Java tutorial
//////////////////////////////////////////////////////////////////////////////// // checkstyle: Checks Java source code for adherence to a set of rules. // Copyright (C) 2001-2016 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.api; import java.util.Collections; import java.util.Set; import org.apache.commons.lang3.ArrayUtils; import com.google.common.collect.Sets; import com.puppycrawl.tools.checkstyle.utils.CommonUtils; /** * The base class for checks. * * @author Oliver Burn * @see <a href="{@docRoot}/../writingchecks.html" target="_top">Writing * your own checks</a> */ public abstract class AbstractCheck extends AbstractViolationReporter { /** Default tab width for column reporting. */ private static final int DEFAULT_TAB_WIDTH = 8; /** The tokens the check is interested in. */ private final Set<String> tokens = Sets.newHashSet(); /** The current file contents. */ private FileContents fileContents; /** The object for collecting messages. */ private LocalizedMessages messages; /** The tab width for column reporting. */ private int tabWidth = DEFAULT_TAB_WIDTH; /** * The class loader to load external classes. Not initialized as this must * be set by my creator. */ private ClassLoader classLoader; /** * Returns the default token a check is interested in. Only used if the * configuration for a check does not define the tokens. * @return the default tokens * @see TokenTypes */ public abstract int[] getDefaultTokens(); /** * Whether comment nodes are required or not. * @return false as a default value. */ public boolean isCommentNodesRequired() { return false; } /** * The configurable token set. * Used to protect Checks against malicious users who specify an * unacceptable token set in the configuration file. * The default implementation returns the check's default tokens. * @return the token set this check is designed for. * @see TokenTypes */ public int[] getAcceptableTokens() { final int[] defaultTokens = getDefaultTokens(); final int[] copy = new int[defaultTokens.length]; System.arraycopy(defaultTokens, 0, copy, 0, defaultTokens.length); return copy; } /** * The tokens that this check must be registered for. * @return the token set this must be registered for. * @see TokenTypes */ public int[] getRequiredTokens() { return ArrayUtils.EMPTY_INT_ARRAY; } /** * Adds a set of tokens the check is interested in. * @param strRep the string representation of the tokens interested in */ public final void setTokens(String... strRep) { Collections.addAll(tokens, strRep); } /** * Returns the tokens registered for the check. * @return the set of token names */ public final Set<String> getTokenNames() { return Collections.unmodifiableSet(tokens); } /** * Set the global object used to collect messages. * @param messages the messages to log with */ public final void setMessages(LocalizedMessages messages) { this.messages = messages; } /** * Initialize the check. This is the time to verify that the check has * everything required to perform it job. */ public void init() { // No code by default, should be overridden only by demand at subclasses } /** * Destroy the check. It is being retired from service. */ public void destroy() { // No code by default, should be overridden only by demand at subclasses } /** * Called before the starting to process a tree. Ideal place to initialize * information that is to be collected whilst processing a tree. * @param rootAST the root of the tree */ public void beginTree(DetailAST rootAST) { // No code by default, should be overridden only by demand at subclasses } /** * Called after finished processing a tree. Ideal place to report on * information collected whilst processing a tree. * @param rootAST the root of the tree */ public void finishTree(DetailAST rootAST) { // No code by default, should be overridden only by demand at subclasses } /** * Called to process a token. * @param ast the token to process */ public void visitToken(DetailAST ast) { // No code by default, should be overridden only by demand at subclasses } /** * Called after all the child nodes have been process. * @param ast the token leaving */ public void leaveToken(DetailAST ast) { // No code by default, should be overridden only by demand at subclasses } /** * Returns the lines associated with the tree. * @return the file contents */ public final String[] getLines() { return fileContents.getLines(); } /** * Returns the line associated with the tree. * @param index index of the line * @return the line from the file contents */ public final String getLine(int index) { return fileContents.getLine(index); } /** * Set the file contents associated with the tree. * @param contents the manager */ public final void setFileContents(FileContents contents) { fileContents = contents; } /** * Returns the file contents associated with the tree. * @return the file contents */ public final FileContents getFileContents() { return fileContents; } /** * Set the class loader associated with the tree. * @param classLoader the class loader */ public final void setClassLoader(ClassLoader classLoader) { this.classLoader = classLoader; } /** * Returns the class loader associated with the tree. * @return the class loader */ public final ClassLoader getClassLoader() { return classLoader; } /** * Get tab width to report errors with. * @return the tab width to report errors with */ protected final int getTabWidth() { return tabWidth; } /** * Set the tab width to report errors with. * @param tabWidth an {@code int} value */ public final void setTabWidth(int tabWidth) { this.tabWidth = tabWidth; } @Override public final void log(int line, String key, Object... args) { messages.add(new LocalizedMessage(line, getMessageBundle(), key, args, getSeverityLevel(), getId(), getClass(), getCustomMessages().get(key))); } @Override public final void log(int lineNo, int colNo, String key, Object... args) { final int col = 1 + CommonUtils.lengthExpandedTabs(getLines()[lineNo - 1], colNo, tabWidth); messages.add(new LocalizedMessage(lineNo, col, getMessageBundle(), key, args, getSeverityLevel(), getId(), getClass(), getCustomMessages().get(key))); } }