SeparatorWrapCheck.java
////////////////////////////////////////////////////////////////////////////////
// checkstyle: Checks Java source code for adherence to a set of rules.
// Copyright (C) 2001-2021 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 java.util.Locale;
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 line wrapping with separators.
* </p>
* <ul>
* <li>
* Property {@code option} - Specify policy on how to wrap lines.
* Type is {@code com.puppycrawl.tools.checkstyle.checks.whitespace.WrapOption}.
* Default value is {@code eol}.
* </li>
* <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#DOT">
* DOT</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#COMMA">
* COMMA</a>.
* </li>
* </ul>
* <p>
* To configure the check:
* </p>
* <pre>
* <module name="SeparatorWrap"/>
* </pre>
* <p>
* Example:
* </p>
* <pre>
* import java.io.
* IOException; // OK
*
* class Test {
*
* String s;
*
* public void foo(int a,
* int b) { // OK
* }
*
* public void bar(int p
* , int q) { // violation, separator comma on new line
* if (s
* .isEmpty()) { // violation, separator dot on new line
* }
* }
*
* }
* </pre>
* <p>
* To configure the check for
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#METHOD_REF">
* METHOD_REF</a> at new line:
* </p>
* <pre>
* <module name="SeparatorWrap">
* <property name="tokens" value="METHOD_REF"/>
* <property name="option" value="nl"/>
* </module>
* </pre>
* <p>
* Example:
* </p>
* <pre>
* import java.util.Arrays;
*
* class Test2 {
*
* String[] stringArray = {"foo", "bar"};
*
* void fun() {
* Arrays.sort(stringArray, String::
* compareToIgnoreCase); // violation, separator method reference on same line
* Arrays.sort(stringArray, String
* ::compareTo); // OK
* }
*
* }
* </pre>
* <p>
* To configure the check for comma at the new line:
* </p>
* <pre>
* <module name="SeparatorWrap">
* <property name="tokens" value="COMMA"/>
* <property name="option" value="nl"/>
* </module>
* </pre>
* <p>
* Example:
* </p>
* <pre>
* class Test3 {
*
* String s;
*
* int a,
* b; // violation, separator comma on same line
*
* public void foo(int a,
* int b) { // violation, separator comma on the same line
* int r
* , t; // OK
* }
*
* public void bar(int p
* , int q) { // OK
* }
*
* }
* </pre>
* <p>
* Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
* </p>
* <p>
* Violation Message Keys:
* </p>
* <ul>
* <li>
* {@code line.new}
* </li>
* <li>
* {@code line.previous}
* </li>
* </ul>
*
* @since 5.8
*/
@StatelessCheck
public class SeparatorWrapCheck
extends AbstractCheck {
/**
* A key is pointing to the warning message text in "messages.properties"
* file.
*/
public static final String MSG_LINE_PREVIOUS = "line.previous";
/**
* A key is pointing to the warning message text in "messages.properties"
* file.
*/
public static final String MSG_LINE_NEW = "line.new";
/** Specify policy on how to wrap lines. */
private WrapOption option = WrapOption.EOL;
/**
* Setter to specify policy on how to wrap lines.
*
* @param optionStr string to decode option from
* @throws IllegalArgumentException if unable to decode
*/
public void setOption(String optionStr) {
option = WrapOption.valueOf(optionStr.trim().toUpperCase(Locale.ENGLISH));
}
@Override
public int[] getDefaultTokens() {
return new int[] {
TokenTypes.DOT,
TokenTypes.COMMA,
};
}
@Override
public int[] getAcceptableTokens() {
return new int[] {
TokenTypes.DOT,
TokenTypes.COMMA,
TokenTypes.SEMI,
TokenTypes.ELLIPSIS,
TokenTypes.AT,
TokenTypes.LPAREN,
TokenTypes.RPAREN,
TokenTypes.ARRAY_DECLARATOR,
TokenTypes.RBRACK,
TokenTypes.METHOD_REF,
};
}
@Override
public int[] getRequiredTokens() {
return CommonUtil.EMPTY_INT_ARRAY;
}
@Override
public void visitToken(DetailAST ast) {
final String text = ast.getText();
final int colNo = ast.getColumnNo();
final int lineNo = ast.getLineNo();
final String currentLine = getLines()[lineNo - 1];
final String substringAfterToken =
currentLine.substring(colNo + text.length()).trim();
final String substringBeforeToken =
currentLine.substring(0, colNo).trim();
if (option == WrapOption.EOL
&& substringBeforeToken.isEmpty()) {
log(ast, MSG_LINE_PREVIOUS, text);
}
else if (option == WrapOption.NL
&& substringAfterToken.isEmpty()) {
log(ast, MSG_LINE_NEW, text);
}
}
}