/*
* 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.transformation.pagination;
import org.apache.avalon.framework.activity.Disposable;
import org.apache.avalon.framework.parameters.Parameters;
import org.apache.avalon.framework.service.ServiceException;
import org.apache.avalon.framework.service.ServiceManager;
import org.apache.avalon.framework.service.Serviceable;
import org.apache.cocoon.ProcessingException;
import org.apache.cocoon.caching.CacheableProcessingComponent;
import org.apache.cocoon.environment.ObjectModelHelper;
import org.apache.cocoon.environment.Request;
import org.apache.cocoon.environment.SourceResolver;
import org.apache.cocoon.transformation.AbstractTransformer;
import org.apache.excalibur.source.Source;
import org.apache.excalibur.source.SourceException;
import org.apache.excalibur.source.SourceValidity;
import org.apache.excalibur.source.impl.validity.AggregatedValidity;
import org.apache.excalibur.source.impl.validity.TimeStampValidity;
import org.apache.excalibur.store.Store;
import org.apache.excalibur.xml.sax.SAXParser;
import org.xml.sax.Attributes;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.AttributesImpl;
import java.io.IOException;
import java.io.Serializable;
import java.util.Map;
/**
* A paginating transformer.
*
* @author <a href="mailto:stefano@apache.org">Stefano Mazzocchi</a>
* @author <a href="mailto:stephan@apache.org">Stephan Michels</a>
* @author <a href="mailto:bhtek@yahoo.com">Boon Hian Tek</a>
* @version CVS $Id: Paginator.java,v 1.6 2004/05/17 16:17:11 vgritsenko Exp $
*/
public class Paginator extends AbstractTransformer
implements Serviceable, Disposable, CacheableProcessingComponent {
public static final String PAGINATE_URI = "http://apache.org/cocoon/paginate/1.0";
public static final String PAGINATE_PREFIX = "page";
public static final String PAGINATE_PREFIX_TOKEN = PAGINATE_PREFIX + ":";
private ServiceManager manager;
private SAXParser parser;
private Store store;
private SourceResolver resolver;
private Source inputSource;
private int page;
private int item;
private String itemGroup;
private String requestURI;
private Request request;
private Pagesheet pagesheet;
private int level;
private boolean prefixMapping;
/**
* Set the current <code>ServiceManager</code> instance used by this
* <code>Serviceable</code>.
*
* @param manager Description of the Parameter
*/
public void service(ServiceManager manager) throws ServiceException {
try {
this.manager = manager;
getLogger().debug("Looking up "+SAXParser.ROLE);
this.parser = (SAXParser) manager.lookup(SAXParser.ROLE);
getLogger().debug("Looking up " + Store.TRANSIENT_STORE);
this.store = (Store) manager.lookup(Store.TRANSIENT_STORE);
} catch (Exception e) {
getLogger().error("Could not find component", e);
}
}
/**
* Dispose this component.
*/
public void dispose() {
if (this.parser!=null) {
this.manager.release(this.parser);
} else {
this.parser = null;
}
if (this.store!=null) {
this.manager.release(this.store);
} else {
this.store = null;
}
}
/**
* Setup the transformer.
*/
public void setup(SourceResolver resolver, Map objectModel, String src,
Parameters par)
throws ProcessingException, SAXException,
IOException {
if (src == null) {
throw new ProcessingException("I need the paginate instructions (pagesheet) to continue. Set the 'src' attribute.");
}
try {
this.level = 0;
this.prefixMapping = false;
this.resolver = resolver;
this.inputSource = resolver.resolveURI(src);
if (getLogger().isDebugEnabled()) {
getLogger().debug("Using pagesheet: '"+
this.inputSource.getURI()+"' in "+this+
", last modified: "+
this.inputSource.getLastModified());
}
this.page = par.getParameterAsInteger("page", 1);
this.item = par.getParameterAsInteger("item", 0);
this.itemGroup = par.getParameter("item-group", "");
if (getLogger().isDebugEnabled()) {
getLogger().debug("Paginating with [page = "+this.page+
", item = "+this.item+", item-group = "+
this.itemGroup+"]");
}
this.request = ObjectModelHelper.getRequest(objectModel);
this.requestURI = request.getRequestURI();
// Get the pagesheet factory from the Store if available,
// otherwise load it and put it into the store for further request
if (store!=null) {
pagesheet = (Pagesheet) store.get(src);
}
// If not in the store or if pagesheet has changed, loads and stores it
if ((pagesheet==null) ||
pagesheet.modifiedSince(inputSource.getLastModified())) {
pagesheet = new Pagesheet();
pagesheet.setLastModified(inputSource.getLastModified());
parser.parse(new InputSource(inputSource.getInputStream()),
pagesheet);
if (store!=null) {
store.store(src, pagesheet);
}
}
// Clone it in order to avoid concurrency collisions since the
// implementation is not reentrant.
this.pagesheet = (Pagesheet) this.pagesheet.clone();
} catch (SourceException se) {
throw new ProcessingException("Could not retrieve source '" +
src + "'", se);
}
}
public void recycle() {
if (null != this.inputSource) {
this.resolver.release(this.inputSource);
this.inputSource = null;
}
this.resolver = null;
super.recycle();
}
/**
* Generate the unique key. This key must be unique inside the space of
* this component. This method must be invoked before the
* generateValidity() method.
*
* @return The generated key or <code>null</code> if the component is
* currently not cacheable.
*/
public Serializable getKey() {
if (this.inputSource.getLastModified()!=0) {
return this.inputSource.getURI()+page;
} else {
return null;
}
}
/**
* Generate the validity object. Before this method can be invoked the
* generateKey() method must be invoked.
