Source code: com/puppycrawl/tools/checkstyle/checks/imports/AvoidStarImportCheck.java
1 ////////////////////////////////////////////////////////////////////////////////
2 // checkstyle: Checks Java source code for adherence to a set of rules.
3 // Copyright (C) 2001-2003 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
20 package com.puppycrawl.tools.checkstyle.checks.imports;
21
22 import com.puppycrawl.tools.checkstyle.api.Check;
23 import com.puppycrawl.tools.checkstyle.api.DetailAST;
24 import com.puppycrawl.tools.checkstyle.api.FullIdent;
25 import com.puppycrawl.tools.checkstyle.api.TokenTypes;
26
27 /**
28 * <p>
29 * Check that finds import statements that use the * notation.
30 * </p>
31 * <p> Rationale: Importing all classes from a package leads to tight coupling
32 * between packages and might lead to problems when a new version of a library
33 * introduces name clashes.
34 * </p>
35 * <p>
36 * An example of how to configure the check is:
37 * </p>
38 * <pre>
39 * <module name="AvoidStarImport">
40 * <property name="excludes" value="java.io,java.net"/>
41 * </module>
42 * </pre>
43 *
44 * The optional "excludes" property allows for certain packages like
45 * java.io or java.net to be exempted from the rule. Note that the excludes
46 * property is not recursive, subpackages of excluded packages are not
47 * automatically excluded.
48 *
49 * @author Oliver Burn
50 * @author <a href="bschneider@vecna.com">Bill Schneider</a>
51 * @version 1.0
52 */
53 public class AvoidStarImportCheck
54 extends Check
55 {
56 /** the packages to exempt from this check */
57 private String[] mExcludes = new String[0];
58
59 /** @see com.puppycrawl.tools.checkstyle.api.Check */
60 public int[] getDefaultTokens()
61 {
62 return new int[] {TokenTypes.IMPORT};
63 }
64
65 /**
66 * Sets the list of packages to exempt from the check.
67 * @param aExcludes a list of package names where star imports are ok
68 */
69 public void setExcludes(String[] aExcludes)
70 {
71 mExcludes = new String[aExcludes.length];
72 for (int i = 0; i < aExcludes.length; i++) {
73 mExcludes[i] = aExcludes[i];
74 if (!mExcludes[i].endsWith(".*")) {
75 // force all package names to end with ".*" to disambiguate
76 // "java.io"
77 mExcludes[i] = mExcludes[i] + ".*";
78 }
79 }
80 }
81
82 /** @see com.puppycrawl.tools.checkstyle.api.Check */
83 public void visitToken(DetailAST aAST)
84 {
85 final FullIdent name = FullIdent.createFullIdentBelow(aAST);
86 if ((name != null) && name.getText().endsWith(".*")) {
87 boolean exempt = false;
88 for (int i = 0; i < mExcludes.length && !exempt; i++) {
89 if (name.getText().equals(mExcludes[i])) {
90 exempt = true;
91 }
92 }
93 if (!exempt) {
94 log(aAST.getLineNo(), "import.avoidStar", name.getText());
95 }
96 }
97 }
98 }