/*
* Copyright 2004 Sun Microsystems, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
package com.sun.syndication.io.impl;
import com.sun.syndication.feed.WireFeed;
import com.sun.syndication.feed.rss.*;
import com.sun.syndication.io.FeedException;
import org.jdom.Document;
import org.jdom.Element;
import org.jdom.Namespace;
import java.util.List;
/**
* Feed Generator for RSS 0.90
* <p/>
*
* @author Elaine Chien
*/
public class RSS090Generator extends BaseWireFeedGenerator {
private static final String RDF_URI = "http://www.w3.org/1999/02/22-rdf-syntax-ns#";
private static final String RSS_URI = "http://my.netscape.com/rdf/simple/0.9/";
private static final String CONTENT_URI = "http://purl.org/rss/1.0/modules/content/";
private static final Namespace RDF_NS = Namespace.getNamespace("rdf", RDF_URI);
private static final Namespace RSS_NS = Namespace.getNamespace(RSS_URI);
private static final Namespace CONTENT_NS = Namespace.getNamespace("content", CONTENT_URI);
public RSS090Generator() {
this("rss_0.9");
}
protected RSS090Generator(String type) {
super(type);
}
public Document generate(WireFeed feed) throws FeedException {
Channel channel = (Channel)feed;
Element root = createRootElement(channel);
populateFeed(channel,root);
purgeUnusedNamespaceDeclarations(root);
return createDocument(root);
}
protected Namespace getFeedNamespace() {
return RSS_NS;
}
protected Namespace getRDFNamespace() {
return RDF_NS;
}
protected Namespace getContentNamespace() {
return CONTENT_NS;
}
protected Document createDocument(Element root) {
return new Document(root);
}
protected Element createRootElement(Channel channel) {
Element root = new Element("RDF",getRDFNamespace());
root.addNamespaceDeclaration(getFeedNamespace());
root.addNamespaceDeclaration(getRDFNamespace());
root.addNamespaceDeclaration(getContentNamespace());
generateModuleNamespaceDefs(root);
return root;
}
protected void populateFeed(Channel channel, Element parent) throws FeedException {
addChannel(channel,parent);
addImage(channel,parent);
addTextInput(channel,parent);
addItems(channel,parent);
generateForeignMarkup(parent, (List)channel.getForeignMarkup());
}
protected void addChannel(Channel channel,Element parent) throws FeedException {
Element eChannel = new Element("channel", getFeedNamespace());
populateChannel(channel,eChannel);
checkChannelConstraints(eChannel);
parent.addContent(eChannel);
generateFeedModules(channel.getModules(),eChannel);
}
/**
* Populates the given channel with parsed data from the ROME element that holds the
* channel data.
*
* @param channel the channel into which parsed data will be added.
* @param eChannel the XML element that holds the data for the channel.
*/
protected void populateChannel(Channel channel,Element eChannel) {
String title = channel.getTitle();
if (title!=null) {
eChannel.addContent(generateSimpleElement("title",title));
}
String link = channel.getLink();
if (link!=null) {
eChannel.addContent(generateSimpleElement("link",link));
}
String description = channel.getDescription();
if (description!=null) {
eChannel.addContent(generateSimpleElement("description",description));
}
}
// maxLen == -1 means unlimited.
protected void checkNotNullAndLength(Element parent, String childName, int minLen, int maxLen) throws FeedException {
Element child = parent.getChild(childName,getFeedNamespace());
if (child == null) {
throw new FeedException("Invalid "+getType()+" feed, missing "+parent.getName()+" "+childName);
}
checkLength(parent,childName,minLen,maxLen);
}
// maxLen == -1 means unlimited.
