Coverage Report

Coverage Report - com.puppycrawl.tools.checkstyle.checks.coding.ParameterAssignmentCheck

Classes in this File

Line Coverage

Branch Coverage

Complexity

ParameterAssignmentCheck

93%

41/44

32%

17/52

5.091

 ////////////////////////////////////////////////////////////////////////////////
 // checkstyle: Checks Java source code for adherence to a set of rules.
 // Copyright (C) 2001-2014  Oliver Burn
 //
 // This library is free software; you can redistribute it and/or
 // modify it under the terms of the GNU Lesser General Public
 // License as published by the Free Software Foundation; either
 // version 2.1 of the License, or (at your option) any later version.
 //
 // This library is distributed in the hope that it will be useful,
 // but WITHOUT ANY WARRANTY; without even the implied warranty of
 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 // Lesser General Public License for more details.
 //
 // You should have received a copy of the GNU Lesser General Public
 // License along with this library; if not, write to the Free Software
 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 ////////////////////////////////////////////////////////////////////////////////
 package com.puppycrawl.tools.checkstyle.checks.coding;
 
 import com.google.common.collect.Sets;
 import com.puppycrawl.tools.checkstyle.api.Check;
 import com.puppycrawl.tools.checkstyle.api.DetailAST;
 import com.puppycrawl.tools.checkstyle.api.FastStack;
 import com.puppycrawl.tools.checkstyle.api.TokenTypes;
 import java.util.Set;
 
 /**
  * <p>
  * Disallow assignment of parameters.
  * </p>
  * <p>
  * Rationale:
  * Parameter assignment is often considered poor
  * programming practice. Forcing developers to declare
  * parameters as final is often onerous. Having a check
  * ensure that parameters are never assigned would give
  * the best of both worlds.
  * </p>
  * @author <a href="mailto:simon@redhillconsulting.com.au">Simon Harris</a>
  */
 public final class ParameterAssignmentCheck extends Check
 {
     /** Stack of methods' parameters. */
     private final FastStack<Set<String>> mParameterNamesStack =
         FastStack.newInstance();
     /** Current set of perameters. */
     private Set<String> mParameterNames;
 
     @Override
     public int[] getDefaultTokens()
     {
         return new int[] {
             TokenTypes.CTOR_DEF,
             TokenTypes.METHOD_DEF,
             TokenTypes.ASSIGN,
             TokenTypes.PLUS_ASSIGN,
             TokenTypes.MINUS_ASSIGN,
             TokenTypes.STAR_ASSIGN,
             TokenTypes.DIV_ASSIGN,
             TokenTypes.MOD_ASSIGN,
             TokenTypes.SR_ASSIGN,
             TokenTypes.BSR_ASSIGN,
             TokenTypes.SL_ASSIGN,
             TokenTypes.BAND_ASSIGN,
             TokenTypes.BXOR_ASSIGN,
             TokenTypes.BOR_ASSIGN,
             TokenTypes.INC,
             TokenTypes.POST_INC,
             TokenTypes.DEC,
             TokenTypes.POST_DEC,
         };
     }
 
     @Override
     public int[] getRequiredTokens()
     {
         return getDefaultTokens();
     }
 
     @Override
     public void beginTree(DetailAST aRootAST)
     {
         // clear data
         mParameterNamesStack.clear();
         mParameterNames = null;
     }
 
