/*
    * Copyright 2002-2019 the original author or authors.
    *
    * 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
    *
    *      https://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.springframework.security.oauth2.common.util;
  
  import java.io.IOException;
  import java.text.SimpleDateFormat;
  import java.util.Date;
  
  import com.fasterxml.jackson.core.JsonGenerator;
  import com.fasterxml.jackson.core.JsonProcessingException;
  import com.fasterxml.jackson.databind.JsonSerializer;
  import com.fasterxml.jackson.databind.SerializerProvider;
  
  /**
   * JSON serializer for Jackson to handle regular date instances as timestamps in ISO format.
   * 
   * @author Dave Syer
   * 
   */
  public class JsonDateSerializer extends JsonSerializer<Date> {
  
  	private static final SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
  
  	@Override
  	public void serialize(Date date, JsonGenerator generator, SerializerProvider provider) throws IOException,
  			JsonProcessingException {
  		synchronized (dateFormat) {
  			String formatted = dateFormat.format(date);
  			generator.writeString(formatted);
  		}
  	}
  
  }