View Javadoc
1   package org.apache.maven.jxr.pacman;
2   
3   /*
4    * Licensed to the Apache Software Foundation (ASF) under one
5    * or more contributor license agreements.  See the NOTICE file
6    * distributed with this work for additional information
7    * regarding copyright ownership.  The ASF licenses this file
8    * to you under the Apache License, Version 2.0 (the
9    * "License"); you may not use this file except in compliance
10   * with the License.  You may obtain a copy of the License at
11   *
12   *   http://www.apache.org/licenses/LICENSE-2.0
13   *
14   * Unless required by applicable law or agreed to in writing,
15   * software distributed under the License is distributed on an
16   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17   * KIND, either express or implied.  See the License for the
18   * specific language governing permissions and limitations
19   * under the License.
20   */
21  
22  import java.io.FileInputStream;
23  import java.io.FileReader;
24  import java.io.IOException;
25  import java.io.InputStreamReader;
26  import java.io.Reader;
27  import java.io.StreamTokenizer;
28  import java.nio.file.Files;
29  import java.nio.file.Path;
30  
31  /**
32   * PacMan implementation of a JavaFile. This will parse out the file and
33   * determine package, class, and imports
34   *
35   * @author <a href="mailto:burton@apache.org">Kevin A. Burton</a>
36   * @version $Id$
37   */
38  public class JavaFileImpl
39      extends JavaFile
40  {
41      /**
42       * Create a new JavaFileImpl that points to a given file...
43       *
44       * @param path
45       * @param encoding
46       * @throws IOException
47       */
48      public JavaFileImpl( Path path, String encoding )
49          throws IOException
50      {
51          super( path, encoding );
52  
53          //always add java.lang.* to the package imports because the JVM always
54          //does this implicitly.  Unless we add this to the ImportTypes JXR
55          //won't pick up on this.
56          this.addImportType( new ImportType( "java.lang.*" ) );
57  
58          //now parse out this file.
59          this.parse();
60      }
61  
62      /**
63       * Open up the file and try to determine package, class and import
64       * statements.
65       */
66      private void parse()
67          throws IOException
68      {
69          StreamTokenizer stok = null;
70          try ( Reader reader = getReader() )
71          {
72              stok = this.getTokenizer( reader );
73  
74              parseRecursive( "", stok );
75          }
76          finally
77          {
78              stok = null;
79          }
80      }
81  
82      private void parseRecursive( String nestedPrefix, StreamTokenizer stok )
83              throws IOException
84      {
85          int openBracesCount = 0;
86  
87          while ( stok.nextToken() != StreamTokenizer.TT_EOF )
88          {
89  
90              if ( stok.sval == null )
91              {
92                  if ( stok.ttype == '{' )
93                  {
94                      openBracesCount++;
95                  }
96                  else if ( stok.ttype == '}' )
97                  {
98                      if ( --openBracesCount == 0 )
99                      {
100                         // break out of recursive
101                         return;
102                     }
103                 }
104                 continue;
105             }
106 
107             //set the package
108             if ( "package".equals( stok.sval ) && stok.ttype != '\"' )
109             {
110                 stok.nextToken();
111                 this.setPackageType( new PackageType( stok.sval ) );
112             }
113 
114             //set the imports
115             if ( "import".equals( stok.sval )  && stok.ttype != '\"' )
116             {
117                 stok.nextToken();
118 
119                 String name = stok.sval;
120 
121                 /*
122                 WARNING: this is a bug/non-feature in the current
123                 StreamTokenizer.  We needed to set the comment char as "*"
124                 and packages that are imported with this (ex "test.*") will be
125                 stripped( and become "test." ).  Here we need to test for this
126                 and if necessary re-add the char.
127                 */
128                 if ( name.charAt( name.length() - 1 ) == '.' )
129                 {
130                     name = name + '*';
131                 }
132 
133                 this.addImportType( new ImportType( name ) );
134             }
135 
136             // Add the class or classes. There can be several classes in one file so
137             // continue with the while loop to get them all.
138             if ( ( "class".equals( stok.sval ) || "interface".equals( stok.sval ) || "enum".equals( stok.sval ) )
139                     &&  stok.ttype != '\"' )
140             {
141                 stok.nextToken();
142                 this.addClassType( new ClassType( nestedPrefix + stok.sval,
143                         getFilenameWithoutPathOrExtension( this.getPath() ) ) );
144                 parseRecursive( nestedPrefix + stok.sval + ".", stok );
145             }
146 
147         }
148     }
149 
150     /**
151      * Remove the path and the ".java" extension from a filename.
152      */
153     private static String getFilenameWithoutPathOrExtension( Path path )
154     {
155         String newFilename = path.getFileName().toString();
156         // Remove the ".java" extension from the filename, if it exists
157         int extensionIndex = newFilename.lastIndexOf( ".java" );
158         if ( extensionIndex >= 0 )
159         {
160             newFilename = newFilename.substring( 0, extensionIndex );
161         }
162         return newFilename;
163     }
164 
165     /**
166      * Get a StreamTokenizer for this file.
167      */
168     private StreamTokenizer getTokenizer( Reader reader )
169     {
170         StreamTokenizer stok = new StreamTokenizer( reader );
171         //int tok;
172 
173         stok.commentChar( '*' );
174         stok.wordChars( '_', '_' );
175 
176         // set tokenizer to skip comments
177         stok.slashStarComments( true );
178         stok.slashSlashComments( true );
179 
180         return stok;
181     }
182     
183     private Reader getReader()
184         throws IOException
185     {
186         if ( Files.notExists( this.getPath() ) )
187         {
188             throw new IOException( this.getPath() + " does not exist!" );
189         }
190 
191         if ( this.getEncoding() != null )
192         {
193             return new InputStreamReader( new FileInputStream( this.getPath().toFile() ), this.getEncoding() );
194         }
195         else
196         {
197             return new FileReader( this.getPath().toFile() );
198         }
199     }    
200 }