/*
* Copyright 1999-2004 The Apache Software Foundation.
*
* 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 org.apache.cocoon.components.language.markup.xsp;
import java.util.Collection;
import java.util.Iterator;
import org.apache.cocoon.xml.dom.DOMStreamer;
import org.apache.excalibur.xml.sax.XMLizable;
import org.w3c.dom.Node;
import org.xml.sax.ContentHandler;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.AttributesImpl;
/**
* Base class for XSP's object model manipulation logicsheets
*
* @author <a href="mailto:ricardo@apache.org">Ricardo Rocha</a>
* @author <a href="mailto:sylvain.wallez@anyware-tech.com">Sylvain Wallez</a>
* (Cocoon1 <code>xspExpr()</code> methods port)
* @version CVS $Id: XSPObjectHelper.java,v 1.1 2004/03/10 12:58:05 stephan Exp $
*/
public class XSPObjectHelper {
/**
* Empty attributes used for contentHandler.startElement()
*/
protected static final AttributesImpl emptyAttr = new AttributesImpl();
/**
* Output an element containing text only and no attributes
*
* @param contentHandler The SAX content handler
* @param name The element name
* @param data The data contained by the element
*/
protected static void elementData(
String uri,
String prefix,
ContentHandler contentHandler,
String name,
String data)
throws SAXException {
start(uri, prefix, contentHandler, name);
data(contentHandler, data);
end(uri, prefix, contentHandler, name);
}
/**
* Output an element containing text only and attributes
*
* @param contentHandler The SAX content handler
* @param name The element name
* @param data The data contained by the element
* @param attr The element attributes
*/
protected static void elementData(
String uri,
String prefix,
ContentHandler contentHandler,
String name,
String data,
AttributesImpl attr)
throws SAXException {
start(uri, prefix, contentHandler, name, attr);
data(contentHandler, data);
end(uri, prefix, contentHandler, name);
}
/**
* Start an element with the proper object's uri and prefix and no
* attributes
*
* @param contentHandler The SAX content handler
* @param name The element name
*/
protected static void start(
String uri,
String prefix,
ContentHandler contentHandler,
String name)
throws SAXException {
contentHandler.startElement(
uri,
name,
new StringBuffer(prefix).append(":").append(name).toString(),
emptyAttr);
}
/**
* Start an element with the proper object's uri and prefix and with
* attributes
*
* @param contentHandler The SAX content handler
* @param name The element name
* @param attr The element attributes
*/
protected static void start(
String uri,
String prefix,
ContentHandler contentHandler,
String name,
AttributesImpl attr)
throws SAXException {
contentHandler.startElement(
uri,
name,
new StringBuffer(prefix).append(":").append(name).toString(),
attr);
}
/**
* End an element with the proper object's uri and prefix
*
* @param contentHandler The SAX content handler
* @param name The element name
*/
protected static void end(
String uri,
String prefix,
ContentHandler contentHandler,
String name)
throws SAXException {
contentHandler.endElement(
uri,
name,
new StringBuffer(prefix).append(":").append(name).toString());
}
/**
* Add an attribute
*
* @param attr The attribute list
* @param name The attribute name
* @param value The attribute value
*/
protected static void addAttribute(
AttributesImpl attr,
String name,
String value)
throws SAXException {
attr.addAttribute("", name, name, "CDATA", value);
}
/**
* Add string data
*
* @param contentHandler The SAX content handler
* @param data The string data
*/
protected static void data(ContentHandler contentHandler, String data)
throws SAXException {
contentHandler.characters(data.toCharArray(), 0, data.length());
}
// <xsp:expr> methods
/**
* Implementation of <xsp:expr> for <code>char</code> :
* outputs characters representing the value.
*
* @param contentHandler the SAX content handler
* @param v the value
*/
public static void xspExpr(ContentHandler contentHandler, char v)
throws SAXException {
data(contentHandler, String.valueOf(v));
}
/**
* Implementation of <xsp:expr> for <code>byte</code> :
* outputs characters representing the value.
*
* @param contentHandler the SAX content handler
* @param v the value
*/
public static void xspExpr(ContentHandler contentHandler, byte v)
throws SAXException {
data(contentHandler, String.valueOf(v));
}
/**
* Implementation of <xsp:expr> for <code>boolean</code> :
* outputs characters representing the value (true / false).
*
* @param contentHandler the SAX content handler
* @param v the value
*/
public static void xspExpr(ContentHandler contentHandler, boolean v)
throws SAXException {
data(contentHandler, String.valueOf(v));
}
/**
* Implementation of <xsp:expr> for <code>int</code> :
* outputs characters representing the value.
