////////////////////////////////////////////////////////////////////////////////
// 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.header;
import java.io.BufferedInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.LineNumberReader;
import java.io.Reader;
import java.io.StringReader;
import java.io.UnsupportedEncodingException;
import java.net.URI;
import java.nio.charset.Charset;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Set;
import java.util.regex.Pattern;
import com.google.common.io.Closeables;
import com.puppycrawl.tools.checkstyle.api.AbstractFileSetCheck;
import com.puppycrawl.tools.checkstyle.api.CheckstyleException;
import com.puppycrawl.tools.checkstyle.api.ExternalResourceHolder;
import com.puppycrawl.tools.checkstyle.utils.CommonUtils;
/**
* Abstract super class for header checks.
* Provides support for header and headerFile properties.
* @author o_sukhosolsky
*/
public abstract class AbstractHeaderCheck extends AbstractFileSetCheck
implements ExternalResourceHolder {
/** Pattern to detect occurrences of '\n' in text. */
private static final Pattern ESCAPED_LINE_FEED_PATTERN = Pattern.compile("\\\\n");
/** The lines of the header file. */
private final List<String> readerLines = new ArrayList<>();
/** The file that contains the header to check against. */
private URI headerFile;
/** Name of a charset to use for loading the header from a file. */
private String charset = System.getProperty("file.encoding", "UTF-8");
/**
* Hook method for post processing header lines.
* This implementation does nothing.
*/
protected abstract void postProcessHeaderLines();
/**
* Return the header lines to check against.
* @return the header lines to check against.
*/
protected List<String> getHeaderLines() {
final List<String> copy = new ArrayList<>(readerLines);
return Collections.unmodifiableList(copy);
}
/**
* Set the charset to use for loading the header from a file.
* @param charset the charset to use for loading the header from a file
* @throws UnsupportedEncodingException if charset is unsupported
*/
public void setCharset(String charset) throws UnsupportedEncodingException {
if (!Charset.isSupported(charset)) {
final String message = "unsupported charset: '" + charset + "'";
throw new UnsupportedEncodingException(message);
}
this.charset = charset;
}
/**
* Set the header file to check against.
* @param uri the uri of the header to load.
* @throws CheckstyleException if fileName is empty.
*/
public void setHeaderFile(URI uri) throws CheckstyleException {
if (uri == null) {
throw new CheckstyleException(
"property 'headerFile' is missing or invalid in module "
+ getConfiguration().getName());
}
headerFile = uri;
}
/**
* Load the header from a file.
* @throws CheckstyleException if the file cannot be loaded
*/
private void loadHeaderFile() throws CheckstyleException {
checkHeaderNotInitialized();
Reader headerReader = null;
try {
headerReader = new InputStreamReader(new BufferedInputStream(
headerFile.toURL().openStream()), charset);
loadHeader(headerReader);
}
catch (final IOException ex) {
throw new CheckstyleException(
"unable to load header file " + headerFile, ex);
}
finally {
Closeables.closeQuietly(headerReader);
}
}
/**
* Called before initializing the header.
* @throws IllegalArgumentException if header has already been set
*/
private void checkHeaderNotInitialized() {
if (!readerLines.isEmpty()) {
throw new IllegalArgumentException(
"header has already been set - "
+ "set either header or headerFile, not both");
}
}
/**
* Set the header to check against. Individual lines in the header
* must be separated by '\n' characters.
* @param header header content to check against.
* @throws IllegalArgumentException if the header cannot be interpreted
*/
public void setHeader(String header) {
if (!CommonUtils.isBlank(header)) {
checkHeaderNotInitialized();
final String headerExpandedNewLines = ESCAPED_LINE_FEED_PATTERN
.matcher(header).replaceAll("\n");
final Reader headerReader = new StringReader(headerExpandedNewLines);
try {
loadHeader(headerReader);
}
catch (final IOException ex) {
throw new IllegalArgumentException("unable to load header", ex);
}
finally {
Closeables.closeQuietly(headerReader);
}
}
}
/**
* Load header to check against from a Reader into readerLines.
* @param headerReader delivers the header to check against
* @throws IOException if
*/
private void loadHeader(final Reader headerReader) throws IOException {
readerLines.clear();
final LineNumberReader lnr = new LineNumberReader(headerReader);
while (true) {
final String line = lnr.readLine();
if (line == null) {
break;
}
readerLines.add(line);
}
postProcessHeaderLines();
}
@Override
protected final void finishLocalSetup() throws CheckstyleException {
if (headerFile != null) {
loadHeaderFile();
}
if (readerLines.isEmpty()) {
setHeader(null);
}
}
@Override
public Set<String> getExternalResourceLocations() {
final Set<String> result;
if (headerFile == null) {
result = Collections.emptySet();
}
else {
result = Collections.singleton(headerFile.toString());
}
return result;
}
}