org.xwiki.extension.xar.internal.handler.packager.xml.AbstractHandler.java Source code

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Here is the source code for org.xwiki.extension.xar.internal.handler.packager.xml.AbstractHandler.java

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/*
 * See the NOTICE file distributed with this work for additional
 * information regarding copyright ownership.
 *
 * This 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 software 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 software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package org.xwiki.extension.xar.internal.handler.packager.xml;

import java.lang.reflect.Method;
import java.util.HashSet;
import java.util.Set;

import javax.inject.Inject;

import org.apache.commons.lang3.StringUtils;
import org.xml.sax.Attributes;
import org.xml.sax.ContentHandler;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;
import org.xwiki.component.manager.ComponentLookupException;
import org.xwiki.component.manager.ComponentManager;
import org.xwiki.context.Execution;
import org.xwiki.context.ExecutionContext;

import com.xpn.xwiki.XWikiContext;

public class AbstractHandler extends DefaultHandler {
    @Inject
    private ComponentManager componentManager;

    private Object currentBean;

    private ContentHandler currentHandler;

    private int currentHandlerLevel;

    private int depth = 0;

    protected StringBuffer value;

    protected Set<String> skippedElements = new HashSet<String>();

    protected Set<String> supportedElements;

    public AbstractHandler(ComponentManager componentManager) {
        this.componentManager = componentManager;
    }

    public AbstractHandler(ComponentManager componentManager, Object currentBean) {
        this(componentManager);

        this.currentBean = currentBean;
    }

    protected ComponentManager getComponentManager() {
        return componentManager;
    }

    protected Object getCurrentBean() {
        return currentBean;
    }

    protected void setCurrentBean(Object currentBean) {
        this.currentBean = currentBean;
    }

    protected void addsupportedElements(String supportedElement) {
        if (this.supportedElements == null) {
            this.supportedElements = new HashSet<String>();
        }

        this.supportedElements.add(supportedElement);
    }

    public boolean isSupported(String elementName) {
        return !this.skippedElements.contains(elementName)
                && (this.supportedElements == null || this.supportedElements.contains(elementName));
    }

    // ContentHandler

    @Override
    public void startElement(String uri, String localName, String qName, Attributes attributes)
            throws SAXException {
        if (this.currentHandler == null) {
            if (this.depth == 0) {
                startHandlerElement(uri, localName, qName, attributes);
            } else if (this.depth == 1) {
                startElementInternal(uri, localName, qName, attributes);
            }
        }

        if (this.currentHandler != null) {
            this.currentHandler.startElement(uri, localName, qName, attributes);
        }

        ++this.depth;
    }

    @Override
    public void characters(char[] ch, int start, int length) throws SAXException {
        if (this.currentHandler != null) {
            this.currentHandler.characters(ch, start, length);
        } else if (this.depth == 2) {
            charactersInternal(ch, start, length);
        }
    }

    @Override
    public void endElement(String uri, String localName, String qName) throws SAXException {
        --this.depth;

        if (this.currentHandler != null) {
            this.currentHandler.endElement(uri, localName, qName);

            if (this.depth == this.currentHandlerLevel) {
                endElementInternal(uri, localName, qName);
                this.currentHandler = null;
            }
        } else {
            if (this.depth == 0) {
                endHandlerElement(uri, localName, qName);
            } else if (this.depth == 1) {
                endElementInternal(uri, localName, qName);
            }
        }
    }

    // to override

    protected void startElementInternal(String uri, String localName, String qName, Attributes attributes)
            throws SAXException {
        if (isSupported(qName)) {
            if (this.value == null) {
                this.value = new StringBuffer();
            } else {
                this.value.setLength(0);
            }
        }
    }

    protected void charactersInternal(char[] ch, int start, int length) throws SAXException {
        if (this.currentBean != null && this.value != null) {
            this.value.append(ch, start, length);
        }
    }

    protected void endElementInternal(String uri, String localName, String qName) throws SAXException {
        if (this.currentBean != null && this.value != null) {
            Method setter;
            try {
                setter = this.currentBean.getClass().getMethod("set" + StringUtils.capitalize(qName), String.class);
                setter.invoke(this.currentBean, this.value.toString());
                currentBeanModified();
            } catch (Exception e) {
                // TODO: LOG warn "Unknown element [" + qName + "]"
            }
        }
    }

    protected void currentBeanModified() {
        // no op
    }

    protected void startHandlerElement(String uri, String localName, String qName, Attributes attributes)
            throws SAXException {
        // no op
    }

    protected void endHandlerElement(String uri, String localName, String qName) throws SAXException {
        // no op
    }

    // tools

    protected void setCurrentHandler(ContentHandler currentHandler) {
        this.currentHandler = currentHandler;
        this.currentHandlerLevel = this.depth;
    }

    public ContentHandler getCurrentHandler() {
        return this.currentHandler;
    }

    protected ExecutionContext getExecutionContext() throws ComponentLookupException {
        return this.componentManager.lookup(Execution.class).getContext();
    }

    protected XWikiContext getXWikiContext() throws ComponentLookupException {
        return (XWikiContext) getExecutionContext().getProperty("xwikicontext");
    }
}