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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.checks.indentation;
21  
22  import java.util.Collection;
23  import java.util.Iterator;
24  import java.util.NavigableMap;
25  import java.util.TreeMap;
26  
27  import com.puppycrawl.tools.checkstyle.api.DetailAST;
28  import com.puppycrawl.tools.checkstyle.api.TokenTypes;
29  import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
30  import com.puppycrawl.tools.checkstyle.utils.TokenUtil;
31  
32  /**
33   * This class checks line-wrapping into definitions and expressions. The
34   * line-wrapping indentation should be not less than value of the
35   * lineWrappingIndentation parameter.
36   *
37   */
38  public class LineWrappingHandler {
39  
40      /**
41       * Enum to be used for test if first line's indentation should be checked or not.
42       */
43      public enum LineWrappingOptions {
44  
45          /**
46           * First line's indentation should NOT be checked.
47           */
48          IGNORE_FIRST_LINE,
49          /**
50           * First line's indentation should be checked.
51           */
52          NONE;
53  
54          /**
55           * Builds enum value from boolean.
56           *
57           * @param val value.
58           * @return enum instance.
59           *
60           * @noinspection BooleanParameter
61           * @noinspectionreason BooleanParameter - check property is essentially boolean
62           */
63          public static LineWrappingOptions ofBoolean(boolean val) {
64              LineWrappingOptions option = NONE;
65              if (val) {
66                  option = IGNORE_FIRST_LINE;
67              }
68              return option;
69          }
70  
71      }
72  
73      /**
74       * The list of ignored token types for being checked by lineWrapping indentation
75       * inside {@code checkIndentation()} as these tokens are checked for lineWrapping
76       * inside their dedicated handlers.
77       *
78       * @see NewHandler#getIndentImpl()
79       * @see BlockParentHandler#curlyIndent()
80       * @see ArrayInitHandler#getIndentImpl()
81       * @see CaseHandler#getIndentImpl()
82       */
83      private static final int[] IGNORED_LIST = {
84          TokenTypes.LCURLY,
85          TokenTypes.RCURLY,
86          TokenTypes.LITERAL_NEW,
87          TokenTypes.ARRAY_INIT,
88          TokenTypes.LITERAL_DEFAULT,
89          TokenTypes.LITERAL_CASE,
90      };
91  
92      /**
93       * The current instance of {@code IndentationCheck} class using this
94       * handler. This field used to get access to private fields of
95       * IndentationCheck instance.
96       */
97      private final IndentationCheck indentCheck;
98  
99      /**
100      * Sets values of class field, finds last node and calculates indentation level.
101      *
102      * @param instance
103      *            instance of IndentationCheck.
104      */
105     public LineWrappingHandler(IndentationCheck instance) {
106         indentCheck = instance;
107     }
108 
109     /**
110      * Checks line wrapping into expressions and definitions using property
111      * 'lineWrappingIndentation'.
112      *
113      * @param firstNode First node to start examining.
114      * @param lastNode Last node to examine inclusively.
115      */
116     public void checkIndentation(DetailAST firstNode, DetailAST lastNode) {
117         checkIndentation(firstNode, lastNode, indentCheck.getLineWrappingIndentation());
118     }
119 
120     /**
121      * Checks line wrapping into expressions and definitions.
122      *
123      * @param firstNode First node to start examining.
124      * @param lastNode Last node to examine inclusively.
125      * @param indentLevel Indentation all wrapped lines should use.
126      */
127     private void checkIndentation(DetailAST firstNode, DetailAST lastNode, int indentLevel) {
128         checkIndentation(firstNode, lastNode, indentLevel,
129                 -1, LineWrappingOptions.IGNORE_FIRST_LINE);
130     }
131 
132     /**
133      * Checks line wrapping into expressions and definitions.
134      *
135      * @param firstNode First node to start examining.
136      * @param lastNode Last node to examine inclusively.
137      * @param indentLevel Indentation all wrapped lines should use.
138      * @param startIndent Indentation first line before wrapped lines used.
