import com.sun.org.apache.xerces.internal.util.EntityResolverWrapper; //导入依赖的package包/类
/**
 * Return the current entity resolver.
 *
 * @return The current entity resolver, or null if none
 *         has been registered.
 * @see #setEntityResolver
 */
public EntityResolver getEntityResolver() {

    EntityResolver entityResolver = null;
    try {
        XMLEntityResolver xmlEntityResolver =
            (XMLEntityResolver)fConfiguration.getProperty(ENTITY_RESOLVER);
        if (xmlEntityResolver != null) {
            if (xmlEntityResolver instanceof EntityResolverWrapper) {
                entityResolver =
                    ((EntityResolverWrapper) xmlEntityResolver).getEntityResolver();
            }
            else if (xmlEntityResolver instanceof EntityResolver2Wrapper) {
                entityResolver =
                    ((EntityResolver2Wrapper) xmlEntityResolver).getEntityResolver();
            }
        }
    }
    catch (XMLConfigurationException e) {
        // do nothing
    }
    return entityResolver;

}
 

import com.sun.org.apache.xerces.internal.util.EntityResolverWrapper; //导入依赖的package包/类
/**
 * Sets the resolver used to resolve external entities. The EntityResolver
 * interface supports resolution of public and system identifiers.
 *
 * @param resolver The new entity resolver. Passing a null value will
 *                 uninstall the currently installed resolver.
 */
public void setEntityResolver(EntityResolver resolver) {

    try {
        XMLEntityResolver xer = (XMLEntityResolver) fConfiguration.getProperty(ENTITY_RESOLVER);
        if (fUseEntityResolver2 && resolver instanceof EntityResolver2) {
            if (xer instanceof EntityResolver2Wrapper) {
                EntityResolver2Wrapper er2w = (EntityResolver2Wrapper) xer;
                er2w.setEntityResolver((EntityResolver2) resolver);
            }
            else {
                fConfiguration.setProperty(ENTITY_RESOLVER,
                        new EntityResolver2Wrapper((EntityResolver2) resolver));
            }
        }
        else {
            if (xer instanceof EntityResolverWrapper) {
                EntityResolverWrapper erw = (EntityResolverWrapper) xer;
                erw.setEntityResolver(resolver);
            }
            else {
                fConfiguration.setProperty(ENTITY_RESOLVER,
                        new EntityResolverWrapper(resolver));
            }
        }
    }
    catch (XMLConfigurationException e) {
        // do nothing
    }

}