     @Override
     public void visitToken(DetailAST aAST)
     {
         switch (aAST.getType()) {
         case TokenTypes.CTOR_DEF:
         case TokenTypes.METHOD_DEF:
             visitMethodDef(aAST);
             break;
         case TokenTypes.ASSIGN:
         case TokenTypes.PLUS_ASSIGN:
         case TokenTypes.MINUS_ASSIGN:
         case TokenTypes.STAR_ASSIGN:
         case TokenTypes.DIV_ASSIGN:
         case TokenTypes.MOD_ASSIGN:
         case TokenTypes.SR_ASSIGN:
         case TokenTypes.BSR_ASSIGN:
         case TokenTypes.SL_ASSIGN:
         case TokenTypes.BAND_ASSIGN:
         case TokenTypes.BXOR_ASSIGN:
         case TokenTypes.BOR_ASSIGN:
             visitAssign(aAST);
             break;
         case TokenTypes.INC:
         case TokenTypes.POST_INC:
         case TokenTypes.DEC:
         case TokenTypes.POST_DEC:
             visitIncDec(aAST);
             break;
         default:
             throw new IllegalStateException(aAST.toString());
         }
     }
 
     @Override
     public void leaveToken(DetailAST aAST)
     {
         switch (aAST.getType()) {
         case TokenTypes.CTOR_DEF:
         case TokenTypes.METHOD_DEF:
             leaveMethodDef();
             break;
         case TokenTypes.ASSIGN:
         case TokenTypes.PLUS_ASSIGN:
         case TokenTypes.MINUS_ASSIGN:
         case TokenTypes.STAR_ASSIGN:
         case TokenTypes.DIV_ASSIGN:
         case TokenTypes.MOD_ASSIGN:
         case TokenTypes.SR_ASSIGN:
         case TokenTypes.BSR_ASSIGN:
         case TokenTypes.SL_ASSIGN:
         case TokenTypes.BAND_ASSIGN:
         case TokenTypes.BXOR_ASSIGN:
         case TokenTypes.BOR_ASSIGN:
         case TokenTypes.INC:
         case TokenTypes.POST_INC:
         case TokenTypes.DEC:
         case TokenTypes.POST_DEC:
             // Do nothing
             break;
         default:
             throw new IllegalStateException(aAST.toString());
         }
     }
 
     /**
      * Ckecks if this is assignments of parameter.
      * @param aAST assignment to check.
      */
     private void visitAssign(DetailAST aAST)
     {
         checkIdent(aAST);
     }
 
     /**
      * Checks if this is increment/decrement of parameter.
      * @param aAST dec/inc to check.
      */
     private void visitIncDec(DetailAST aAST)
     {
         checkIdent(aAST);
     }
 
     /**
      * Check if ident is parameter.
      * @param aAST ident to check.
      */
     private void checkIdent(DetailAST aAST)
     {
         if ((mParameterNames != null) && !mParameterNames.isEmpty()) {
             final DetailAST identAST = aAST.getFirstChild();
 
             if ((identAST != null)
                 && (identAST.getType() == TokenTypes.IDENT)
                 && mParameterNames.contains(identAST.getText()))
             {
                 log(aAST.getLineNo(), aAST.getColumnNo(),
                     "parameter.assignment", identAST.getText());
             }
         }
     }
 
     /**
      * Creates new set of parameters and store old one in stack.
      * @param aAST a method to process.
      */
     private void visitMethodDef(DetailAST aAST)
     {
         mParameterNamesStack.push(mParameterNames);
         mParameterNames = Sets.newHashSet();
 
         visitMethodParameters(aAST.findFirstToken(TokenTypes.PARAMETERS));
     }
 
     /** Restores old set of parameters. */
     private void leaveMethodDef()
     {
         mParameterNames = mParameterNamesStack.pop();
     }
 
     /**
      * Creates new parameter set for given method.
      * @param aAST a method for process.
      */
     private void visitMethodParameters(DetailAST aAST)
     {
         DetailAST parameterDefAST =
             aAST.findFirstToken(TokenTypes.PARAMETER_DEF);
 
         for (; parameterDefAST != null;
              parameterDefAST = parameterDefAST.getNextSibling())
         {
             if (parameterDefAST.getType() == TokenTypes.PARAMETER_DEF) {
                 final DetailAST param =
                     parameterDefAST.findFirstToken(TokenTypes.IDENT);
                 mParameterNames.add(param.getText());
             }
         }
     }
 }

