001// ***************************************************************************************************************************
002// * Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements.  See the NOTICE file *
003// * distributed with this work for additional information regarding copyright ownership.  The ASF licenses this file        *
004// * to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance            *
005// * with the License.  You may obtain a copy of the License at                                                              *
006// *                                                                                                                         *
007// *  http://www.apache.org/licenses/LICENSE-2.0                                                                             *
008// *                                                                                                                         *
009// * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an  *
010// * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the License for the        *
011// * specific language governing permissions and limitations under the License.                                              *
012// ***************************************************************************************************************************
013package org.apache.juneau.rest.helper;
014
015import java.io.*;
016import java.util.*;
017
018import org.apache.juneau.http.*;
019
020/**
021 * Builder class for constructing {@link StreamResource} objects.
022 *
023 * <h5 class='section'>See Also:</h5>
024 * <ul>
025 *    <li class='link'>{@doc juneau-rest-server.RestMethod.StreamResource}
026 * </ul>
027 */
028public final class StreamResourceBuilder {
029   ArrayList<Object> contents = new ArrayList<>();
030   MediaType mediaType;
031   Map<String,Object> headers = new LinkedHashMap<>();
032
033   /**
034    * Specifies the resource media type string.
035    *
036    * @param mediaType The resource media type string.
037    * @return This object (for method chaining).
038    */
039   public StreamResourceBuilder mediaType(String mediaType) {
040      this.mediaType = MediaType.forString(mediaType);
041      return this;
042   }
043
044   /**
045    * Specifies the resource media type string.
046    *
047    * @param mediaType The resource media type string.
048    * @return This object (for method chaining).
049    */
050   public StreamResourceBuilder mediaType(MediaType mediaType) {
051      this.mediaType = mediaType;
052      return this;
053   }
054
055   /**
056    * Specifies the contents for this resource.
057    *
058    * <p>
059    * This method can be called multiple times to add more content.
060    *
061    * @param contents
062    *    The resource contents.
063    *    <br>If multiple contents are specified, the results will be concatenated.
064    *    <br>Contents can be any of the following:
065    *    <ul>
066    *       <li><code><jk>byte</jk>[]</code>
067    *       <li><code>InputStream</code>
068    *       <li><code>Reader</code> - Converted to UTF-8 bytes.
069    *       <li><code>File</code>
070    *       <li><code>CharSequence</code> - Converted to UTF-8 bytes.
071    *    </ul>
072    * @return This object (for method chaining).
073    */
074   public StreamResourceBuilder contents(Object...contents) {
075      this.contents.addAll(Arrays.asList(contents));
076      return this;
077   }
078
079   /**
080    * Specifies an HTTP response header value.
081    *
082    * @param name The HTTP header name.
083    * @param value
084    *    The HTTP header value.
085    *    <br>Will be converted to a <code>String</code> using {@link Object#toString()}.
086    * @return This object (for method chaining).
087    */
088   public StreamResourceBuilder header(String name, Object value) {
089      this.headers.put(name, value);
090      return this;
091   }
092
093   /**
094    * Specifies HTTP response header values.
095    *
096    * @param headers
097    *    The HTTP headers.
098    *    <br>Values will be converted to <code>Strings</code> using {@link Object#toString()}.
099    * @return This object (for method chaining).
100    */
101   public StreamResourceBuilder headers(Map<String,Object> headers) {
102      this.headers.putAll(headers);
103      return this;
104   }
105
106   /**
107    * Create a new {@link StreamResource} using values in this builder.
108    *
109    * @return A new immutable {@link StreamResource} object.
110    * @throws IOException
111    */
112   public StreamResource build() throws IOException {
113      return new StreamResource(mediaType, headers, contents.toArray());
114   }
115}