HeaderCheck.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.header;
import java.io.File;
import java.util.BitSet;
import com.puppycrawl.tools.checkstyle.StatelessCheck;
import com.puppycrawl.tools.checkstyle.api.FileText;
import com.puppycrawl.tools.checkstyle.utils.TokenUtil;
/**
* <p>
* Checks that a source file begins with a specified header.
* Property {@code headerFile} specifies a file that contains the required header.
* Alternatively, the header specification can be set directly in the
* {@code header} property without the need for an external file.
* </p>
* <p>
* Property {@code ignoreLines} specifies the line numbers to ignore when matching
* lines in a header file. This property is very useful for supporting headers
* that contain copyright dates. For example, consider the following header:
* </p>
* <pre>
* line 1: ////////////////////////////////////////////////////////////////////
* line 2: // checkstyle:
* line 3: // Checks Java source code for adherence to a set of rules.
* line 4: // Copyright (C) 2002 Oliver Burn
* line 5: ////////////////////////////////////////////////////////////////////
* </pre>
* <p>
* Since the year information will change over time, you can tell Checkstyle
* to ignore line 4 by setting property {@code ignoreLines} to {@code 4}.
* </p>
* <p>
* In default configuration, if header is not specified, the default value
* of header is set to {@code null} and the check does not rise any violations.
* </p>
* <ul>
* <li>
* Property {@code headerFile} - Specify the name of the file containing the required header.
* Type is {@code java.net.URI}.
* Default value is {@code null}.
* </li>
* <li>
* Property {@code charset} - Specify the character encoding to use when reading the headerFile.
* Type is {@code java.lang.String}.
* Default value is {@code the charset property of the parent
* <a href="https://checkstyle.org/config.html#Checker">Checker</a> module}.
* </li>
* <li>
* Property {@code header} - Specify the required header specified inline.
* Individual header lines must be separated by the string {@code "\n"}
* (even on platforms with a different line separator), see examples below.
* Type is {@code java.lang.String}.
* Default value is {@code null}.
* </li>
* <li>
* Property {@code ignoreLines} - Specify the line numbers to ignore.
* Type is {@code int[]}.
* Default value is {@code ""}.
* </li>
* <li>
* Property {@code fileExtensions} - Specify the file type extension of files to process.
* Type is {@code java.lang.String[]}.
* Default value is {@code ""}.
* </li>
* </ul>
* <p>
* To configure the check such that no violations arise.
* Default values of properties are used.
* </p>
* <pre>
* <module name="Header"/>
* </pre>
* <p>
* To configure the check to use header file {@code "config/java.header"}
* and ignore lines {@code 2}, {@code 3}, and {@code 4} and only process Java files:
* </p>
* <pre>
* <module name="Header">
* <property name="headerFile" value="config/java.header"/>
* <property name="ignoreLines" value="2, 3, 4"/>
* <property name="fileExtensions" value="java"/>
* </module>
* </pre>
* <p>
* To configure the check to verify that each file starts with the header
* </p>
* <pre>
* // Copyright (C) 2004 MyCompany
* // All rights reserved
* </pre>
* <p>
* without the need for an external header file:
* </p>
* <pre>
* <module name="Header">
* <property name="header"
* value="// Copyright (C) 2004 MyCompany\n// All rights reserved"/>
* </module>
* </pre>
* <p>
* Parent is {@code com.puppycrawl.tools.checkstyle.Checker}
* </p>
* <p>
* Violation Message Keys:
* </p>
* <ul>
* <li>
* {@code header.mismatch}
* </li>
* <li>
* {@code header.missing}
* </li>
* </ul>
*
* @since 6.9
*/
@StatelessCheck
public class HeaderCheck extends AbstractHeaderCheck {
/**
* A key is pointing to the warning message text in "messages.properties"
* file.
*/
public static final String MSG_MISSING = "header.missing";
/**
* A key is pointing to the warning message text in "messages.properties"
* file.
*/
public static final String MSG_MISMATCH = "header.mismatch";
/** Specify the line numbers to ignore. */
private BitSet ignoreLines = new BitSet();
/**
* Returns true if lineNo is header lines or false.
*
* @param lineNo a line number
* @return if {@code lineNo} is one of the ignored header lines.
*/
private boolean isIgnoreLine(int lineNo) {
return ignoreLines.get(lineNo);
}
/**
* Checks if a code line matches the required header line.
*
* @param lineNumber the line number to check against the header
* @param line the line contents
* @return true if and only if the line matches the required header line
*/
private boolean isMatch(int lineNumber, String line) {
// skip lines we are meant to ignore
return isIgnoreLine(lineNumber + 1)
|| getHeaderLines().get(lineNumber).equals(line);
}
/**
* Setter to specify the line numbers to ignore.
*
* @param lines line numbers to ignore in header.
*/
public void setIgnoreLines(int... lines) {
ignoreLines = TokenUtil.asBitSet(lines);
}
@Override
protected void processFiltered(File file, FileText fileText) {
if (getHeaderLines().size() > fileText.size()) {
log(1, MSG_MISSING);
}
else {
for (int i = 0; i < getHeaderLines().size(); i++) {
if (!isMatch(i, fileText.get(i))) {
log(i + 1, MSG_MISMATCH, getHeaderLines().get(i));
break;
}
}
}
}
@Override
protected void postProcessHeaderLines() {
// no code
}
}