1		////////////////////////////////////////////////////////////////////////////////
2		// checkstyle: Checks Java source code for adherence to a set of rules.
3		// Copyright (C) 2001-2014 Oliver Burn
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		package com.puppycrawl.tools.checkstyle.checks.coding;
20
21		import com.google.common.collect.Sets;
22		import com.puppycrawl.tools.checkstyle.api.Check;
23		import com.puppycrawl.tools.checkstyle.api.DetailAST;
24		import com.puppycrawl.tools.checkstyle.api.FastStack;
25		import com.puppycrawl.tools.checkstyle.api.TokenTypes;
26		import java.util.Set;
27
28		/**
29		* <p>
30		* Disallow assignment of parameters.
31		* </p>
32		* <p>
33		* Rationale:
34		* Parameter assignment is often considered poor
35		* programming practice. Forcing developers to declare
36		* parameters as final is often onerous. Having a check
37		* ensure that parameters are never assigned would give
38		* the best of both worlds.
39		* </p>
40		* @author <a href="mailto:simon@redhillconsulting.com.au">Simon Harris</a>
41		*/
42	1	public final class ParameterAssignmentCheck extends Check
43		{
44		/** Stack of methods' parameters. */
45	1	private final FastStack<Set<String>> mParameterNamesStack =
46		FastStack.newInstance();
47		/** Current set of perameters. */
48		private Set<String> mParameterNames;
49
50		@Override
51		public int[] getDefaultTokens()
52		{
53	1	return new int[] {
54		TokenTypes.CTOR_DEF,
55		TokenTypes.METHOD_DEF,
56		TokenTypes.ASSIGN,
57		TokenTypes.PLUS_ASSIGN,
58		TokenTypes.MINUS_ASSIGN,
59		TokenTypes.STAR_ASSIGN,
60		TokenTypes.DIV_ASSIGN,
61		TokenTypes.MOD_ASSIGN,
62		TokenTypes.SR_ASSIGN,
63		TokenTypes.BSR_ASSIGN,
64		TokenTypes.SL_ASSIGN,
65		TokenTypes.BAND_ASSIGN,
66		TokenTypes.BXOR_ASSIGN,
67		TokenTypes.BOR_ASSIGN,
68		TokenTypes.INC,
69		TokenTypes.POST_INC,
70		TokenTypes.DEC,
71		TokenTypes.POST_DEC,
72		};
73		}
74
75		@Override
76		public int[] getRequiredTokens()
77		{
78	0	return getDefaultTokens();
79		}
80
81		@Override
82		public void beginTree(DetailAST aRootAST)
83		{
84		// clear data
85	1	mParameterNamesStack.clear();
86	1	mParameterNames = null;
87	1	}
88
89		@Override
90		public void visitToken(DetailAST aAST)
91		{
92	13	switch (aAST.getType()) {
93		case TokenTypes.CTOR_DEF:
94		case TokenTypes.METHOD_DEF:
95	3	visitMethodDef(aAST);
96	3	break;
97		case TokenTypes.ASSIGN:
98		case TokenTypes.PLUS_ASSIGN:
99		case TokenTypes.MINUS_ASSIGN:
100		case TokenTypes.STAR_ASSIGN:
101		case TokenTypes.DIV_ASSIGN:
102		case TokenTypes.MOD_ASSIGN:
103		case TokenTypes.SR_ASSIGN:
104		case TokenTypes.BSR_ASSIGN:
105		case TokenTypes.SL_ASSIGN:
106		case TokenTypes.BAND_ASSIGN:
107		case TokenTypes.BXOR_ASSIGN:
108		case TokenTypes.BOR_ASSIGN:
109	7	visitAssign(aAST);
110	7	break;
111		case TokenTypes.INC:
112		case TokenTypes.POST_INC:
113		case TokenTypes.DEC:
114		case TokenTypes.POST_DEC:
115	3	visitIncDec(aAST);
116	3	break;
