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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *   https://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing,
13   * software distributed under the License is distributed on an
14   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15   * KIND, either express or implied.  See the License for the
16   * specific language governing permissions and limitations
17   * under the License.
18   */
19  package org.apache.bcel.util;
20  
21  import java.io.File;
22  import java.io.FileNotFoundException;
23  import java.io.IOException;
24  import java.io.PrintWriter;
25  import java.io.UnsupportedEncodingException;
26  import java.nio.charset.Charset;
27  import java.nio.charset.StandardCharsets;
28  import java.util.HashSet;
29  import java.util.Set;
30  
31  import org.apache.bcel.Const;
32  import org.apache.bcel.Constants;
33  import org.apache.bcel.classfile.Attribute;
34  import org.apache.bcel.classfile.ClassParser;
35  import org.apache.bcel.classfile.ConstantPool;
36  import org.apache.bcel.classfile.JavaClass;
37  import org.apache.bcel.classfile.Method;
38  import org.apache.bcel.classfile.Utility;
39  
40  /**
41   * Read class file(s) and convert them into HTML files.
42   *
43   * Given a JavaClass object "class" that is in package "package" five files will be created in the specified directory.
44   *
45   * <OL>
46   * <LI>"package"."class".html as the main file which defines the frames for the following subfiles.
47   * <LI>"package"."class"_attributes.html contains all (known) attributes found in the file
48   * <LI>"package"."class"_cp.html contains the constant pool
49   * <LI>"package"."class"_code.html contains the byte code
50   * <LI>"package"."class"_methods.html contains references to all methods and fields of the class
51   * </OL>
52   *
53   * All subfiles reference each other appropriately, for example clicking on a method in the Method's frame will jump to the
54   * appropriate method in the Code frame.
55   */
56  public class Class2HTML implements Constants {
57  
58      private static String classPackage; // name of package, unclean to make it static, but ...
59      private static String className; // name of current class, dito
60      private static ConstantPool constantPool;
61      private static final Set<String> basicTypes = new HashSet<>();
62      static {
63          basicTypes.add("int");
64          basicTypes.add("short");
65          basicTypes.add("boolean");
66          basicTypes.add("void");
67          basicTypes.add("char");
68          basicTypes.add("byte");
69          basicTypes.add("long");
70          basicTypes.add("double");
71          basicTypes.add("float");
72      }
73  
74      /**
75       * Main program to convert class files to HTML.
76       *
77       * @param argv command line arguments.
78       * @throws IOException if an I/O error occurs.
79       */
80      public static void main(final String[] argv) throws IOException {
81          final String[] fileName = new String[argv.length];
82          int files = 0;
83          ClassParser parser = null;
84          JavaClass javaClass = null;
85          String zipFile = null;
86          final char sep = File.separatorChar;
87          String dir = "." + sep; // Where to store HTML files
88          /*
89           * Parse command line arguments.
90           */
91          for (int i = 0; i < argv.length; i++) {
92              if (argv[i].charAt(0) == '-') { // command line switch
93                  if (argv[i].equals("-d")) { // Specify target directory, default '.'
94                      dir = argv[++i];
95                      if (!dir.endsWith("" + sep)) {
96                          dir += sep;
97                      }
98                      final File store = new File(dir);
99                      if (!store.isDirectory()) {
100                         final boolean created = store.mkdirs(); // Create target directory if necessary
101                         if (!created && !store.isDirectory()) {
102                             System.out.println("Tried to create the directory " + dir + " but failed");
103                         }
104                     }
105                 } else if (argv[i].equals("-zip")) {
106                     zipFile = argv[++i];
107                 } else {
108                     System.out.println("Unknown option " + argv[i]);
109                 }
110             } else {
111                 fileName[files++] = argv[i];
112             }
113         }
114         if (files == 0) {
115             System.err.println("Class2HTML: No input files specified.");
116         } else { // Loop through files ...
117             for (int i = 0; i < files; i++) {
118                 System.out.print("Processing " + fileName[i] + "...");
119                 if (zipFile == null) {
120                     parser = new ClassParser(fileName[i]); // Create parser object from file
121                 } else {
122                     parser = new ClassParser(zipFile, fileName[i]); // Create parser object from ZIP file
123                 }
124                 javaClass = parser.parse();
125                 new Class2HTML(javaClass, dir);
126                 System.out.println("Done.");
127             }
128         }
129     }
130 
131     /**
132      * Utility method that converts a class reference in the constant pool, that is, an index to a string.
133      */
134     static String referenceClass(final int index) {
135         String str = constantPool.getConstantString(index, Const.CONSTANT_Class);
136         str = Utility.compactClassName(str);
137         str = Utility.compactClassName(str, classPackage + ".", true);
138         return "<A HREF=\"" + className + "_cp.html#cp" + index + "\" TARGET=ConstantPool>" + str + "</A>";
139     }
140 
141     static String referenceType(final String type) {
142         String shortType = Utility.compactClassName(type);
143         shortType = Utility.compactClassName(shortType, classPackage + ".", true);
144         final int index = type.indexOf('['); // Type is an array?