139      * @param ignoreFirstLine Test if first line's indentation should be checked or not.
140      */
141     public void checkIndentation(DetailAST firstNode, DetailAST lastNode, int indentLevel,
142             int startIndent, LineWrappingOptions ignoreFirstLine) {
143         final NavigableMap<Integer, DetailAST> firstNodesOnLines = collectFirstNodes(firstNode,
144                 lastNode);
145 
146         final DetailAST firstLineNode = firstNodesOnLines.get(firstNodesOnLines.firstKey());
147         if (firstLineNode.getType() == TokenTypes.AT) {
148             checkForAnnotationIndentation(firstNodesOnLines, indentLevel);
149         }
150 
151         if (ignoreFirstLine == LineWrappingOptions.IGNORE_FIRST_LINE) {
152             // First node should be removed because it was already checked before.
153             firstNodesOnLines.remove(firstNodesOnLines.firstKey());
154         }
155 
156         final int firstNodeIndent;
157         if (startIndent == -1) {
158             firstNodeIndent = getLineStart(firstLineNode);
159         }
160         else {
161             firstNodeIndent = startIndent;
162         }
163         final int currentIndent = firstNodeIndent + indentLevel;
164 
165         for (DetailAST node : firstNodesOnLines.values()) {
166             final int currentType = node.getType();
167             if (checkForNullParameterChild(node) || checkForMethodLparenNewLine(node)) {
168                 continue;
169             }
170             if (currentType == TokenTypes.RPAREN) {
171                 logWarningMessage(node, firstNodeIndent);
172             }
173             else if (!TokenUtil.isOfType(currentType, IGNORED_LIST)) {
174                 logWarningMessage(node, currentIndent);
175             }
176         }
177     }
178 
179     /**
180      * Checks for annotation indentation.
181      *
182      * @param firstNodesOnLines the nodes which are present in the beginning of each line.
183      * @param indentLevel line wrapping indentation.
184      */
185     public void checkForAnnotationIndentation(
186             NavigableMap<Integer, DetailAST> firstNodesOnLines, int indentLevel) {
187         final DetailAST firstLineNode = firstNodesOnLines.get(firstNodesOnLines.firstKey());
188         DetailAST node = firstLineNode.getParent();
189         while (node != null) {
190             if (node.getType() == TokenTypes.ANNOTATION) {
191                 final DetailAST atNode = node.getFirstChild();
192                 final NavigableMap<Integer, DetailAST> annotationLines =
193                         firstNodesOnLines.subMap(
194                                 node.getLineNo(),
195                                 true,
196                                 getNextNodeLine(firstNodesOnLines, node),
197                                 true
198                         );
199                 checkAnnotationIndentation(atNode, annotationLines, indentLevel);
200             }
201             node = node.getNextSibling();
202         }
203     }
204 
205     /**
206      * Checks whether parameter node has any child or not.
207      *
208      * @param node the node for which to check.
209      * @return true if  parameter has no child.
210      */
211     public static boolean checkForNullParameterChild(DetailAST node) {
212         return node.getFirstChild() == null && node.getType() == TokenTypes.PARAMETERS;
213     }
214 
215     /**
216      * Checks whether the method lparen starts from a new line or not.
217      *
218      * @param node the node for which to check.
219      * @return true if method lparen starts from a new line.
220      */
221     public static boolean checkForMethodLparenNewLine(DetailAST node) {
222         final int parentType = node.getParent().getType();
223         return parentType == TokenTypes.METHOD_DEF && node.getType() == TokenTypes.LPAREN;
224     }
225 
226     /**
227      * Gets the next node line from the firstNodesOnLines map unless there is no next line, in
228      * which case, it returns the last line.
229      *
230      * @param firstNodesOnLines NavigableMap of lines and their first nodes.
