/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.forms.transformation;
import java.util.LinkedList;
import org.apache.cocoon.xml.AbstractXMLPipe;
import org.apache.cocoon.xml.SaxBuffer;
import org.xml.sax.Attributes;
import org.xml.sax.ContentHandler;
import org.xml.sax.Locator;
import org.xml.sax.SAXException;
import org.xml.sax.ext.LexicalHandler;
import org.xml.sax.helpers.LocatorImpl;
/**
* Base class for XMLPipe's. Allows the structure of the source code of
* the XMLPipe to match the structure of the data being transformed.
*
* @version $Id$
*/
public class EffectPipe extends AbstractXMLPipe {
/**
* Java 1.3 contentHandler access method.
* <br>
* Access to {#contentHandler} from inner class on Java 1.3 causes NoSuchMethod error.
*/
private ContentHandler getContentHandler() {
return super.contentHandler;
}
/**
* Java 1.3 lexicalHandler access method.
* <br>
* Access to {#lexicalHandler} from inner class on Java 1.3 causes NoSuchMethod error.
*/
private LexicalHandler getLexicalHandler() {
return super.lexicalHandler;
}
/**
* Handler interface. Accepts SAX events, can return other handler
* to replace self for further events.
*/
protected interface Handler {
public Handler startDocument()
throws SAXException;
public void endDocument()
throws SAXException;
public void startPrefixMapping(String prefix, String uri)
throws SAXException;
public void endPrefixMapping(String prefix)
throws SAXException;
public Handler startElement(String uri, String loc, String raw, Attributes attrs)
throws SAXException;
/**
* Called before startElement, handler can decide what other handler should process
* next startElement.
*/
public Handler nestedElement(String uri, String loc, String raw, Attributes attrs)
throws SAXException;
public void endElement(String uri, String loc, String raw)
throws SAXException;
public Handler characters(char ch[], int start, int length)
throws SAXException;
public Handler ignorableWhitespace(char ch[], int start, int length)
throws SAXException;
public Handler processingInstruction(String target, String data)
throws SAXException;
public Handler skippedEntity(String name)
throws SAXException;
public Handler startDTD(String name, String publicId, String systemId)
throws SAXException;
public Handler endDTD()
throws SAXException;
public Handler startEntity(String name)
throws SAXException;
public Handler endEntity(String name)
throws SAXException;
public Handler startCDATA()
throws SAXException;
public Handler endCDATA()
throws SAXException;
public Handler comment(char c[], int start, int len)
throws SAXException;
}
/**
* Ignores all events
*/
protected class NullHandler implements Handler {
public Handler startDocument() throws SAXException {
return this;
}
public void endDocument() throws SAXException {
}
public void startPrefixMapping(String prefix, String uri) throws SAXException {
}
public void endPrefixMapping(String prefix) throws SAXException {
}
public Handler nestedElement(String uri, String loc, String raw, Attributes attrs) throws SAXException {
return this;
}
public Handler startElement(String uri, String loc, String raw, Attributes attrs) throws SAXException {
return this;
}
public void endElement(String uri, String loc, String raw) throws SAXException {
}
public Handler characters(char ch[], int start, int length) throws SAXException {
return this;
}
public Handler ignorableWhitespace(char ch[], int start, int length) throws SAXException {
return this;
}
public Handler processingInstruction(String target, String data) throws SAXException {
return this;
}
public Handler skippedEntity(String name) throws SAXException {
return this;
}
public Handler startDTD(String name, String publicId, String systemId) throws SAXException {
return this;
}
public Handler endDTD() throws SAXException {
return this;
}
public Handler startEntity(String name) throws SAXException {
return this;
}
public Handler endEntity(String name) throws SAXException {
return this;
}
public Handler startCDATA() throws SAXException {
return this;
}
public Handler endCDATA() throws SAXException {
return this;
}
public Handler comment(char c[], int start, int len) throws SAXException {
return this;
}
}
/**
* Buffers content into the pipe's SAX buffer.