145         String baseType = type;
146         if (index > -1) {
147             baseType = type.substring(0, index); // Tack of the '['
148         }
149         // test for basic type
150         if (basicTypes.contains(baseType)) {
151             return "<FONT COLOR=\"#00FF00\">" + type + "</FONT>";
152         }
153         return "<A HREF=\"" + baseType + ".html\" TARGET=_top>" + shortType + "</A>";
154     }
155 
156     static String toHTML(final String str) {
157         final StringBuilder buf = new StringBuilder();
158         for (int i = 0; i < str.length(); i++) {
159             final char ch;
160             switch (ch = str.charAt(i)) {
161             case '<':
162                 buf.append("&lt;");
163                 break;
164             case '>':
165                 buf.append("&gt;");
166                 break;
167             case '\n':
168                 buf.append("\\n");
169                 break;
170             case '\r':
171                 buf.append("\\r");
172                 break;
173             default:
174                 buf.append(ch);
175             }
176         }
177         return buf.toString();
178     }
179 
180     private final JavaClass javaClass; // current class object
181 
182     private final String dir;
183 
184     /**
185      * Writes contents of the given JavaClass into HTML files.
186      *
187      * @param javaClass The class to write.
188      * @param dir The directory to put the files in.
189      * @throws IOException Thrown when an I/O exception of some sort has occurred.
190      */
191     public Class2HTML(final JavaClass javaClass, final String dir) throws IOException {
192         this(javaClass, dir, StandardCharsets.UTF_8);
193     }
194 
195     private Class2HTML(final JavaClass javaClass, final String dir, final Charset charset) throws IOException {
196         final Method[] methods = javaClass.getMethods();
197         this.javaClass = javaClass;
198         this.dir = dir;
199         className = javaClass.getClassName(); // Remember full name
200         constantPool = javaClass.getConstantPool();
201         // Get package name by tacking off everything after the last '.'
202         final int index = className.lastIndexOf('.');
203         if (index > -1) {
204             classPackage = className.substring(0, index);
205         } else {
206             classPackage = ""; // default package
207         }
208         final ConstantHTML constantHtml = new ConstantHTML(dir, className, classPackage, methods, constantPool, charset);
209         /*
210          * Attributes can't be written in one step, so we just open a file which will be written consequently.
211          */
212         try (AttributeHTML attributeHtml = new AttributeHTML(dir, className, constantPool, constantHtml, charset)) {
213             new MethodHTML(dir, className, methods, javaClass.getFields(), constantHtml, attributeHtml, charset);
214             // Write main file (with frames, yuk)
215             writeMainHTML(attributeHtml, charset);
216             new CodeHTML(dir, className, methods, constantPool, constantHtml, charset);
217         }
218     }
219 
220     private void writeMainHTML(final AttributeHTML attributeHtml, final Charset charset) throws FileNotFoundException, UnsupportedEncodingException {
221         try (PrintWriter file = new PrintWriter(dir + className + ".html", charset.name())) {
222             // @formatter:off
223             file.println("<HTML>\n"
224                 + "<HEAD><TITLE>Documentation for " + className + "</TITLE></HEAD>\n"
225                 + "<FRAMESET BORDER=1 cols=\"30%,*\">\n"
226                 + "<FRAMESET BORDER=1 rows=\"80%,*\">\n"
227                 + "<FRAME NAME=\"ConstantPool\" SRC=\"" + className + "_cp.html" + "\"\n"
228                 + "MARGINWIDTH=\"0\" "
229                 + "MARGINHEIGHT=\"0\" FRAMEBORDER=\"1\" SCROLLING=\"AUTO\">\n"
230                 + "<FRAME NAME=\"Attributes\" SRC=\"" + className + "_attributes.html\"\n"
231                 + " MARGINWIDTH=\"0\" MARGINHEIGHT=\"0\" FRAMEBORDER=\"1\" SCROLLING=\"AUTO\">\n"
232                 + "</FRAMESET>\n"
233                 + "<FRAMESET BORDER=1 rows=\"80%,*\">\n"
234                 + "<FRAME NAME=\"Code\" SRC=\"" + className + "_code.html\"\n"
235                 + " MARGINWIDTH=0 "
236                 + "MARGINHEIGHT=0 FRAMEBORDER=1 SCROLLING=\"AUTO\">\n"
237                 + "<FRAME NAME=\"Methods\" SRC=\"" + className + "_methods.html\"\n"
238                 + " MARGINWIDTH=0 "
239                 + "MARGINHEIGHT=0 FRAMEBORDER=1 SCROLLING=\"AUTO\">\n"
240                 + "</FRAMESET></FRAMESET></HTML>");
241             // @formatter:on
242         }
243         final Attribute[] attributes = javaClass.getAttributes();
244         for (int i = 0; i < attributes.length; i++) {
245             attributeHtml.writeAttribute(attributes[i], "class" + i);
246         }
247     }
248 }