117		default:
118	0	throw new IllegalStateException(aAST.toString());
119		}
120	13	}
121
122		@Override
123		public void leaveToken(DetailAST aAST)
124		{
125	13	switch (aAST.getType()) {
126		case TokenTypes.CTOR_DEF:
127		case TokenTypes.METHOD_DEF:
128	3	leaveMethodDef();
129	3	break;
130		case TokenTypes.ASSIGN:
131		case TokenTypes.PLUS_ASSIGN:
132		case TokenTypes.MINUS_ASSIGN:
133		case TokenTypes.STAR_ASSIGN:
134		case TokenTypes.DIV_ASSIGN:
135		case TokenTypes.MOD_ASSIGN:
136		case TokenTypes.SR_ASSIGN:
137		case TokenTypes.BSR_ASSIGN:
138		case TokenTypes.SL_ASSIGN:
139		case TokenTypes.BAND_ASSIGN:
140		case TokenTypes.BXOR_ASSIGN:
141		case TokenTypes.BOR_ASSIGN:
142		case TokenTypes.INC:
143		case TokenTypes.POST_INC:
144		case TokenTypes.DEC:
145		case TokenTypes.POST_DEC:
146		// Do nothing
147	10	break;
148		default:
149	0	throw new IllegalStateException(aAST.toString());
150		}
151	13	}
152
153		/**
154		* Ckecks if this is assignments of parameter.
155		* @param aAST assignment to check.
156		*/
157		private void visitAssign(DetailAST aAST)
158		{
159	7	checkIdent(aAST);
160	7	}
161
162		/**
163		* Checks if this is increment/decrement of parameter.
164		* @param aAST dec/inc to check.
165		*/
166		private void visitIncDec(DetailAST aAST)
167		{
168	3	checkIdent(aAST);
169	3	}
170
171		/**
172		* Check if ident is parameter.
173		* @param aAST ident to check.
174		*/
175		private void checkIdent(DetailAST aAST)
176		{
177	10	if ((mParameterNames != null) && !mParameterNames.isEmpty()) {
178	9	final DetailAST identAST = aAST.getFirstChild();
179
180	9	if ((identAST != null)
181		&& (identAST.getType() == TokenTypes.IDENT)
182		&& mParameterNames.contains(identAST.getText()))
183		{
184	4	log(aAST.getLineNo(), aAST.getColumnNo(),
185		"parameter.assignment", identAST.getText());
186		}
187		}
188	10	}
189
190		/**
191		* Creates new set of parameters and store old one in stack.
192		* @param aAST a method to process.
193		*/
194		private void visitMethodDef(DetailAST aAST)
195		{
196	3	mParameterNamesStack.push(mParameterNames);
197	3	mParameterNames = Sets.newHashSet();
198
199	3	visitMethodParameters(aAST.findFirstToken(TokenTypes.PARAMETERS));
200	3	}
201
202		/** Restores old set of parameters. */
203		private void leaveMethodDef()
204		{
205	3	mParameterNames = mParameterNamesStack.pop();
206	3	}
207
208		/**
209		* Creates new parameter set for given method.
210		* @param aAST a method for process.
211		*/
212		private void visitMethodParameters(DetailAST aAST)
213		{
214	3	DetailAST parameterDefAST =
215		aAST.findFirstToken(TokenTypes.PARAMETER_DEF);
216
217	7	for (; parameterDefAST != null;
218	4	parameterDefAST = parameterDefAST.getNextSibling())
219		{
220	4	if (parameterDefAST.getType() == TokenTypes.PARAMETER_DEF) {
221	3	final DetailAST param =
222		parameterDefAST.findFirstToken(TokenTypes.IDENT);
223	3	mParameterNames.add(param.getText());
224		}
225		}
226	3	}
227		}