CanonicalizerSpi.java

package ru.codeinside.gws.xml.normalizer.normalize.implementations;

import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;
import ru.codeinside.gws.xml.normalizer.normalize.exceptions.CanonicalizationException;
import ru.codeinside.gws.xml.normalizer.normalize.utils.XMLUtils;

import javax.xml.XMLConstants;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import java.io.ByteArrayInputStream;
import java.io.OutputStream;
import java.util.Set;

/**
 * Base class which all Canonicalization algorithms extend.
 *
 * @author Christian Geuer-Pollmann
 */
public abstract class CanonicalizerSpi {

    /**
     * Reset the writer after a c14n
     */
    protected boolean reset = false;

    /**
     * Method canonicalize
     *
     * @param inputBytes
     * @return the c14n bytes.
     * @throws CanonicalizationException
     * @throws java.io.IOException
     * @throws javax.xml.parsers.ParserConfigurationException
     *
     * @throws org.xml.sax.SAXException
     */
    public byte[] engineCanonicalize(byte[] inputBytes)
            throws javax.xml.parsers.ParserConfigurationException, java.io.IOException,
            org.xml.sax.SAXException, CanonicalizationException {

        java.io.InputStream bais = new ByteArrayInputStream(inputBytes);
        InputSource in = new InputSource(bais);
        DocumentBuilderFactory dfactory = DocumentBuilderFactory.newInstance();
        dfactory.setFeature(XMLConstants.FEATURE_SECURE_PROCESSING, Boolean.TRUE);

        // needs to validate for ID attribute normalization
        dfactory.setNamespaceAware(true);

        DocumentBuilder db = dfactory.newDocumentBuilder();

        Document document = db.parse(in);
        return this.engineCanonicalizeSubTree(document);
    }

    /**
     * Method engineCanonicalizeXPathNodeSet
     *
     * @param xpathNodeSet
     * @return the c14n bytes
     * @throws CanonicalizationException
     */
    public byte[] engineCanonicalizeXPathNodeSet(NodeList xpathNodeSet)
            throws CanonicalizationException {
        return this.engineCanonicalizeXPathNodeSet(
                XMLUtils.convertNodelistToSet(xpathNodeSet)
        );
    }

    /**
     * Method engineCanonicalizeXPathNodeSet
     *
     * @param xpathNodeSet
     * @param inclusiveNamespaces
     * @return the c14n bytes
     * @throws CanonicalizationException
     */
    public byte[] engineCanonicalizeXPathNodeSet(NodeList xpathNodeSet, String inclusiveNamespaces)
            throws CanonicalizationException {
        return this.engineCanonicalizeXPathNodeSet(
                XMLUtils.convertNodelistToSet(xpathNodeSet), inclusiveNamespaces
        );
    }

    /**
     * Returns the URI of this engine.
     *
     * @return the URI
     */
    public abstract String engineGetURI();

    /**
     * Returns true if comments are included
     *
     * @return true if comments are included
     */
    public abstract boolean engineGetIncludeComments();

    /**
     * C14n a nodeset
     *
     * @param xpathNodeSet
     * @return the c14n bytes
     * @throws CanonicalizationException
     */
    public abstract byte[] engineCanonicalizeXPathNodeSet(Set<Node> xpathNodeSet)
            throws CanonicalizationException;

    /**
     * C14n a nodeset
     *
     * @param xpathNodeSet
     * @param inclusiveNamespaces
     * @return the c14n bytes
     * @throws CanonicalizationException
     */
    public abstract byte[] engineCanonicalizeXPathNodeSet(
            Set<Node> xpathNodeSet, String inclusiveNamespaces
    ) throws CanonicalizationException;

    /**
     * C14n a node tree.
     *
     * @param rootNode
     * @return the c14n bytes
     * @throws CanonicalizationException
     */
    public abstract byte[] engineCanonicalizeSubTree(Node rootNode)
            throws CanonicalizationException;

    /**
     * C14n a node tree.
     *
     * @param rootNode
     * @param inclusiveNamespaces
     * @return the c14n bytes
     * @throws CanonicalizationException
     */
    public abstract byte[] engineCanonicalizeSubTree(Node rootNode, String inclusiveNamespaces)
            throws CanonicalizationException;

    /**
     * Sets the writer where the canonicalization ends. ByteArrayOutputStream if
     * none is set.
     *
     * @param os
     */
    public abstract void setWriter(OutputStream os);

}