231      * @param node the node for which to find the next node line
232      * @return the line number of the next line in the map
233      */
234     private static Integer getNextNodeLine(
235             NavigableMap<Integer, DetailAST> firstNodesOnLines, DetailAST node) {
236         Integer nextNodeLine = firstNodesOnLines.higherKey(node.getLastChild().getLineNo());
237         if (nextNodeLine == null) {
238             nextNodeLine = firstNodesOnLines.lastKey();
239         }
240         return nextNodeLine;
241     }
242 
243     /**
244      * Finds first nodes on line and puts them into Map.
245      *
246      * @param firstNode First node to start examining.
247      * @param lastNode Last node to examine inclusively.
248      * @return NavigableMap which contains lines numbers as a key and first
249      *         nodes on lines as a values.
250      */
251     private NavigableMap<Integer, DetailAST> collectFirstNodes(DetailAST firstNode,
252             DetailAST lastNode) {
253         final NavigableMap<Integer, DetailAST> result = new TreeMap<>();
254 
255         result.put(firstNode.getLineNo(), firstNode);
256         DetailAST curNode = firstNode.getFirstChild();
257 
258         while (curNode != lastNode) {
259             if (curNode.getType() == TokenTypes.OBJBLOCK
260                     || curNode.getType() == TokenTypes.SLIST) {
261                 curNode = curNode.getLastChild();
262             }
263 
264             final DetailAST firstTokenOnLine = result.get(curNode.getLineNo());
265 
266             if (firstTokenOnLine == null
267                 || expandedTabsColumnNo(firstTokenOnLine) >= expandedTabsColumnNo(curNode)) {
268                 result.put(curNode.getLineNo(), curNode);
269             }
270             curNode = getNextCurNode(curNode);
271         }
272         return result;
273     }
274 
275     /**
276      * Returns next curNode node.
277      *
278      * @param curNode current node.
279      * @return next curNode node.
280      */
281     private static DetailAST getNextCurNode(DetailAST curNode) {
282         DetailAST nodeToVisit = curNode.getFirstChild();
283         DetailAST currentNode = curNode;
284 
285         while (nodeToVisit == null) {
286             nodeToVisit = currentNode.getNextSibling();
287             if (nodeToVisit == null) {
288                 currentNode = currentNode.getParent();
289             }
290         }
291         return nodeToVisit;
292     }
293 
294     /**
295      * Checks line wrapping into annotations.
296      *
297      * @param atNode block tag node.
298      * @param firstNodesOnLines map which contains
299      *     first nodes as values and line numbers as keys.
300      * @param indentLevel line wrapping indentation.
301      */
302     private void checkAnnotationIndentation(DetailAST atNode,
303             NavigableMap<Integer, DetailAST> firstNodesOnLines, int indentLevel) {
304         final int firstNodeIndent = getLineStart(atNode);
305         final int currentIndent = firstNodeIndent + indentLevel;
306         final Collection<DetailAST> values = firstNodesOnLines.values();
307         final DetailAST lastAnnotationNode = atNode.getParent().getLastChild();
308         final int lastAnnotationLine = lastAnnotationNode.getLineNo();
309 
310         final Iterator<DetailAST> itr = values.iterator();
311         while (firstNodesOnLines.size() > 1) {
312             final DetailAST node = itr.next();
313 
314             final DetailAST parentNode = node.getParent();
315             final boolean isArrayInitPresentInAncestors =
316                 isParentContainsTokenType(node, TokenTypes.ANNOTATION_ARRAY_INIT);
317             final boolean isCurrentNodeCloseAnnotationAloneInLine =
318                 node.getLineNo() == lastAnnotationLine
319                     && isEndOfScope(lastAnnotationNode, node);
320             if (!isArrayInitPresentInAncestors
321                     && (isCurrentNodeCloseAnnotationAloneInLine
322                     || node.getType() == TokenTypes.AT
323                     && (parentNode.getParent().getType() == TokenTypes.MODIFIERS
324                         || parentNode.getParent().getType() == TokenTypes.ANNOTATIONS)
325                     || TokenUtil.areOnSameLine(node, atNode))) {
326                 logWarningMessage(node, firstNodeIndent);
327             }
328             else if (!isArrayInitPresentInAncestors) {
329                 logWarningMessage(node, currentIndent);
330             }
331             itr.remove();
332         }
333     }
334 
335     /**
336      * Checks line for end of scope.  Handles occurrences of close braces and close parenthesis on
337      * the same line.
