001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.juneau.http.part;
018
019import static org.apache.juneau.commons.utils.Utils.*;
020
021import java.util.*;
022import java.util.function.*;
023
024import org.apache.http.*;
025import org.apache.juneau.assertions.*;
026
027/**
028 * A {@link NameValuePair} that consists of a single string value.
029 *
030 * <h5 class='section'>See Also:</h5><ul>
031 *    <li class='link'><a class="doclink" href="https://juneau.apache.org/docs/topics/JuneauRestCommonBasics">juneau-rest-common Basics</a>
032 * </ul>
033 */
034public class BasicStringPart extends BasicPart {
035   /**
036    * Static creator.
037    *
038    * @param name The part name.
039    * @param value The part value.
040    * @return A new {@link BasicStringPart} object, or <jk>null</jk> if the name or value is <jk>null</jk>.
041    */
042   public static BasicStringPart of(String name, String value) {
043      if (e(name) || value == null)
044         return null;
045      return new BasicStringPart(name, value);
046   }
047
048   /**
049    * Static creator with delayed value.
050    *
051    * <p>
052    * Part value is re-evaluated on each call to {@link NameValuePair#getValue()}.
053    *
054    * @param name The part name.
055    * @param value The part value supplier.
056    * @return A new {@link BasicStringPart} object, or <jk>null</jk> if the name or supplier is <jk>null</jk>.
057    */
058   public static BasicStringPart of(String name, Supplier<String> value) {
059      if (e(name) || value == null)
060         return null;
061      return new BasicStringPart(name, value);
062   }
063
064   private final String value;
065   private final Supplier<String> supplier;
066
067   /**
068    * Constructor.
069    *
070    * @param name The part name.  Must not be <jk>null</jk>.
071    * @param value The part value.  Can be <jk>null</jk>.
072    */
073   public BasicStringPart(String name, String value) {
074      super(name, value);
075      this.value = value;
076      this.supplier = null;
077   }
078
079   /**
080    * Constructor.
081    *
082    * @param name The part name.  Must not be <jk>null</jk>.
083    * @param value The part value supplier.  Can be <jk>null</jk> or supply <jk>null</jk>.
084    */
085   public BasicStringPart(String name, Supplier<String> value) {
086      super(name, value);
087      this.value = null;
088      supplier = value;
089   }
090
091   /**
092    * Provides the ability to perform fluent-style assertions on this part.
093    *
094    * @return A new fluent assertion object.
095    * @throws AssertionError If assertion failed.
096    */
097   public FluentStringAssertion<BasicStringPart> assertString() {
098      return new FluentStringAssertion<>(value(), this);
099   }
100
101   /**
102    * Returns The part value as a {@link String} wrapped in an {@link Optional}.
103    *
104    * @return The part value as a {@link String} wrapped in an {@link Optional}.  Never <jk>null</jk>.
105    */
106   public Optional<String> asString() {
107      return opt(value());
108   }
109
110   @Override /* Overridden from Header */
111   public String getValue() { return value(); }
112
113   /**
114    * Return the value if present, otherwise return <c>other</c>.
115    *
116    * <p>
117    * This is a shortened form for calling <c>asString().orElse(<jv>other</jv>)</c>.
118    *
119    * @param other The value to be returned if there is no value present, can be <jk>null</jk>.
120    * @return The value, if present, otherwise <c>other</c>.
121    */
122   public String orElse(String other) {
123      String x = value();
124      return nn(x) ? x : other;
125   }
126
127   private String value() {
128      if (nn(supplier))
129         return supplier.get();
130      return value;
131   }
132}