*/
protected class BufferHandler extends NullHandler {
public Handler startDocument() throws SAXException {
if (buffer != null) buffer.startDocument();
return this;
}
public void setDocumentLocator(Locator paramLocator) {
locator = new LocatorImpl(paramLocator);
if (buffer != null) buffer.setDocumentLocator(paramLocator);
}
public void endDocument() throws SAXException {
if (buffer != null) buffer.endDocument();
}
public void startPrefixMapping(String prefix, String uri) throws SAXException {
if (buffer != null) buffer.startPrefixMapping(prefix, uri);
}
public void endPrefixMapping(String prefix) throws SAXException {
if (buffer != null) buffer.endPrefixMapping(prefix);
}
public Handler startElement(String uri, String loc, String raw, Attributes attrs) throws SAXException {
if (buffer != null) buffer.startElement(uri, loc, raw, attrs);
return this;
}
public void endElement(String uri, String loc, String raw) throws SAXException {
if (buffer != null) buffer.endElement(uri, loc, raw);
}
public Handler characters(char ch[], int start, int length) throws SAXException {
if (buffer != null) buffer.characters(ch, start, length);
return this;
}
public Handler ignorableWhitespace(char ch[], int start, int length) throws SAXException {
if (buffer != null) buffer.ignorableWhitespace(ch, start, length);
return this;
}
public Handler processingInstruction(String target, String data) throws SAXException {
if (buffer != null) buffer.processingInstruction(target, data);
return this;
}
public Handler skippedEntity(String name) throws SAXException {
if (buffer != null) buffer.skippedEntity(name);
return this;
}
public Handler startDTD(String name, String publicId, String systemId) throws SAXException {
if (buffer != null) buffer.startDTD(name, publicId, systemId);
return this;
}
public Handler endDTD() throws SAXException {
if (buffer != null) buffer.endDTD();
return this;
}
public Handler startEntity(String name) throws SAXException {
if (buffer != null) buffer.startEntity(name);
return this;
}
public Handler endEntity(String name) throws SAXException {
if (buffer != null) buffer.endEntity(name);
return this;
}
public Handler startCDATA() throws SAXException {
if (buffer != null) buffer.startCDATA();
return this;
}
public Handler endCDATA() throws SAXException {
if (buffer != null) buffer.endCDATA();
return this;
}
public Handler comment(char c[], int start, int len) throws SAXException {
if (buffer != null) buffer.comment(c, start, len);
return this;
}
}
/**
* Copies events over into the contentHandler
*/
protected class CopyHandler extends NullHandler {
public Handler startDocument() throws SAXException {
getContentHandler().startDocument();
return this;
}
public void endDocument() throws SAXException {
getContentHandler().endDocument();
}
public void startPrefixMapping(String prefix, String uri) throws SAXException {
getContentHandler().startPrefixMapping(prefix, uri);
}
public void endPrefixMapping(String prefix) throws SAXException {
getContentHandler().endPrefixMapping(prefix);
}
public Handler startElement(String uri, String loc, String raw, Attributes attrs) throws SAXException {
getContentHandler().startElement(uri, loc, raw, attrs);
return this;
}
public void endElement(String uri, String loc, String raw) throws SAXException {
getContentHandler().endElement(uri, loc, raw);
}
public Handler characters(char ch[], int start, int length) throws SAXException {
getContentHandler().characters(ch, start, length);
return this;
}
public Handler ignorableWhitespace(char ch[], int start, int length) throws SAXException {
getContentHandler().ignorableWhitespace(ch, start, length);
return this;
}
public Handler processingInstruction(String target, String data) throws SAXException {
getContentHandler().processingInstruction(target, data);
return this;
}
public Handler skippedEntity(String name) throws SAXException {
getContentHandler().skippedEntity(name);
return this;
}
public Handler startDTD(String name, String publicId, String systemId) throws SAXException {
if (getLexicalHandler() != null) getLexicalHandler().startDTD(name, publicId, systemId);
return this;
}
public Handler endDTD() throws SAXException {
if (getLexicalHandler() != null) getLexicalHandler().endDTD();
return this;
}
public Handler startEntity(String name) throws SAXException {
if (getLexicalHandler() != null) getLexicalHandler().startEntity(name);
return this;
}
public Handler endEntity(String name) throws SAXException {
if (getLexicalHandler() != null) getLexicalHandler().endEntity(name);
return this;
}
public Handler startCDATA() throws SAXException {
if (getLexicalHandler() != null) getLexicalHandler().startCDATA();
return this;
}
public Handler endCDATA() throws SAXException {
if (getLexicalHandler() != null) getLexicalHandler().endCDATA();
return this;
}
public Handler comment(char c[], int start, int len) throws SAXException {
if (getLexicalHandler() != null) getLexicalHandler().comment(c, start, len);
return this;
}
}
/**
* Throws exception on most events, with the exception of ignorableWhitespace.
