jaxp/src/java.xml/share/classes/javax/xml/catalog/CatalogResolver.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * accompanied this code).
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package javax.xml.catalog;

import org.xml.sax.EntityResolver;
import org.xml.sax.InputSource;

/**
 * A SAX EntityResolver that uses catalogs to resolve references.
 *
 * @since 9
 */
public interface CatalogResolver extends EntityResolver {

    /**
     * The method searches through the catalog entries in the main and
     * alternative catalogs to attempt to find a match with the specified publicId
     * or systemId.
     * <p>
     * For resolving external entities, system entries will be matched before
     * the public entries.
     * <p>
     * <b>The {@code prefer} attribute</b>: if the {@code prefer} is public,
     * and there is no match found through the system entries, public entries
     * will be considered. If it is not specified, the {@code prefer} is public
     * by default (Note that by the OASIS standard, system entries will always
     * be considered first when the external system identifier is specified.
     * Prefer public means that public entries will be matched when both system
     * and public identifiers are specified. In general therefore, prefer
     * public is recommended.)
     *
     * @param publicId the public identifier of the external entity being
     * referenced, or null if none was supplied
     *
     * @param systemId the system identifier of the external entity being
     * referenced. A system identifier is required on all external entities. XML
     * requires a system identifier on all external entities, so this value is
     * always specified.
     *
     * @return a {@link org.xml.sax.InputSource} object if a mapping is found. If no mapping is
     * found, returns a {@link org.xml.sax.InputSource} object containing an empty
     * {@link java.io.Reader} if the {@code javax.xml.catalog.resolve} property
     * is set to {@code ignore}; returns null if the
     * {@code javax.xml.catalog.resolve} property is set to {@code continue}.
     *
     * @throws CatalogException if no mapping is found and
     * {@code javax.xml.catalog.resolve} is specified as strict
     */
    @Override
    public InputSource resolveEntity(String publicId, String systemId);
}