("|").append(t.getInc()); return; } if (o instanceof CodeWScope) { CodeWScope c = (CodeWScope) o; BasicDBObject temp = new BasicDBObject(); temp.put("$code", c.getCode()); temp.put("$scope", c.getScope()); serialize(temp, buf); return; } if (o instanceof Code) { string(buf, ((Code) o).getCode()); return; } throw new RuntimeException("json can't serialize type : " + o.getClass()); } }