////////////////////////////////////////////////////////////////////////////////
// checkstyle: Checks Java source code for adherence to a set of rules.
// Copyright (C) 2001-2017 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.sizes;
import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
import com.puppycrawl.tools.checkstyle.api.DetailAST;
import com.puppycrawl.tools.checkstyle.api.FileContents;
import com.puppycrawl.tools.checkstyle.api.TokenTypes;
import com.puppycrawl.tools.checkstyle.utils.CommonUtils;
/**
* <p>
* Checks for long methods.
* </p>
* <p>
* Rationale: If a method becomes very long it is hard to understand.
* Therefore long methods should usually be refactored into several
* individual methods that focus on a specific task.
* </p>
*<p>
* The default maximum method length is 150 lines. To change the maximum
* number of lines, set property max.
* </p>
* <p>
* An example of how to configure the check is:
* </p>
* <pre>
* <module name="MethodLength"/>
* </pre>
* <p>
* An example of how to configure the check so that it accepts methods with at
* most 60 lines is:
* </p>
* <pre>
* <module name="MethodLength">
* <property name="max" value="60"/>
* </module>
* </pre>
* @author Lars Kühne
*/
public class MethodLengthCheck extends AbstractCheck {
/**
* A key is pointing to the warning message text in "messages.properties"
* file.
*/
public static final String MSG_KEY = "maxLen.method";
/** Default maximum number of lines. */
private static final int DEFAULT_MAX_LINES = 150;
/** Whether to ignore empty lines and single line comments. */
private boolean countEmpty = true;
/** The maximum number of lines. */
private int max = DEFAULT_MAX_LINES;
@Override
public int[] getDefaultTokens() {
return getAcceptableTokens();
}
@Override
public int[] getAcceptableTokens() {
return new int[] {TokenTypes.METHOD_DEF, TokenTypes.CTOR_DEF};
}
@Override
public int[] getRequiredTokens() {
return CommonUtils.EMPTY_INT_ARRAY;
}
@Override
public void visitToken(DetailAST ast) {
final DetailAST openingBrace = ast.findFirstToken(TokenTypes.SLIST);
if (openingBrace != null) {
final DetailAST closingBrace =
openingBrace.findFirstToken(TokenTypes.RCURLY);
final int length = getLengthOfBlock(openingBrace, closingBrace);
if (length > max) {
log(ast.getLineNo(), ast.getColumnNo(), MSG_KEY,
length, max);
}
}
}
/**
* Returns length of code only without comments and blank lines.
* @param openingBrace block opening brace
* @param closingBrace block closing brace
* @return number of lines with code for current block
*/
private int getLengthOfBlock(DetailAST openingBrace, DetailAST closingBrace) {
int length = closingBrace.getLineNo() - openingBrace.getLineNo() + 1;
if (!countEmpty) {
final FileContents contents = getFileContents();
final int lastLine = closingBrace.getLineNo();
for (int i = openingBrace.getLineNo() - 1; i < lastLine; i++) {
if (contents.lineIsBlank(i) || contents.lineIsComment(i)) {
length--;
}
}
}
return length;
}
/**
* @param length the maximum length of a method.
*/
public void setMax(int length) {
max = length;
}
/**
* @param countEmpty whether to count empty and single line comments
* of the form //.
*/
public void setCountEmpty(boolean countEmpty) {
this.countEmpty = countEmpty;
}
}