Source code

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.uon;
014
015import java.io.*;
016
017import org.apache.juneau.*;
018import org.apache.juneau.internal.*;
019import org.apache.juneau.serializer.*;
020
021/**
022 * Specialized writer for serializing UON-encoded text.
023 *
024 * <ul class='notes'>
025 *    <li>
026 *       This class is not intended for external use.
027 * </ul>
028 */
029public final class UonWriter extends SerializerWriter {
030
031   private final UonSerializerSession session;
032   private final boolean encodeChars, plainTextParams;
033
034   // Characters that do not need to be URL-encoded in strings.
035   private static final AsciiSet unencodedChars = AsciiSet.create().ranges("a-z","A-Z","0-9").chars(";/?:@-_.!*'$(),~=").build();
036
037   // Characters that do not need to be URL-encoded in attribute names.
038   // Identical to unencodedChars, but excludes '='.
039   private static final AsciiSet unencodedCharsAttrName = AsciiSet.create().ranges("a-z","A-Z","0-9").chars(";/?:@-_.!*'$(),~").build();
040
041   // Characters that need to be preceded with an escape character.
042   private static final AsciiSet escapedChars = AsciiSet.create("~'");
043
044   private static final AsciiSet noChars = AsciiSet.create("");
045
046   private static char[] hexArray = "0123456789ABCDEF".toCharArray();
047
048   /**
049    * Constructor.
050    *
051    * @param session The session that created this writer.
052    * @param out The writer being wrapped.
053    * @param useWhitespace If <jk>true</jk>, tabs will be used in output.
054    * @param maxIndent The maximum indentation level.
055    * @param encodeChars If <jk>true</jk>, special characters should be encoded.
056    * @param trimStrings If <jk>true</jk>, strings should be trimmed before they're serialized.
057    * @param plainTextParams If <jk>true</jk>, don't use UON notation for values.
058    * @param uriResolver The URI resolver for resolving URIs to absolute or root-relative form.
059    */
060   protected UonWriter(UonSerializerSession session, Writer out, boolean useWhitespace, int maxIndent,
061         boolean encodeChars, boolean trimStrings, boolean plainTextParams, UriResolver uriResolver) {
062      super(out, useWhitespace, maxIndent, trimStrings, '\'', uriResolver);
063      this.session = session;
064      this.encodeChars = encodeChars;
065      this.plainTextParams = plainTextParams;
066   }
067
068   /**
069    * Serializes the specified simple object as a UON string value.
070    *
071    * @param o The object being serialized.
072    * @param isTopAttrName If this is a top-level attribute name we're serializing.
073    * @return This object (for method chaining).
074    * @throws IOException Should never happen.
075    */
076   public final UonWriter appendObject(Object o, boolean isTopAttrName) throws IOException {
077
078      if (o instanceof Boolean)
079         return appendBoolean(o);
080      if (o instanceof Number)
081         return appendNumber(o);
082      if (o == null)
083         return append("null");
084
085      String s = session.toString(o);
086
087      boolean needsQuotes = (! plainTextParams) && UonUtils.needsQuotes(s);
088
089      AsciiSet unenc = (isTopAttrName ? unencodedCharsAttrName : unencodedChars);
090      AsciiSet esc = plainTextParams ? noChars : escapedChars;
091
092      if (needsQuotes)
093         append('\'');
094      for (int i = 0; i < s.length(); i++) {
095         char c = s.charAt(i);
096         if (esc.contains(c))
097            append('~');
098         if ((!encodeChars) || unenc.contains(c))
099            append(c);
100         else {
101            if (c == ' ')
102               append('+');
103            else {
104               int p = s.codePointAt(i);
105               if (p < 0x0080)
106                  appendHex(p);
107               else if (p < 0x0800) {
108                  int p1=p>>>6;
109                  appendHex(p1+192).appendHex((p&63)+128);
110               } else if (p < 0x10000) {
111                  int p1=p>>>6, p2=p1>>>6;
112                  appendHex(p2+224).appendHex((p1&63)+128).appendHex((p&63)+128);
113               } else {
114                  i++;  // Two-byte codepoint...skip past surrogate pair lower byte.
