View Javadoc
1   ///////////////////////////////////////////////////////////////////////////////////////////////
2   // checkstyle: Checks Java source code and other text files for adherence to a set of rules.
3   // Copyright (C) 2001-2024 the original author or authors.
4   //
5   // This library is free software; you can redistribute it and/or
6   // modify it under the terms of the GNU Lesser General Public
7   // License as published by the Free Software Foundation; either
8   // version 2.1 of the License, or (at your option) any later version.
9   //
10  // This library is distributed in the hope that it will be useful,
11  // but WITHOUT ANY WARRANTY; without even the implied warranty of
12  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  // Lesser General Public License for more details.
14  //
15  // You should have received a copy of the GNU Lesser General Public
16  // License along with this library; if not, write to the Free Software
17  // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18  ///////////////////////////////////////////////////////////////////////////////////////////////
19  
20  package com.puppycrawl.tools.checkstyle;
21  
22  import java.io.File;
23  import java.io.IOException;
24  import java.nio.charset.StandardCharsets;
25  
26  import com.puppycrawl.tools.checkstyle.JavadocDetailNodeParser.ParseErrorMessage;
27  import com.puppycrawl.tools.checkstyle.JavadocDetailNodeParser.ParseStatus;
28  import com.puppycrawl.tools.checkstyle.api.DetailAST;
29  import com.puppycrawl.tools.checkstyle.api.DetailNode;
30  import com.puppycrawl.tools.checkstyle.api.FileText;
31  import com.puppycrawl.tools.checkstyle.api.JavadocTokenTypes;
32  import com.puppycrawl.tools.checkstyle.utils.JavadocUtil;
33  import com.puppycrawl.tools.checkstyle.utils.ParserUtil;
34  
35  /**
36   * Parses file as javadoc DetailNode tree and prints to system output stream.
37   */
38  public final class DetailNodeTreeStringPrinter {
39  
40      /** OS specific line separator. */
41      private static final String LINE_SEPARATOR = System.getProperty("line.separator");
42  
43      /** Prevent instances. */
44      private DetailNodeTreeStringPrinter() {
45          // no code
46      }
47  
48      /**
49       * Parse a file and print the parse tree.
50       *
51       * @param file the file to print.
52       * @return parse tree as a string
53       * @throws IOException if the file could not be read.
54       */
55      public static String printFileAst(File file) throws IOException {
56          return printTree(parseFile(file), "", "");
57      }
58  
59      /**
60       * Parse block comment DetailAST as Javadoc DetailNode tree.
61       *
62       * @param blockComment DetailAST
63       * @return DetailNode tree
64       * @throws IllegalArgumentException if there is an error parsing the Javadoc.
65       */
66      public static DetailNode parseJavadocAsDetailNode(DetailAST blockComment) {
67          final JavadocDetailNodeParser parser = new JavadocDetailNodeParser();
68          final ParseStatus status = parser.parseJavadocAsDetailNode(blockComment);
69          if (status.getParseErrorMessage() != null) {
70              throw new IllegalArgumentException(getParseErrorMessage(status.getParseErrorMessage()));
71          }
72          return status.getTree();
73      }
74  
75      /**
76       * Parse javadoc comment to DetailNode tree.
77       *
78       * @param javadocComment javadoc comment content
79       * @return tree
80       */
81      private static DetailNode parseJavadocAsDetailNode(String javadocComment) {
82          final DetailAST blockComment = ParserUtil.createBlockCommentNode(javadocComment);
83          return parseJavadocAsDetailNode(blockComment);
84      }
85  
86      /**
87       * Builds violation base on ParseErrorMessage's violation key, its arguments, etc.
88       *
89       * @param parseErrorMessage ParseErrorMessage
90       * @return error violation
91       */
92      private static String getParseErrorMessage(ParseErrorMessage parseErrorMessage) {
93          final LocalizedMessage message = new LocalizedMessage(
94                  "com.puppycrawl.tools.checkstyle.checks.javadoc.messages",
95                  DetailNodeTreeStringPrinter.class,
96                  parseErrorMessage.getMessageKey(),
97                  parseErrorMessage.getMessageArguments());
98          return "[ERROR:" + parseErrorMessage.getLineNumber() + "] " + message.getMessage();
99      }
100 
101     /**
102      * Print AST.
103      *
104      * @param ast the root AST node.
105      * @param rootPrefix prefix for the root node
106      * @param prefix prefix for other nodes
107      * @return string AST.
108      */
109     public static String printTree(DetailNode ast, String rootPrefix, String prefix) {
110         final StringBuilder messageBuilder = new StringBuilder(1024);
111         DetailNode node = ast;
112         while (node != null) {
113             if (node.getType() == JavadocTokenTypes.JAVADOC) {
114                 messageBuilder.append(rootPrefix);
115             }
116             else {
117                 messageBuilder.append(prefix);
118             }
119             messageBuilder.append(getIndentation(node))
120                     .append(JavadocUtil.getTokenName(node.getType())).append(" -> ")
121                     .append(JavadocUtil.escapeAllControlChars(node.getText())).append(" [")
122                     .append(node.getLineNumber()).append(':').append(node.getColumnNumber())
123                     .append(']').append(LINE_SEPARATOR)
124                     .append(printTree(JavadocUtil.getFirstChild(node), rootPrefix, prefix));
125             node = JavadocUtil.getNextSibling(node);
126         }
127         return messageBuilder.toString();
128     }
129 
130     /**
131      * Get indentation for a node.
132      *
133      * @param node the DetailNode to get the indentation for.
134      * @return the indentation in String format.
135      */
136     private static String getIndentation(DetailNode node) {
137         final boolean isLastChild = JavadocUtil.getNextSibling(node) == null;
138         DetailNode currentNode = node;
139         final StringBuilder indentation = new StringBuilder(1024);
140         while (currentNode.getParent() != null) {
141             currentNode = currentNode.getParent();
142             if (currentNode.getParent() == null) {
143                 if (isLastChild) {
144                     // only ASCII symbols must be used due to
145                     // problems with running tests on Windows
146                     indentation.append("`--");
147                 }
148                 else {
149                     indentation.append("|--");
150                 }
151             }
152             else {
153                 if (JavadocUtil.getNextSibling(currentNode) == null) {
154                     indentation.insert(0, "    ");
155                 }
156                 else {
157                     indentation.insert(0, "|   ");
158                 }
159             }
160         }
161         return indentation.toString();
162     }
163 
164     /**
165      * Parse a file and return the parse tree.
166      *
167      * @param file the file to parse.
168      * @return the root node of the parse tree.
169      * @throws IOException if the file could not be read.
170      */
171     private static DetailNode parseFile(File file) throws IOException {
172         final FileText text = new FileText(file.getAbsoluteFile(),
173             System.getProperty("file.encoding", StandardCharsets.UTF_8.name()));
174         return parseJavadocAsDetailNode(text.getFullText().toString());
175     }
176 
177 }