LoopExtension.java

1_LoopExtension.java

package com.experimental;

import java.util.Stack;

import nu.xom.Attribute;
import nu.xom.Document;
import nu.xom.Element;
import nu.xom.Elements;

import org.concordion.api.Evaluator;
import org.concordion.api.extension.ConcordionExtender;
import org.concordion.api.extension.ConcordionExtension;
import org.concordion.api.listener.DocumentParsingListener;
import org.concordion.internal.SimpleEvaluator;
import org.concordion.internal.util.Check;

public class LoopExtension implements ConcordionExtension, DocumentParsingListener {

	public static final String EXTENSION_NAMESPACE = "urn:concordion-extensions:2010";
	public static final String COMMAND_NAME = "loop";
	private final Evaluator evaluator;

	@Override
	public void addTo(final ConcordionExtender concordionExtender) {
		concordionExtender.withDocumentParsingListener(this);
	}

	public LoopExtension(Object fixture) {
		evaluator = new SimpleEvaluator(fixture);
	}

	@Override
	public void beforeParsing(Document document) {
		Stack<Element> all = new Stack<Element>();
		all.add(document.getRootElement());
		while(!all.isEmpty()) {
			Element parent = all.pop();
			Elements children = parent.getChildElements();
			for (int i = 0; i < children.size(); i++) {
				Element child = children.get(i);
				Attribute attr = child.getAttribute(COMMAND_NAME, EXTENSION_NAMESPACE);
				if (attr == null) {
					all.add(child);
				} else {
					String expression = attr.getValue();
					Object result = evaluator.evaluate(expression);
					Check.isTrue(result != null && result instanceof Integer,
							"Loop extension expects an expression evaluated to Integer: " + expression);
					int times = (Integer) result;
					child.removeAttribute(attr);
					int index = parent.indexOf(child);
					for (int j = 0; j < times; j++) {
						parent.insertChild(new Element(child), index + 1);
					}
					child.detach();
				}
			}
		}
	}

}

2_AttributeExtension.java

package com.experimental;

import org.concordion.api.AbstractCommand;
import org.concordion.api.CommandCall;
import org.concordion.api.Evaluator;
import org.concordion.api.ResultRecorder;
import org.concordion.api.extension.ConcordionExtender;
import org.concordion.api.extension.ConcordionExtension;
import org.concordion.internal.util.Check;

public class AttributeExtension extends AbstractCommand implements ConcordionExtension {

	public static final String EXTENSION_NAMESPACE = "urn:concordion-extensions:2010";
	public static final String COMMAND_NAME = "attribute";

	@Override
	public void addTo(final ConcordionExtender concordionExtender) {
		concordionExtender.withCommand(EXTENSION_NAMESPACE, COMMAND_NAME, this);
	}

	@Override
	public void verify(CommandCall commandCall, Evaluator evaluator, ResultRecorder resultRecorder) {
		String expressions = commandCall.getExpression();
		for (String expression : expressions.split(",")) {
			int pos = expression.indexOf("=");
			Check.isTrue(pos >= 0, "Must have attributeName=attributeValue");
			String attributeName = expression.substring(0, pos);
			String attributeExpression = expression.substring(pos + 1);
			String result = evaluator.evaluate(attributeExpression).toString();
			if (result != null && !result.isEmpty()) {
				commandCall.getElement().addAttribute(attributeName, result);
			}
		}
		commandCall.getChildren().processSequentially(evaluator, resultRecorder);
	}
}