115                  int p1=p>>>6, p2=p1>>>6, p3=p2>>>6;
116                  appendHex(p3+240).appendHex((p2&63)+128).appendHex((p1&63)+128).appendHex((p&63)+128);
117               }
118            }
119         }
120      }
121      if (needsQuotes)
122         append('\'');
123
124      return this;
125   }
126
127   /**
128    * Appends a boolean value to the output.
129    *
130    * @param o The boolean value to append to the output.
131    * @return This object (for method chaining).
132    * @throws IOException Thrown by underlying stream.
133    */
134   protected UonWriter appendBoolean(Object o) throws IOException {
135      append(o.toString());
136      return this;
137   }
138
139   /**
140    * Appends a numeric value to the output.
141    *
142    * @param o The numeric value to append to the output.
143    * @return This object (for method chaining).
144    * @throws IOException Thrown by underlying stream.
145    */
146   protected UonWriter appendNumber(Object o) throws IOException {
147      append(o.toString());
148      return this;
149   }
150
151   /**
152    * Prints out a two-byte %xx sequence for the given byte value.
153    */
154   private UonWriter appendHex(int b) throws IOException {
155      if (b > 255)
156         throw new IOException("Invalid value passed to appendHex.  Must be in the range 0-255.  Value=" + b);
157      append('%').append(hexArray[b>>>4]).append(hexArray[b&0x0F]);
158      return this;
159   }
160
161   /**
162    * Appends a URI to the output.
163    *
164    * @param uri The URI to append to the output.
165    * @return This object (for method chaining).
166    * @throws IOException Thrown by underlying stream.
167    */
168   @Override
169   public SerializerWriter appendUri(Object uri) throws IOException {
170      return appendObject(uriResolver.resolve(uri), false);
171   }
172
173
174   //-----------------------------------------------------------------------------------------------------------------
175   // Overridden methods
176   //-----------------------------------------------------------------------------------------------------------------
177
178   @Override /* SerializerWriter */
179   public UonWriter cr(int depth) throws IOException {
180      super.cr(depth);
181      return this;
182   }
183
184   @Override /* SerializerWriter */
185   public UonWriter cre(int depth) throws IOException {
186      super.cre(depth);
187      return this;
188   }
189
190   @Override /* SerializerWriter */
191   public UonWriter appendln(int indent, String text) throws IOException {
192      super.appendln(indent, text);
193      return this;
194   }
195
196   @Override /* SerializerWriter */
197   public UonWriter appendln(String text) throws IOException {
198      super.appendln(text);
199      return this;
200   }
201
202   @Override /* SerializerWriter */
203   public UonWriter append(int indent, String text) throws IOException {
204      super.append(indent, text);
205      return this;
206   }
207
208   @Override /* SerializerWriter */
209   public UonWriter append(int indent, char c) throws IOException {
210      super.append(indent, c);
211      return this;
212   }
213
214   @Override /* SerializerWriter */
215   public UonWriter q() throws IOException {
216      super.q();
217      return this;
218   }
219
220   @Override /* SerializerWriter */
221   public UonWriter i(int indent) throws IOException {
222      super.i(indent);
223      return this;
224   }
225
226   @Override /* SerializerWriter */
227   public UonWriter nl(int indent) throws IOException {
228      super.nl(indent);
229      return this;
230   }
231
232   @Override /* SerializerWriter */
233   public UonWriter append(Object text) throws IOException {
234      super.append(text);
235      return this;
236   }
237
238   @Override /* SerializerWriter */
239   public UonWriter append(String text) throws IOException {
240      super.append(text);
241      return this;
242   }
243
244   @Override /* SerializerWriter */
245   public UonWriter appendIf(boolean b, String text) throws IOException {
246      super.appendIf(b, text);
247      return this;
248   }
249
250   @Override /* SerializerWriter */
251   public UonWriter appendIf(boolean b, char c) throws IOException {
252      super.appendIf(b, c);
253      return this;
254   }
255
256   @Override /* SerializerWriter */
257   public UonWriter append(char c) throws IOException {
258      super.append(c);
259      return this;
260   }
261}