protected void checkLength(Element parent, String childName, int minLen, int maxLen) throws FeedException {
Element child = parent.getChild(childName,getFeedNamespace());
if (child != null) {
if (minLen>0 && child.getText().length()<minLen) {
throw new FeedException("Invalid "+getType()+" feed, "+parent.getName()+" "+childName + "short of "+minLen+" length");
}
if (maxLen>-1 && child.getText().length()>maxLen) {
throw new FeedException("Invalid "+getType()+" feed, "+parent.getName()+" "+childName + "exceeds "+maxLen+" length");
}
}
}
protected void addImage(Channel channel,Element parent) throws FeedException {
Image image = channel.getImage();
if (image!=null) {
Element eImage = new Element("image", getFeedNamespace());
populateImage(image,eImage);
checkImageConstraints(eImage);
parent.addContent(eImage);
}
}
protected void populateImage(Image image,Element eImage) {
String title = image.getTitle();
if (title!=null) {
eImage.addContent(generateSimpleElement("title",title));
}
String url = image.getUrl();
if (url!=null) {
eImage.addContent(generateSimpleElement("url",url));
}
String link = image.getLink();
if (link!=null) {
eImage.addContent(generateSimpleElement("link",link));
}
}
// Thxs DW for this one
protected String getTextInputLabel() {
return "textInput";
}
protected void addTextInput(Channel channel,Element parent) throws FeedException {
TextInput textInput = channel.getTextInput();
if (textInput!=null) {
Element eTextInput = new Element(getTextInputLabel(), getFeedNamespace());
populateTextInput(textInput,eTextInput);
checkTextInputConstraints(eTextInput);
parent.addContent(eTextInput);
}
}
protected void populateTextInput(TextInput textInput,Element eTextInput) {
String title = textInput.getTitle();
if (title!=null) {
eTextInput.addContent(generateSimpleElement("title",title));
}
String description = textInput.getDescription();
if (description!=null) {
eTextInput.addContent(generateSimpleElement("description",description));
}
String name = textInput.getName();
if (name!=null) {
eTextInput.addContent(generateSimpleElement("name",name));
}
String link = textInput.getLink();
if (link!=null) {
eTextInput.addContent(generateSimpleElement("link",link));
}
}
protected void addItems(Channel channel,Element parent) throws FeedException {
List items = channel.getItems();
for (int i=0;i<items.size();i++) {
addItem((Item)items.get(i),parent, i);
}
checkItemsConstraints(parent);
}
protected void addItem(Item item, Element parent, int index) throws FeedException {
Element eItem = new Element("item", getFeedNamespace());
populateItem(item,eItem, index);
checkItemConstraints(eItem);
generateItemModules(item.getModules(),eItem);
parent.addContent(eItem);
}
protected void populateItem(Item item, Element eItem, int index) {
String title = item.getTitle();
if (title!=null) {
eItem.addContent(generateSimpleElement("title",title));
}
String link = item.getLink();
if (link!=null) {
eItem.addContent(generateSimpleElement("link",link));
}
generateForeignMarkup(eItem, (List)item.getForeignMarkup());
}
protected Element generateSimpleElement(String name, String value) {
Element element = new Element(name, getFeedNamespace());
element.addContent(value);
return element;
}
protected void checkChannelConstraints(Element eChannel) throws FeedException {
checkNotNullAndLength(eChannel,"title", 0, 40);
checkNotNullAndLength(eChannel,"description", 0, 500);
checkNotNullAndLength(eChannel,"link", 0, 500);
}
protected void checkImageConstraints(Element eImage) throws FeedException {
checkNotNullAndLength(eImage,"title", 0, 40);
checkNotNullAndLength(eImage,"url", 0, 500);
checkNotNullAndLength(eImage,"link", 0, 500);
}
protected void checkTextInputConstraints(Element eTextInput) throws FeedException {
checkNotNullAndLength(eTextInput,"title", 0, 40);
checkNotNullAndLength(eTextInput,"description", 0, 100);
checkNotNullAndLength(eTextInput,"name", 0, 500);
checkNotNullAndLength(eTextInput,"link", 0, 500);
}
protected void checkItemsConstraints(Element parent) throws FeedException {
int count = parent.getChildren("item",getFeedNamespace()).size();
if (count<1 || count>15) {
throw new FeedException("Invalid "+getType()+" feed, item count is "+count+" it must be between 1 an 15");
}
}
protected void checkItemConstraints(Element eItem) throws FeedException {
checkNotNullAndLength(eItem,"title", 0, 100);
checkNotNullAndLength(eItem,"link", 0, 500);
}
}