*/
protected class ErrorHandler extends NullHandler {
protected String getName() {
return "<unknown>";
}
public Handler startDocument() throws SAXException {
throw new SAXException("Unexpected startDocument in '" + getName() + "' (" + getLocation() + ")");
}
public void endDocument() throws SAXException {
throw new SAXException("Unexpected endDocument in '" + getName() + "' (" + getLocation() + ")");
}
public void startPrefixMapping(String prefix, String uri) throws SAXException {
throw new SAXException("Unexpected startPrefixMapping in '" + getName() + "' (" + getLocation() + ")");
}
public void endPrefixMapping(String prefix) throws SAXException {
throw new SAXException("Unexpected endPrefixMapping in '" + getName() + "' (" + getLocation() + ")");
}
public Handler startElement(String uri, String loc, String raw, Attributes attrs) throws SAXException {
throw new SAXException("Unexpected startElement in '" + getName() + "' (" + getLocation() + ")");
}
public void endElement(String uri, String loc, String raw) throws SAXException {
throw new SAXException("Unexpected endElement in '" + getName() + "' (" + getLocation() + ")");
}
public Handler characters(char ch[], int start, int length) throws SAXException {
throw new SAXException("Unexpected characters in '" + getName() + "' (" + getLocation() + ")");
}
public Handler processingInstruction(String target, String data) throws SAXException {
throw new SAXException("Unexpected processingInstruction in '" + getName() + "' (" + getLocation() + ")");
}
public Handler skippedEntity(String name) throws SAXException {
throw new SAXException("Unexpected skippedEntity in '" + getName() + "' (" + getLocation() + ")");
}
public Handler startDTD(String name, String publicId, String systemId) throws SAXException {
throw new SAXException("Unexpected startDTD in '" + getName() + "' (" + getLocation() + ")");
}
public Handler endDTD() throws SAXException {
throw new SAXException("Unexpected endDTD in '" + getName() + "' (" + getLocation() + ")");
}
public Handler startEntity(String name) throws SAXException {
throw new SAXException("Unexpected startEntity in '" + getName() + "' (" + getLocation() + ")");
}
public Handler endEntity(String name) throws SAXException {
throw new SAXException("Unexpected endEntity in '" + getName() + "' (" + getLocation() + ")");
}
public Handler startCDATA() throws SAXException {
throw new SAXException("Unexpected startCDATA in '" + getName() + "' (" + getLocation() + ")");
}
public Handler endCDATA() throws SAXException {
throw new SAXException("Unexpected endCDATA in '" + getName() + "' (" + getLocation() + ")");
}
public Handler comment(char c[], int start, int len) throws SAXException {
throw new SAXException("Unexpected comment in '" + getName() + "' (" + getLocation() + ")");
}
}
protected final Handler hNull = new NullHandler();
protected final Handler hBuffer = new BufferHandler();
protected Locator locator;
private LinkedList handlers;
private Handler handler;
private LinkedList buffers;
private LinkedList locators;
protected SaxBuffer buffer;
/**
* Initialize the pipe before starting processing
*/
protected void init(Handler top) {
locators = new LinkedList();
handlers = new LinkedList();
handler = top;
}
/**
* Recycle the pipe after processing
*/
public void recycle() {
super.recycle();
handlers = null;
handler = null;
buffers = null;
buffer = null;
locator = null;
locators = null;
}
/**
* @return current location (if known)
*/
protected String getLocation() {
if (locator == null) {
return "unknown";
}
return " (" + locator.getSystemId() + ":" +
locator.getLineNumber() + ":" +
locator.getColumnNumber() + ")";
}
protected void pushHandler(Handler handler) {
this.handlers.addFirst(this.handler);
this.handler = handler;
}
protected void popHandler() {
this.handler = (Handler) this.handlers.removeFirst();
}
protected void beginBuffer() {
if (this.buffer != null) {
if (this.buffers == null) {
this.buffers = new LinkedList();
}
this.buffers.addFirst(this.buffer);
}
if (locator != null) {
locators.addFirst(locator);
locator = new LocatorImpl(locator);
}
this.buffer = new SaxBuffer();
}
protected SaxBuffer endBuffer() {
SaxBuffer buffer = this.buffer;
if (this.buffers != null && this.buffers.size() > 0) {
this.buffer = (SaxBuffer) this.buffers.removeFirst();
} else {
this.buffer = null;
}
if (locator != null) {
locator = (Locator)locators.removeFirst();
}
return buffer;
}
//
// ContentHandler methods
//
public void setDocumentLocator(Locator locator) {
this.locator = locator;
}
public void startDocument() throws SAXException {
pushHandler(handler.startDocument());
}
public void endDocument() throws SAXException {
handler.endDocument();
popHandler();
}
public void startPrefixMapping(String prefix, String uri) throws SAXException {
handler.startPrefixMapping(prefix, uri);
}
public void endPrefixMapping(String prefix) throws SAXException {
handler.endPrefixMapping(prefix);
}
public void startElement(String uri, String loc, String raw, Attributes attrs) throws SAXException {
pushHandler(handler.nestedElement(uri, loc, raw, attrs));
handler = handler.startElement(uri, loc, raw, attrs);
}
public void endElement(String uri, String loc, String raw) throws SAXException {
handler.endElement(uri, loc, raw);
popHandler();
}
public void characters(char ch[], int start, int len) throws SAXException {
handler = handler.characters(ch, start, len);
}
public void ignorableWhitespace(char ch[], int start, int len) throws SAXException {
handler = handler.ignorableWhitespace(ch, start, len);
}
public void processingInstruction(String target, String data) throws SAXException {
handler = handler.processingInstruction(target, data);
}
public void skippedEntity(String name) throws SAXException {
handler = handler.skippedEntity(name);
}
//
// LexicalHandler methods
//
public void startDTD(String name, String publicId, String systemId) throws SAXException {
handler = handler.startDTD(name, publicId, systemId);
}
public void endDTD() throws SAXException {
handler = handler.endDTD();
}
public void startEntity(String name) throws SAXException {
handler = handler.startEntity(name);
}
public void endEntity(String name) throws SAXException {
handler = handler.endEntity(name);
}
public void startCDATA() throws SAXException {
handler = handler.startCDATA();
}
public void endCDATA() throws SAXException {
handler = handler.endCDATA();
}
public void comment(char ch[], int start, int len) throws SAXException {
handler = handler.comment(ch, start, len);
}
}