*
* @param contentHandler the SAX content handler
* @param v the value
*/
public static void xspExpr(ContentHandler contentHandler, int v)
throws SAXException {
data(contentHandler, String.valueOf(v));
}
/**
* Implementation of <xsp:expr> for <code>long</code> :
* outputs characters representing the value.
*
* @param contentHandler the SAX content handler
* @param v the value
*/
public static void xspExpr(ContentHandler contentHandler, long v)
throws SAXException {
data(contentHandler, String.valueOf(v));
}
/**
* Implementation of <xsp:expr> for <code>long</code> :
* outputs characters representing the value.
*
* @param contentHandler the SAX content handler
* @param v the value
*/
public static void xspExpr(ContentHandler contentHandler, float v)
throws SAXException {
data(contentHandler, String.valueOf(v));
}
/**
* Implementation of <xsp:expr> for <code>double</code> :
* outputs characters representing the value.
*
* @param contentHandler the SAX content handler
* @param v the value
*/
public static void xspExpr(ContentHandler contentHandler, double v)
throws SAXException {
data(contentHandler, String.valueOf(v));
}
/**
* Implementation of <xsp:expr> for <code>String</code> :
* outputs characters representing the value.
*
* @param contentHandler the SAX content handler
* @param text the value
*/
public static void xspExpr(ContentHandler contentHandler, String text)
throws SAXException {
if (text != null) {
data(contentHandler, text);
}
}
// Now handled by XMLizable
// /**
// * Implementation of <xsp:expr> for <code>XMLFragment</code> :
// * outputs the value by calling <code>v.toSax(contentHandler)</code>.
// *
// * @param contentHandler the SAX content handler
// * @param v the XML fragment
// */
// public static void xspExpr(ContentHandler contentHandler, XMLFragment v) throws SAXException
// {
// if (v != null)
// {
// v.toSAX(contentHandler);
// }
// }
/**
* Implementation of <xsp:expr> for <code>XMLizable</code> :
* outputs the value by calling <code>v.toSax(contentHandler)</code>.
*
* @param contentHandler the SAX content handler
* @param v the XML fragment
*/
public static void xspExpr(ContentHandler contentHandler, XMLizable v)
throws SAXException {
if (v != null) {
v.toSAX(contentHandler);
}
}
/**
* Implementation of <xsp:expr> for <code>org.w3c.dom.Node</code> :
* converts the Node to a SAX event stream.
*
* @param contentHandler the SAX content handler
* @param v the value
*/
public static void xspExpr(ContentHandler contentHandler, Node v)
throws SAXException {
if (v != null) {
DOMStreamer streamer = new DOMStreamer(contentHandler);
streamer.stream(v);
}
}
/**
* Implementation of <xsp:expr> for <code>java.util.Collection</code> :
* outputs the value by calling <code>xspExpr()</code> on each element of the
* collection.
*
* @param contentHandler the SAX content handler
* @param v the XML fragment
*/
public static void xspExpr(ContentHandler contentHandler, Collection v)
throws SAXException {
if (v != null) {
Iterator iterator = v.iterator();
while (iterator.hasNext()) {
xspExpr(contentHandler, iterator.next());
}
}
}
/**
* Implementation of <xsp:expr> for <code>Object</code> depending on its class :
* <ul>
* <li>if it's an array, call <code>xspExpr()</code> on all its elements,</li>
* <li>if it's class has a specific <code>xspExpr()</code>implementation, use it,</li>
* <li>else, output it's string representation.</li>
* </ul>
*
* @param contentHandler the SAX content handler
* @param v the value
*/
public static void xspExpr(ContentHandler contentHandler, Object v)
throws SAXException {
if (v == null) {
return;
}
// Array: recurse over each element
if (v.getClass().isArray()) {
Object[] elements = (Object[]) v;
for (int i = 0; i < elements.length; i++) {
xspExpr(contentHandler, elements[i]);
}
return;
}
// Check handled object types in case they were not typed in the XSP
// XMLizable
if (v instanceof XMLizable) {
xspExpr(contentHandler, (XMLizable) v);
return;
}
// Now handled by XMLizable
// // XMLFragment
// if (v instanceof XMLFragment)
// {
// xspExpr(contentHandler, (XMLFragment)v);
// return;
// }
// Node
if (v instanceof Node) {
xspExpr(contentHandler, (Node) v);
return;
}
// Collection
if (v instanceof Collection) {
xspExpr(contentHandler, (Collection) v);
return;
}
// Give up: hope it's a string or has a meaningful string representation
data(contentHandler, String.valueOf(v));
}
}