org.xchain.examples.tutorial.TraceChain.java Source code

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Here is the source code for org.xchain.examples.tutorial.TraceChain.java

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/**
 *    Copyright 2011 meltmedia
 *
 *    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.xchain.examples.tutorial;

import static org.xchain.examples.tutorial.TraceUtil.*;
import org.xchain.Locatable;
import org.xchain.annotations.Attribute;
import org.xchain.annotations.AttributeType;
import org.xchain.annotations.Element;
import org.xchain.impl.ChainImpl;
import org.xchain.framework.sax.CommandHandler;
import org.xchain.framework.sax.CommandXmlReader;
import org.xchain.namespaces.sax.PipelineCommand;
import org.apache.commons.jxpath.JXPathContext;
import org.xml.sax.ContentHandler;
import org.xml.sax.Locator;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.AttributesImpl;

/**
 * @author Christian Trimble
 */
@Element(localName = "trace-chain")
public abstract class TraceChain extends ChainImpl {
    private static String XHTML_NAMESPACE_URI = "http://www.w3.org/1999/xhtml";
    private static String DIV_ELEMENT = "div";

    @Attribute(localName = "name", type = AttributeType.ATTRIBUTE_VALUE_TEMPLATE)
    public abstract String getName(JXPathContext context);

    public boolean execute(JXPathContext context) throws Exception {
        // variables for flow control.
        boolean result = false;
        Exception exception = null;

        // get the sax content handler.
        CommandHandler handler = ((CommandXmlReader) PipelineCommand.getPipelineConfig().getXmlReader())
                .getCommandHandler();

        String xhtmlPrefix = xhtmlPrefix(context);
        startExecuteBlock(handler, xhtmlPrefix, getName(context));

        try {
            result = super.execute(context);
        } catch (Exception e) {
            exception = e;
        } finally {
            // if we are not passing a sax exception, then send the output.
            if (exception != null && !(exception instanceof SAXException)) {
                endExecuteBlock(handler, xhtmlPrefix, getName(context), exception);
            }
        }

        if (exception != null) {
            throw exception;
        }

        endExecuteBlock(handler, xhtmlPrefix, getName(context), result);

        return result;
    }

    private static void characters(ContentHandler handler, String text) throws SAXException {
        char[] characters = text.toCharArray();
        handler.characters(characters, 0, characters.length);
    }
}