1 ////////////////////////////////////////////////////////////////////////////////
2 // checkstyle: Checks Java source code for adherence to a set of rules.
3 // Copyright (C) 2001-2019 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 com.puppycrawl.tools.checkstyle.api.DetailAST;
23
24 /**
25 * Handler for lambda expressions.
26 *
27 */
28 public class LambdaHandler extends AbstractExpressionHandler {
29
30 /**
31 * Construct an instance of this handler with the given indentation check,
32 * abstract syntax tree, and parent handler.
33 *
34 * @param indentCheck the indentation check
35 * @param ast the abstract syntax tree
36 * @param parent the parent handler
37 */
38 public LambdaHandler(IndentationCheck indentCheck,
39 DetailAST ast, AbstractExpressionHandler parent) {
40 super(indentCheck, "lambda", ast, parent);
41 }
42
43 @Override
44 public IndentLevel getSuggestedChildIndent(AbstractExpressionHandler child) {
45 return getIndent();
46 }
47
48 /**
49 * {@inheritDoc}.
50 * @noinspection MethodWithMultipleReturnPoints
51 */
52 @Override
53 protected IndentLevel getIndentImpl() {
54 if (getParent() instanceof MethodCallHandler) {
55 return getParent().getSuggestedChildIndent(this);
56 }
57
58 DetailAST parent = getMainAst().getParent();
59 if (getParent() instanceof NewHandler) {
60 parent = parent.getParent();
61 }
62
63 // Use the start of the parent's line as the reference indentation level.
64 IndentLevel level = new IndentLevel(getLineStart(parent));
65
66 // If the start of the lambda is the first element on the line;
67 // assume line wrapping with respect to its parent.
68 final DetailAST firstChild = getMainAst().getFirstChild();
69 if (getLineStart(firstChild) == firstChild.getColumnNo()) {
70 level = new IndentLevel(level, getIndentCheck().getLineWrappingIndentation());
71 }
72
73 return level;
74 }
75
76 @Override
77 public void checkIndentation() {
78 // If the argument list is the first element on the line
79 final DetailAST firstChild = getMainAst().getFirstChild();
80 if (getLineStart(firstChild) == firstChild.getColumnNo()) {
81 final IndentLevel level = getIndent();
82 if (!level.isAcceptable(firstChild.getColumnNo())) {
83 logError(firstChild, "arguments", firstChild.getColumnNo(), level);
84 }
85 }
86
87 // If the "->" is the first element on the line, assume line wrapping.
88 if (getLineStart(getMainAst()) == getMainAst().getColumnNo()) {
89 final IndentLevel level =
90 new IndentLevel(getIndent(), getIndentCheck().getLineWrappingIndentation());
91 if (!level.isAcceptable(getMainAst().getColumnNo())) {
92 logError(getMainAst(), "", getMainAst().getColumnNo(), level);
93 }
94 }
95 }
96
97 }