001////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code for adherence to a set of rules.
003// Copyright (C) 2001-2020 the original author or authors.
004//
005// This library is free software; you can redistribute it and/or
006// modify it under the terms of the GNU Lesser General Public
007// License as published by the Free Software Foundation; either
008// version 2.1 of the License, or (at your option) any later version.
009//
010// This library is distributed in the hope that it will be useful,
011// but WITHOUT ANY WARRANTY; without even the implied warranty of
012// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
013// Lesser General Public License for more details.
014//
015// You should have received a copy of the GNU Lesser General Public
016// License along with this library; if not, write to the Free Software
017// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
018////////////////////////////////////////////////////////////////////////////////
019
020package com.puppycrawl.tools.checkstyle;
021
022import java.io.File;
023import java.io.IOException;
024import java.nio.charset.StandardCharsets;
025
026import com.puppycrawl.tools.checkstyle.JavadocDetailNodeParser.ParseErrorMessage;
027import com.puppycrawl.tools.checkstyle.JavadocDetailNodeParser.ParseStatus;
028import com.puppycrawl.tools.checkstyle.api.DetailAST;
029import com.puppycrawl.tools.checkstyle.api.DetailNode;
030import com.puppycrawl.tools.checkstyle.api.FileText;
031import com.puppycrawl.tools.checkstyle.api.JavadocTokenTypes;
032import com.puppycrawl.tools.checkstyle.api.LocalizedMessage;
033import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
034import com.puppycrawl.tools.checkstyle.utils.JavadocUtil;
035
036/**
037 * Parses file as javadoc DetailNode tree and prints to system output stream.
038 */
039public final class DetailNodeTreeStringPrinter {
040
041    /** OS specific line separator. */
042    private static final String LINE_SEPARATOR = System.getProperty("line.separator");
043
044    /** Prevent instances. */
045    private DetailNodeTreeStringPrinter() {
046        // no code
047    }
048
049    /**
050     * Parse a file and print the parse tree.
051     *
052     * @param file the file to print.
053     * @return parse tree as a string
054     * @throws IOException if the file could not be read.
055     */
056    public static String printFileAst(File file) throws IOException {
057        return printTree(parseFile(file), "", "");
058    }
059
060    /**
061     * Parse block comment DetailAST as Javadoc DetailNode tree.
062     *
063     * @param blockComment DetailAST
064     * @return DetailNode tree
065     */
066    public static DetailNode parseJavadocAsDetailNode(DetailAST blockComment) {
067        final JavadocDetailNodeParser parser = new JavadocDetailNodeParser();
068        final ParseStatus status = parser.parseJavadocAsDetailNode(blockComment);
069        if (status.getParseErrorMessage() != null) {
070            throw new IllegalArgumentException(getParseErrorMessage(status.getParseErrorMessage()));
071        }
072        return status.getTree();
073    }
074
075    /**
076     * Parse javadoc comment to DetailNode tree.
077     *
078     * @param javadocComment javadoc comment content
079     * @return tree
080     */
081    private static DetailNode parseJavadocAsDetailNode(String javadocComment) {
082        final DetailAST blockComment = CommonUtil.createBlockCommentNode(javadocComment);
083        return parseJavadocAsDetailNode(blockComment);
084    }
085
086    /**
087     * Builds error message base on ParseErrorMessage's message key, its arguments, etc.
088     *
089     * @param parseErrorMessage ParseErrorMessage
090     * @return error message
091     */
092    private static String getParseErrorMessage(ParseErrorMessage parseErrorMessage) {
093        final LocalizedMessage lmessage = new LocalizedMessage(
094                parseErrorMessage.getLineNumber(),
095                "com.puppycrawl.tools.checkstyle.checks.javadoc.messages",
096                parseErrorMessage.getMessageKey(),
097                parseErrorMessage.getMessageArguments(),
098                "",
099                DetailNodeTreeStringPrinter.class,
100                null);
101        return "[ERROR:" + parseErrorMessage.getLineNumber() + "] " + lmessage.getMessage();
102    }
103
104    /**
105     * Print AST.
106     *
107     * @param ast the root AST node.
108     * @param rootPrefix prefix for the root node
109     * @param prefix prefix for other nodes
110     * @return string AST.
111     */
112    public static String printTree(DetailNode ast, String rootPrefix, String prefix) {
113        final StringBuilder messageBuilder = new StringBuilder(1024);
114        DetailNode node = ast;
115        while (node != null) {
116            if (node.getType() == JavadocTokenTypes.JAVADOC) {
117                messageBuilder.append(rootPrefix);
118            }
119            else {
120                messageBuilder.append(prefix);
121            }
122            messageBuilder.append(getIndentation(node))
123                    .append(JavadocUtil.getTokenName(node.getType())).append(" -> ")
124                    .append(JavadocUtil.escapeAllControlChars(node.getText())).append(" [")
125                    .append(node.getLineNumber()).append(':').append(node.getColumnNumber())
126                    .append(']').append(LINE_SEPARATOR)
127                    .append(printTree(JavadocUtil.getFirstChild(node), rootPrefix, prefix));
128            node = JavadocUtil.getNextSibling(node);
129        }
130        return messageBuilder.toString();
131    }
132
133    /**
134     * Get indentation for a node.
135     *
136     * @param node the DetailNode to get the indentation for.
137     * @return the indentation in String format.
138     */
139    private static String getIndentation(DetailNode node) {
140        final boolean isLastChild = JavadocUtil.getNextSibling(node) == null;
141        DetailNode currentNode = node;
142        final StringBuilder indentation = new StringBuilder(1024);
143        while (currentNode.getParent() != null) {
144            currentNode = currentNode.getParent();
145            if (currentNode.getParent() == null) {
146                if (isLastChild) {
147                    // only ASCII symbols must be used due to
148                    // problems with running tests on Windows
149                    indentation.append("`--");
150                }
151                else {
152                    indentation.append("|--");
153                }
154            }
155            else {
156                if (JavadocUtil.getNextSibling(currentNode) == null) {
157                    indentation.insert(0, "    ");
158                }
159                else {
160                    indentation.insert(0, "|   ");
161                }
162            }
163        }
164        return indentation.toString();
165    }
166
167    /**
168     * Parse a file and return the parse tree.
169     *
170     * @param file the file to parse.
171     * @return the root node of the parse tree.
172     * @throws IOException if the file could not be read.
173     */
174    private static DetailNode parseFile(File file) throws IOException {
175        final FileText text = new FileText(file.getAbsoluteFile(),
176            System.getProperty("file.encoding", StandardCharsets.UTF_8.name()));
177        return parseJavadocAsDetailNode(text.getFullText().toString());
178    }
179
180}