338      *
339      * @param lastAnnotationNode the last node of the annotation
340      * @param node the node indicating where to begin checking
341      * @return true if all the nodes up to the last annotation node are end of scope nodes
342      *         false otherwise
343      */
344     private static boolean isEndOfScope(final DetailAST lastAnnotationNode, final DetailAST node) {
345         DetailAST checkNode = node;
346         boolean endOfScope = true;
347         while (endOfScope && !checkNode.equals(lastAnnotationNode)) {
348             switch (checkNode.getType()) {
349                 case TokenTypes.RCURLY:
350                 case TokenTypes.RBRACK:
351                     while (checkNode.getNextSibling() == null) {
352                         checkNode = checkNode.getParent();
353                     }
354                     checkNode = checkNode.getNextSibling();
355                     break;
356                 default:
357                     endOfScope = false;
358             }
359         }
360         return endOfScope;
361     }
362 
363     /**
364      * Checks that some parent of given node contains given token type.
365      *
366      * @param node node to check
367      * @param type type to look for
368      * @return true if there is a parent of given type
369      */
370     private static boolean isParentContainsTokenType(final DetailAST node, int type) {
371         boolean returnValue = false;
372         for (DetailAST ast = node.getParent(); ast != null; ast = ast.getParent()) {
373             if (ast.getType() == type) {
374                 returnValue = true;
375                 break;
376             }
377         }
378         return returnValue;
379     }
380 
381     /**
382      * Get the column number for the start of a given expression, expanding
383      * tabs out into spaces in the process.
384      *
385      * @param ast   the expression to find the start of
386      *
387      * @return the column number for the start of the expression
388      */
389     private int expandedTabsColumnNo(DetailAST ast) {
390         final String line =
391             indentCheck.getLine(ast.getLineNo() - 1);
392 
393         return CommonUtil.lengthExpandedTabs(line, ast.getColumnNo(),
394             indentCheck.getIndentationTabWidth());
395     }
396 
397     /**
398      * Get the start of the line for the given expression.
399      *
400      * @param ast   the expression to find the start of the line for
401      *
402      * @return the start of the line for the given expression
403      */
404     private int getLineStart(DetailAST ast) {
405         final String line = indentCheck.getLine(ast.getLineNo() - 1);
406         return getLineStart(line);
407     }
408 
409     /**
410      * Get the start of the specified line.
411      *
412      * @param line the specified line number
413      * @return the start of the specified line
414      */
415     private int getLineStart(String line) {
416         int index = 0;
417         while (Character.isWhitespace(line.charAt(index))) {
418             index++;
419         }
420         return CommonUtil.lengthExpandedTabs(line, index, indentCheck.getIndentationTabWidth());
421     }
422 
423     /**
424      * Logs warning message if indentation is incorrect.
425      *
426      * @param currentNode
427      *            current node which probably invoked a violation.
428      * @param currentIndent
429      *            correct indentation.
430      */
431     private void logWarningMessage(DetailAST currentNode, int currentIndent) {
432         if (indentCheck.isForceStrictCondition()) {
433             if (expandedTabsColumnNo(currentNode) != currentIndent) {
434                 indentCheck.indentationLog(currentNode,
435                         IndentationCheck.MSG_ERROR, currentNode.getText(),
436                         expandedTabsColumnNo(currentNode), currentIndent);
437             }
438         }
439         else {
440             if (expandedTabsColumnNo(currentNode) < currentIndent) {
441                 indentCheck.indentationLog(currentNode,
442                         IndentationCheck.MSG_ERROR, currentNode.getText(),
443                         expandedTabsColumnNo(currentNode), currentIndent);
444             }
445         }
446     }
447 
448 }