Glassfish example source code file (InstanceReaderFilter.java)

This example Glassfish source code file (InstanceReaderFilter.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Glassfish tags/keywords

domainxmlpreparser, domainxmlpreparserexception, instancereaderfilter, instancereaderfilter, io, log, logging, name, name, net, network, override, serverreaderfilter, string, string, url, util, xmlstreamexception, xmlstreamexception, xmlstreamreader

The Glassfish InstanceReaderFilter.java source code

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 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
 * or packager/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
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 * file and include the License file at packager/legal/LICENSE.txt.
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 * GPL Classpath Exception:
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 * exception as provided by Oracle in the GPL Version 2 section of the License
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package org.glassfish.config.support;

import com.sun.enterprise.config.serverbeans.Cluster;
import com.sun.enterprise.config.serverbeans.ServerRef;
import com.sun.enterprise.universal.i18n.LocalStringsImpl;
import com.sun.enterprise.util.EarlyLogger;
import com.sun.enterprise.util.StringUtils;
import java.io.*;
import java.net.*;
import java.util.*;
import java.util.logging.Level;
import javax.xml.stream.XMLInputFactory;
import static javax.xml.stream.XMLStreamConstants.START_ELEMENT;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamReader;
import org.glassfish.config.support.DomainXmlPreParser.DomainXmlPreParserException;
import org.jvnet.hk2.component.Habitat;
import static org.glassfish.config.support.Constants.*;

/**
 * The "pre-parser" goes through the domain.xml and finds all the 'special'
 * elements that should be retained.  This filter class just checks the elements
 * against those lists...
 * @author Byron Nevins
 */
class InstanceReaderFilter extends ServerReaderFilter {

    InstanceReaderFilter(String theServerName, Habitat theHabitat, URL theDomainXml,
            XMLInputFactory theXif) throws XMLStreamException, DomainXmlPreParserException {

        super(theHabitat, theDomainXml, theXif);
        instanceName = theServerName;
        dxpp = new DomainXmlPreParser(domainXml, xif, instanceName);
    }

    /**
     * This method is called for every element.  We are very interested
     * in server, config and cluster.
     * We will only filter out config and server and cluster elements never other elements
     * We use this as a handy hook to get info about other elements -- which really
     * is a side-effect.
     *
     * @return true to NOT parse this sub-tree
     * @throws XMLStreamException
     */
    @Override
    final boolean filterOut() throws XMLStreamException {
        try {
            XMLStreamReader reader = getParent();
            String elementName = reader.getLocalName();

            if (!StringUtils.ok(elementName))
                return true; // famous last words:  "this can never happen" ;-)

            // possibly filter out from these 3 kinds of elements
            if (elementName.equals(SERVER))
                return handleServer(reader);

            if (elementName.equals(CONFIG))
                return handleConfig(reader);

            if (elementName.equals(CLUSTER))
                return handleCluster(reader);

            // keep everything else
            return false;
        }
        catch (Exception e) {
            // I don't trust the XML parser code in the JDK -- it likes to throw
            // unchecked exceptions!!
            throw new XMLStreamException(
                    Strings.get("InstanceReaderFilter.UnknownException",
                    e.toString()), e);
        }
    }

    @Override
    final String configWasFound() {
        // preparser already threw an exception if the config wasn't found
        return null;
    }

    /**
     * @return true if we want to filter out this server element
     */
    private boolean handleServer(XMLStreamReader r) {
        String name = r.getAttributeValue(null, NAME);

        if (StringUtils.ok(name) && dxpp.getServerNames().contains(name))
            return false;

        return true;
    }

    /**
     * @return true if we want to filter out this config element
     */
    private boolean handleConfig(XMLStreamReader reader) {
        String name = reader.getAttributeValue(null, NAME);

        if (dxpp.getConfigName().equals(name))
            return false;

        return true;
    }

    /**
     * Note that dxpp.getClusterName() will definitely return null
     * for stand-alone instances.  This is normal.
     *
     * @return true if we want to filter out this cluster element
     */
    private boolean handleCluster(XMLStreamReader reader) {
        String name = reader.getAttributeValue(null, NAME);
        String myCluster = dxpp.getClusterName();

        if (StringUtils.ok(myCluster) && myCluster.equals(name))
            return false;

        return true;
    }

    private final DomainXmlPreParser dxpp;
    private final String instanceName;
}