////////////////////////////////////////////////////////////////////////////////
// checkstyle: Checks Java source code for adherence to a set of rules.
// Copyright (C) 2001-2008 Oliver Burn
//
// 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;
import com.google.common.collect.Sets;
import com.puppycrawl.tools.checkstyle.api.AbstractLoader;
import com.puppycrawl.tools.checkstyle.api.CheckstyleException;
import com.puppycrawl.tools.checkstyle.api.FastStack;
import java.io.BufferedInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.util.Enumeration;
import java.util.Set;
import javax.xml.parsers.ParserConfigurationException;
import org.xml.sax.Attributes;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
/**
* Loads a list of package names from a package name XML file.
* @author Rick Giles
* @version 4-Dec-2002
*/
public final class PackageNamesLoader
extends AbstractLoader
{
/** the public ID for the configuration dtd */
private static final String DTD_PUBLIC_ID =
"-//Puppy Crawl//DTD Package Names 1.0//EN";
/** the resource for the configuration dtd */
private static final String DTD_RESOURCE_NAME =
"com/puppycrawl/tools/checkstyle/packages_1_0.dtd";
/** Name of default checkstyle package names resource file.
* The file must be in the classpath.
*/
private static final String CHECKSTYLE_PACKAGES =
"checkstyle_packages.xml";
/** The temporary stack of package name parts */
private final FastStack<String> mPackageStack = FastStack.newInstance();
/** The fully qualified package names. */
private final Set<String> mPackageNames = Sets.newLinkedHashSet();
/**
* Creates a new <code>PackageNamesLoader</code> instance.
* @throws ParserConfigurationException if an error occurs
* @throws SAXException if an error occurs
*/
private PackageNamesLoader()
throws ParserConfigurationException, SAXException
{
super(DTD_PUBLIC_ID, DTD_RESOURCE_NAME);
}
/**
* Returns the set of fully qualified package names this
* this loader processed.
* @return the set of package names
*/
private Set<String> getPackageNames()
{
return mPackageNames;
}
@Override
public void startElement(String aNamespaceURI,
String aLocalName,
String aQName,
Attributes aAtts)
throws SAXException
{
if ("package".equals(aQName)) {
//push package name
final String name = aAtts.getValue("name");
if (name == null) {
throw new SAXException("missing package name");
}
mPackageStack.push(name);
}
}
/**
* Creates a full package name from the package names on the stack.
* @return the full name of the current package.
*/
private String getPackageName()
{
final StringBuffer buf = new StringBuffer();
for (String subPackage : mPackageStack) {
buf.append(subPackage);
if (!subPackage.endsWith(".")) {
buf.append(".");
}
}
return buf.toString();
}
@Override
public void endElement(String aNamespaceURI,
String aLocalName,
String aQName)
{
if ("package".equals(aQName)) {
mPackageNames.add(getPackageName());
mPackageStack.pop();
}
}
/**
* Returns the set of package names, compiled from all
* checkstyle_packages.xml files found on the given classloaders
* classpath.
* @param aClassLoader the class loader for loading the
* checkstyle_packages.xml files.
* @return the set of package names.
* @throws CheckstyleException if an error occurs.
*/
public static Set<String> getPackageNames(ClassLoader aClassLoader)
throws CheckstyleException
{
Enumeration<URL> packageFiles = null;
try {
packageFiles = aClassLoader.getResources(CHECKSTYLE_PACKAGES);
}
catch (IOException e) {
throw new CheckstyleException(
"unable to get package file resources", e);
}
//create the loader outside the loop to prevent PackageObjectFactory
//being created anew for each file
final PackageNamesLoader namesLoader = newPackageNamesLoader();
while ((null != packageFiles) && packageFiles.hasMoreElements()) {
final URL aPackageFile = packageFiles.nextElement();
InputStream stream = null;
try {
stream = new BufferedInputStream(aPackageFile.openStream());
final InputSource source = new InputSource(stream);
loadPackageNamesSource(source, "default package names",
namesLoader);
}
catch (IOException e) {
throw new CheckstyleException(
"unable to open " + aPackageFile, e);
}
finally {
if (stream != null) {
try {
stream.close();
}
catch (IOException e) {
throw new CheckstyleException(
"error closing stream", e);
}
}
}
}
return namesLoader.getPackageNames();
}
/**
* Creates a PackageNamesLoader instance.
* @return the PackageNamesLoader
* @throws CheckstyleException if the creation failed
*/
private static PackageNamesLoader newPackageNamesLoader()
throws CheckstyleException
{
try {
return new PackageNamesLoader();
}
catch (final ParserConfigurationException e) {
throw new CheckstyleException(
"unable to create PackageNamesLoader ", e);
}
catch (final SAXException e) {
throw new CheckstyleException(
"unable to create PackageNamesLoader - "
+ e.getMessage(), e);
}
}
/**
* Returns the list of package names in a specified source.
* @param aSource the source for the list.
* @param aSourceName the name of the source.
* @param aNameLoader the PackageNamesLoader instance
* @throws CheckstyleException if an error occurs.
*/
private static void loadPackageNamesSource(
InputSource aSource, String aSourceName,
PackageNamesLoader aNameLoader)
throws CheckstyleException
{
try {
aNameLoader.parseInputSource(aSource);
}
catch (final SAXException e) {
throw new CheckstyleException("unable to parse "
+ aSourceName + " - " + e.getMessage(), e);
}
catch (final IOException e) {
throw new CheckstyleException("unable to read " + aSourceName, e);
}
}
}