/* Copyright (c) 2008 Google 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.google.gdata.data;
import com.google.gdata.util.common.xml.XmlWriter;
import com.google.gdata.util.Namespaces;
import com.google.gdata.util.ParseException;
import com.google.gdata.util.XmlBlob;
import com.google.gdata.util.XmlParser;
import com.google.gdata.util.common.html.HtmlToText;
import java.io.IOException;
import java.io.StringWriter;
import java.util.ArrayList;
/**
* XHTML variant of {@link TextConstruct}.
*
*
*/
public class XhtmlTextConstruct extends TextConstruct {
/** Class constructor. */
public XhtmlTextConstruct() {}
/**
* Class constructor specifying the XHTML content for this
* text construct to contain.
*/
public XhtmlTextConstruct(XmlBlob xhtml) {
this.xhtml = xhtml;
}
/**
* Class constructor specifying the XHTML content for this
* text construct to contain, plus the human language that
* the text is written in.
*/
public XhtmlTextConstruct(XmlBlob xhtml, String lang) {
this.xhtml = xhtml;
this.lang = lang;
}
/** @return the type (XHTML) of this text construct */
@Override
public int getType() { return Type.XHTML; }
/** @return {@code true} if this text construct has no contents */
@Override
public boolean isEmpty() { return xhtml == null; }
/** XHTML contents. */
protected XmlBlob xhtml;
/** @return the XHTML contents of this text construct */
public XmlBlob getXhtml() {
if (xhtml == null) {
xhtml = new XmlBlob(); // init on demand
}
return xhtml;
}
/** Specifies the XHTML contents of this text construct. */
public void setXhtml(XmlBlob v) { xhtml = v; }
/**
* @return a plain-text representation of this text construct,
* or {@code null} in case of error
*/
@Override
public String getPlainText() {
try {
StringWriter sw = new StringWriter();
XmlWriter xw = new XmlWriter(sw);
xw.innerXml(xhtml.getBlob());
return HtmlToText.htmlToPlainText(sw.toString());
} catch (IOException e) {
// IOException isn't very meaningful to callers, so it's better to
// return null in this case.
return null;
}
}
/**
* Generates XML in the Atom format.
*
* @param w
* output writer
*
* @param elementName
* Atom element name
*
* @throws IOException
*/
@Override
public void generateAtom(XmlWriter w,
String elementName) throws IOException {
ArrayList<XmlWriter.Attribute> attrs =
new ArrayList<XmlWriter.Attribute>(2);
attrs.add(new XmlWriter.Attribute("type", "xhtml"));
if (lang != null) {
attrs.add(new XmlWriter.Attribute("xml:lang", lang));
}
XmlBlob.startElement(w, Namespaces.atomNs, elementName, xhtml, attrs, null);
XmlBlob.endElement(w, Namespaces.atomNs, elementName, xhtml);
}
/**
* Generates XML in the RSS format.
*
* @param w
* output writer
*
* @param elementName
* RSS element name
*
* @param rssFormat
* the restrictions on what HTML tags are allowed
*
* @throws IOException
*/
@Override
public void generateRss(XmlWriter w,
String elementName,
RssFormat rssFormat) throws IOException {
switch (rssFormat) {
case FULL_HTML:
// Because RSS doesn't allow child markup, we convert XHTML into an
// encoded string, just like HTML.
StringWriter sw = new StringWriter();
XmlWriter xw = new XmlWriter(sw);
xw.innerXml(xhtml.getBlob());
// At this point, sw contains the <xhtml:div> element.
w.simpleElement(Namespaces.rssNs, elementName, null, sw.toString());
break;
case PLAIN_TEXT:
w.simpleElement(Namespaces.rssNs, elementName, null, getPlainText());
break;
default:
assert false;
}
}
/** Parses XML in the Atom format. */
public class AtomHandler extends XmlParser.ElementHandler {
/**
* Class constructor.
*
* @throws IOException
*/
public AtomHandler() throws IOException {
xhtml = new XmlBlob();
initializeXmlBlob(xhtml, true, true);
lang = xmlLang;
}
/**
* Sets the language.
*
* @throws ParseException
*/
@Override
public void processAttribute(String namespace,
String localName,
String value)
throws ParseException {
if (namespace.equals(Namespaces.xml) && localName.equals("lang")) {
lang = xmlLang;
}
}
}
}