org.picketlink.common.parsers.AbstractParser Maven / Gradle / Ivy
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*
* Copyright 2013 Red Hat, Inc. and/or its affiliates.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.picketlink.common.parsers;
import org.picketlink.common.PicketLinkLogger;
import org.picketlink.common.PicketLinkLoggerFactory;
import org.picketlink.common.constants.GeneralConstants;
import org.picketlink.common.exceptions.ParsingException;
import org.picketlink.common.util.StaxParserUtil;
import org.picketlink.common.util.SystemPropertiesUtil;
import javax.xml.stream.EventFilter;
import javax.xml.stream.XMLEventReader;
import javax.xml.stream.XMLInputFactory;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.events.Characters;
import javax.xml.stream.events.XMLEvent;
import java.io.InputStream;
import java.security.AccessController;
import java.security.PrivilegedAction;
/**
* Base class for parsers
*
* @author [email protected]
* @since Oct 12, 2010
*/
public abstract class AbstractParser implements ParserNamespaceSupport {
protected static final PicketLinkLogger logger = PicketLinkLoggerFactory.getLogger();
/**
* Get the JAXP {@link XMLInputFactory}
*
* @return
*/
protected XMLInputFactory getXMLInputFactory() {
boolean tccl_jaxp = SystemPropertiesUtil.getSystemProperty(GeneralConstants.TCCL_JAXP, "false")
.equalsIgnoreCase("true");
ClassLoader prevTCCL = getTCCL();
try {
if (tccl_jaxp) {
setTCCL(getClass().getClassLoader());
}
return XMLInputFactory.newInstance();
} finally {
if (tccl_jaxp) {
setTCCL(prevTCCL);
}
}
}
/**
* Parse an InputStream for payload
*
* @param configStream
*
* @return
*
* @throws {@link IllegalArgumentException}
* @throws {@link IllegalArgumentException} when the configStream is null
*/
public Object parse(InputStream configStream) throws ParsingException {
if (configStream == null)
throw logger.nullArgumentError("InputStream");
XMLInputFactory xmlInputFactory = getXMLInputFactory();
XMLEventReader xmlEventReader = StaxParserUtil.getXMLEventReader(configStream);
try {
xmlEventReader = xmlInputFactory.createFilteredReader(xmlEventReader, new EventFilter() {
public boolean accept(XMLEvent xmlEvent) {
// We are going to disregard characters that are new line and whitespace
if (xmlEvent.isCharacters()) {
Characters chars = xmlEvent.asCharacters();
String data = chars.getData();
data = valid(data) ? data.trim() : null;
return valid(data);
} else {
return xmlEvent.isStartElement() || xmlEvent.isEndElement();
}
}
private boolean valid(String str) {
return str != null && str.length() > 0;
}
});
} catch (XMLStreamException e) {
throw logger.parserException(e);
}
return parse(xmlEventReader);
}
private ClassLoader getTCCL() {
if (System.getSecurityManager() != null) {
return AccessController.doPrivileged(new PrivilegedAction() {
public ClassLoader run() {
return Thread.currentThread().getContextClassLoader();
}
});
} else {
return Thread.currentThread().getContextClassLoader();
}
}
private void setTCCL(final ClassLoader paramCl) {
if (System.getSecurityManager() != null) {
AccessController.doPrivileged(new PrivilegedAction() {
public Void run() {
Thread.currentThread().setContextClassLoader(paramCl);
return null;
}
});
} else {
Thread.currentThread().setContextClassLoader(paramCl);
}
}
}