/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 trailers;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.HashMap;
import java.util.Map;
import java.util.function.Supplier;
import jakarta.servlet.ServletException;
import jakarta.servlet.http.HttpServlet;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
/**
* This example writes some trailer fields to the HTTP response.
*/
public class ResponseTrailers extends HttpServlet {
private static final long serialVersionUID = 1L;
private static final Supplier<Map<String,String>> TRAILER_FIELD_SUPPLIER =
new TrailerFieldSupplier();
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
resp.setTrailerFields(TRAILER_FIELD_SUPPLIER);
resp.setContentType("text/plain");
resp.setCharacterEncoding("UTF-8");
PrintWriter pw = resp.getWriter();
pw.print("This response should include trailer fields.");
}
private static class TrailerFieldSupplier implements Supplier<Map<String,String>> {
private static final Map<String,String> trailerFields = new HashMap<>();
static {
trailerFields.put("x-trailer-1", "Trailer value one");
trailerFields.put("x-trailer-2", "Trailer value two");
}
@Override
public Map<String, String> get() {
return trailerFields;
}
}
}