WhitespaceAfterCheck.java
///////////////////////////////////////////////////////////////////////////////////////////////
// checkstyle: Checks Java source code and other text files for adherence to a set of rules.
// Copyright (C) 2001-2022 the original author or authors.
//
// 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.whitespace;
import com.puppycrawl.tools.checkstyle.StatelessCheck;
import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
import com.puppycrawl.tools.checkstyle.api.DetailAST;
import com.puppycrawl.tools.checkstyle.api.TokenTypes;
import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
/**
* <p>
* Checks that a token is followed by whitespace, with the exception that it
* does not check for whitespace after the semicolon of an empty for iterator.
* Use Check <a href="https://checkstyle.org/config_whitespace.html#EmptyForIteratorPad">
* EmptyForIteratorPad</a> to validate empty for iterators.
* </p>
* <ul>
* <li>
* Property {@code tokens} - tokens to check
* Type is {@code java.lang.String[]}.
* Validation type is {@code tokenSet}.
* Default value is:
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#COMMA">
* COMMA</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#SEMI">
* SEMI</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#TYPECAST">
* TYPECAST</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LITERAL_IF">
* LITERAL_IF</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LITERAL_ELSE">
* LITERAL_ELSE</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LITERAL_WHILE">
* LITERAL_WHILE</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LITERAL_DO">
* LITERAL_DO</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LITERAL_FOR">
* LITERAL_FOR</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LITERAL_FINALLY">
* LITERAL_FINALLY</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LITERAL_RETURN">
* LITERAL_RETURN</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LITERAL_YIELD">
* LITERAL_YIELD</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LITERAL_CATCH">
* LITERAL_CATCH</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LITERAL_DO">
* DO_WHILE</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#ELLIPSIS">
* ELLIPSIS</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LITERAL_SWITCH">
* LITERAL_SWITCH</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LITERAL_SYNCHRONIZED">
* LITERAL_SYNCHRONIZED</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LITERAL_TRY">
* LITERAL_TRY</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LITERAL_CASE">
* LITERAL_CASE</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LAMBDA">
* LAMBDA</a>.
* </li>
* </ul>
* <p>
* To configure the check:
* </p>
* <pre>
* <module name="WhitespaceAfter"/>
* </pre>
* <p>Example:</p>
* <pre>
* public void myTest() {
* if (foo) { // OK
* //...
* } else if(bar) { // violation
* //...
* }
*
* testMethod(foo, bar); // OK
* testMethod(foo,bar); // violation
*
* for (;;){} // OK
* for(;;){} // violation, space after 'for' is required
*
* try (InputStream ignored = System.in) {} // OK
* try(InputStream ignored = System.in) {} // violation ''try' is not followed by whitespace'
*
* try {} catch (Exception e){} // OK
* try{} catch (Exception e){} // violation ''try' is not followed by whitespace'
*
* try {} finally {} // OK
* try {} finally{} // violation ''finally' is not followed by whitespace'
*
* try {} catch (Error e){} finally {} // OK
* try {} catch (Error e){} finally{} // violation ''finally' is not followed by whitespace'
*
* try {} catch (Exception e){} // OK
* try {} catch(Exception e){} // violation ''catch' is not followed by whitespace'
*
* synchronized (this) { } // OK
* synchronized(this) { } // violation ''synchronized' is not followed by whitespace'
* }
* public String testOne() {
* return ("a" + "b"); // OK
* }
* public String testTwo() {
* return("a" + "b"); // violation 'return' is not followed by whitespace'
* }
* public static void main(String[] args) {
* int a = switch (args[0]) {
* case "got":
* yield (1); // OK
* case "my":
* yield(3); // violation ''yield' is not followed by whitespace'
* default:
* yield 2;
* };
* }
* </pre>
* <p>
* To configure the check for whitespace only after COMMA and SEMI tokens:
* </p>
* <pre>
* <module name="WhitespaceAfter">
* <property name="tokens" value="COMMA, SEMI"/>
* </module>
* </pre>
* <p>Example:</p>
* <pre>
* public void myTest() {
* int a; int b; // OK
* int a;int b; // violation
*
* testMethod(foo, bar); // OK
* testMethod(foo,bar); // violation
*
* for(;;) {} // OK
* }
* </pre>
* <p>
* Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
* </p>
* <p>
* Violation Message Keys:
* </p>
* <ul>
* <li>
* {@code ws.notFollowed}
* </li>
* <li>
* {@code ws.typeCast}
* </li>
* </ul>
*
* @since 3.0
*/
@StatelessCheck
public class WhitespaceAfterCheck
extends AbstractCheck {
/**
* A key is pointing to the warning message text in "messages.properties"
* file.
*/
public static final String MSG_WS_NOT_FOLLOWED = "ws.notFollowed";
/**
* A key is pointing to the warning message text in "messages.properties"
* file.
*/
public static final String MSG_WS_TYPECAST = "ws.typeCast";
@Override
public int[] getDefaultTokens() {
return getAcceptableTokens();
}
@Override
public int[] getAcceptableTokens() {
return new int[] {
TokenTypes.COMMA,
TokenTypes.SEMI,
TokenTypes.TYPECAST,
TokenTypes.LITERAL_IF,
TokenTypes.LITERAL_ELSE,
TokenTypes.LITERAL_WHILE,
TokenTypes.LITERAL_DO,
TokenTypes.LITERAL_FOR,
TokenTypes.LITERAL_FINALLY,
TokenTypes.LITERAL_RETURN,
TokenTypes.LITERAL_YIELD,
TokenTypes.LITERAL_CATCH,
TokenTypes.DO_WHILE,
TokenTypes.ELLIPSIS,
TokenTypes.LITERAL_SWITCH,
TokenTypes.LITERAL_SYNCHRONIZED,
TokenTypes.LITERAL_TRY,
TokenTypes.LITERAL_CASE,
TokenTypes.LAMBDA,
};
}
@Override
public int[] getRequiredTokens() {
return CommonUtil.EMPTY_INT_ARRAY;
}
@Override
public void visitToken(DetailAST ast) {
if (ast.getType() == TokenTypes.TYPECAST) {
final DetailAST targetAST = ast.findFirstToken(TokenTypes.RPAREN);
final int[] line = getLineCodePoints(targetAST.getLineNo() - 1);
if (!isFollowedByWhitespace(targetAST, line)) {
log(targetAST, MSG_WS_TYPECAST);
}
}
else {
final int[] line = getLineCodePoints(ast.getLineNo() - 1);
if (!isFollowedByWhitespace(ast, line)) {
final Object[] message = {ast.getText()};
log(ast, MSG_WS_NOT_FOLLOWED, message);
}
}
}
/**
* Checks whether token is followed by a whitespace.
*
* @param targetAST Ast token.
* @param line Unicode code points array of line associated with the ast token.
* @return true if ast token is followed by a whitespace.
*/
private static boolean isFollowedByWhitespace(DetailAST targetAST, int... line) {
final int after =
targetAST.getColumnNo() + targetAST.getText().length();
boolean followedByWhitespace = true;
if (after < line.length) {
final int codePoint = line[after];
followedByWhitespace = codePoint == ';'
|| codePoint == ')'
|| Character.isWhitespace(codePoint);
}
return followedByWhitespace;
}
}