package com.rometools.rome.io.impl;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import org.jdom2.Element;
import org.jdom2.Namespace;
import org.jdom2.Parent;
import com.rometools.rome.feed.module.Module;
import com.rometools.rome.io.WireFeedGenerator;
/**
* @author Alejandro Abdelnur
*/
public abstract class BaseWireFeedGenerator implements WireFeedGenerator {
/**
* [TYPE].feed.ModuleParser.classes= [className] ...
*/
private static final String FEED_MODULE_GENERATORS_POSFIX_KEY = ".feed.ModuleGenerator.classes";
/**
* [TYPE].item.ModuleParser.classes= [className] ...
*/
private static final String ITEM_MODULE_GENERATORS_POSFIX_KEY = ".item.ModuleGenerator.classes";
/**
* [TYPE].person.ModuleParser.classes= [className] ...
*/
private static final String PERSON_MODULE_GENERATORS_POSFIX_KEY = ".person.ModuleGenerator.classes";
private final String type;
private final ModuleGenerators feedModuleGenerators;
private final ModuleGenerators itemModuleGenerators;
private final ModuleGenerators personModuleGenerators;
private final Namespace[] allModuleNamespaces;
protected BaseWireFeedGenerator(final String type) {
this.type = type;
feedModuleGenerators = new ModuleGenerators(type + FEED_MODULE_GENERATORS_POSFIX_KEY, this);
itemModuleGenerators = new ModuleGenerators(type + ITEM_MODULE_GENERATORS_POSFIX_KEY, this);
personModuleGenerators = new ModuleGenerators(type + PERSON_MODULE_GENERATORS_POSFIX_KEY, this);
final Set<Namespace> allModuleNamespaces = new HashSet<Namespace>();
for (final Namespace namespace : feedModuleGenerators.getAllNamespaces()) {
allModuleNamespaces.add(namespace);
}
for (final Namespace namespace : itemModuleGenerators.getAllNamespaces()) {
allModuleNamespaces.add(namespace);
}
for (final Namespace namespace : personModuleGenerators.getAllNamespaces()) {
allModuleNamespaces.add(namespace);
}
this.allModuleNamespaces = new Namespace[allModuleNamespaces.size()];
allModuleNamespaces.toArray(this.allModuleNamespaces);
}
@Override
public String getType() {
return type;
}
protected void generateModuleNamespaceDefs(final Element root) {
for (final Namespace allModuleNamespace : allModuleNamespaces) {
root.addNamespaceDeclaration(allModuleNamespace);
}
}
protected void generateFeedModules(final List<Module> modules, final Element feed) {
feedModuleGenerators.generateModules(modules, feed);
}
public void generateItemModules(final List<Module> modules, final Element item) {
itemModuleGenerators.generateModules(modules, item);
}
public void generatePersonModules(final List<Module> modules, final Element person) {
personModuleGenerators.generateModules(modules, person);
}
protected void generateForeignMarkup(final Element element, final List<Element> foreignElements) {
if (foreignElements != null) {
for (final Element foreignElement : foreignElements) {
final Parent parent = foreignElement.getParent();
if (parent != null) {
parent.removeContent(foreignElement);
}
element.addContent(foreignElement);
}
}
}
/**
* Purging unused declarations is less optimal, performance-wise, than never adding them in the
* first place. So, we should still ask the ROME guys to fix their code (not adding dozens of
* unnecessary module declarations). Having said that: purging them here, before XML generation,
* is more efficient than parsing and re-molding the XML after ROME generates it.
* <p/>
* Note that the calling app could still add declarations/modules to the Feed tree after this.
* Which is fine. But those modules are then responsible for crawling to the root of the tree,
* at generate() time, to make sure their namespace declarations are present.
*/
protected static void purgeUnusedNamespaceDeclarations(final Element root) {
final Set<String> usedPrefixes = new HashSet<String>();
collectUsedPrefixes(root, usedPrefixes);
final List<Namespace> list = root.getAdditionalNamespaces();
final List<Namespace> additionalNamespaces = new ArrayList<Namespace>();
additionalNamespaces.addAll(list); // the duplication will prevent a
// ConcurrentModificationException
// below
for (final Namespace ns : additionalNamespaces) {
final String prefix = ns.getPrefix();
if (prefix != null && prefix.length() > 0 && !usedPrefixes.contains(prefix)) {
root.removeNamespaceDeclaration(ns);
}
}
}
private static void collectUsedPrefixes(final Element el, final Set<String> collector) {
final String prefix = el.getNamespacePrefix();
if (prefix != null && prefix.length() > 0 && !collector.contains(prefix)) {
collector.add(prefix);
}
final List<Element> kids = el.getChildren();
for (final Element kid : kids) {
// recursion- worth it
collectUsedPrefixes(kid, collector);
}
}
}