*
* @return The generated validity object or <code>null</code> if the
* component is currently not cacheable.
*/
public SourceValidity getValidity() {
if (this.inputSource.getLastModified()!=0) {
AggregatedValidity validity = new AggregatedValidity();
validity.add(new TimeStampValidity(page));
validity.add(this.inputSource.getValidity());
return validity;
} else {
return null;
}
}
/**
* Receive notification of the beginning of an element.
*
* @param uri The Namespace URI, or the empty string if the
* element has no Namespace URI or if Namespace processing is not being
* performed.
* @param loc The local name (without prefix), or the empty
* string if Namespace processing is not being performed.
* @param raw The raw XML 1.0 name (with prefix), or the empty
* string if raw names are not available.
* @param a The attributes attached to the element. If there
* are no attributes, it shall be an empty Attributes object.
*/
public void startElement(String uri, String loc, String raw,
Attributes a) throws SAXException {
if ( !prefixMapping) {
super.startPrefixMapping(PAGINATE_PREFIX, PAGINATE_URI);
this.prefixMapping = true;
}
level++;
pagesheet.processStartElement(uri, loc);
if (pagesheet.isInPage(page, item, itemGroup)) {
int itemCount = pagesheet.itemCount(uri, loc);
if (itemCount>0) {
String itemGroup = pagesheet.getItemGroupName(uri, loc);
AttributesImpl atts = new AttributesImpl(a);
atts.addAttribute(PAGINATE_URI, "item",
PAGINATE_PREFIX_TOKEN+"item", "CDATA",
String.valueOf(itemCount));
atts.addAttribute(PAGINATE_URI, "item-group",
PAGINATE_PREFIX_TOKEN+"item-group",
"CDATA", itemGroup);
super.startElement(uri, loc, raw, atts);
} else {
super.startElement(uri, loc, raw, a);
}
}
}
/**
* Receive notification of the end of an element.
*
* @param uri The Namespace URI, or the empty string if the
* element has no Namespace URI or if Namespace processing is not being
* performed.
* @param loc The local name (without prefix), or the empty
* string if Namespace processing is not being performed.
* @param raw The raw XML 1.0 name (with prefix), or the empty
* string if raw names are not available.
*/
public void endElement(String uri, String loc,
String raw) throws SAXException {
level--;
// Prevent infinite recursive loop.
if (PAGINATE_URI.equals(uri)) {
super.endElement(uri, loc, raw);
return;
}
if (pagesheet.isInPage(page, item, itemGroup)) {
if (level==0) {
if (item==0) {
int totalPages = pagesheet.getTotalPages();
PageRules rules = pagesheet.getPageRules(page);
Integer[] rangeLinks = rules.getRangeLinks();
int unitLinks = rules.unitLinks;
int currentPage = page;
// call add paginate
addPaginateTags(rangeLinks, unitLinks, currentPage,
totalPages, requestURI, this);
} else {
int totalItems = pagesheet.getTotalItems(itemGroup);
AttributesImpl atts = new AttributesImpl();
atts.addAttribute("", "current", "current", "CDATA",
String.valueOf(item));
atts.addAttribute("", "total", "total", "CDATA",
String.valueOf(totalItems));
atts.addAttribute("", "current-uri", "current-uri",
"CDATA", requestURI);
atts.addAttribute("", "clean-uri", "clean-uri",
"CDATA", cleanURI(requestURI, item));
atts.addAttribute("", "page", "page", "CDATA",
String.valueOf(pagesheet.getPageForItem(item,
itemGroup)));
super.startElement(PAGINATE_URI, "item",
PAGINATE_PREFIX_TOKEN+"item", atts);
if (item>1) {
atts.clear();
atts.addAttribute("", "type", "type", "CDATA",
"prev");
atts.addAttribute("", "uri", "uri", "CDATA",
encodeURI(requestURI, item,
item-1));
super.startElement(PAGINATE_URI, "link",
PAGINATE_PREFIX_TOKEN+"link",
atts);
super.endElement(PAGINATE_URI, "link",
PAGINATE_PREFIX_TOKEN+"link");
}
if (item<=totalItems) {
atts.clear();
atts.addAttribute("", "type", "type", "CDATA",
"next");
atts.addAttribute("", "uri", "uri", "CDATA",
encodeURI(requestURI, item,
item+1));
super.startElement(PAGINATE_URI, "link",
PAGINATE_PREFIX_TOKEN+"link",
atts);
super.endElement(PAGINATE_URI, "link",
PAGINATE_PREFIX_TOKEN+"link");
}
super.endElement(PAGINATE_URI, "item",
PAGINATE_PREFIX_TOKEN+"item");
}
super.endPrefixMapping(PAGINATE_PREFIX);
}
super.endElement(uri, loc, raw);
}
pagesheet.processEndElement(uri, loc);
}
public static void addPaginateTags(Integer[] rangeLinks, int unitLinks,
int currentPage, int totalPages,
String requestURI,
AbstractTransformer saxTransformer)
throws SAXException {
AttributesImpl atts = new AttributesImpl();
atts.addAttribute("", "current", "current", "CDATA",
String.valueOf(currentPage));
atts.addAttribute("", "total", "total", "CDATA",
String.valueOf(totalPages));
atts.addAttribute("", "current-uri", "current-uri", "CDATA",
requestURI);
atts.addAttribute("", "clean-uri", "clean-uri", "CDATA",
Paginator.cleanURI(requestURI, currentPage));
saxTransformer.startElement(Paginator.PAGINATE_URI, "page",
Paginator.PAGINATE_PREFIX_TOKEN+"page",
atts);
for (int i = rangeLinks.length-1; i>-1; i--) {
int rangeLink = rangeLinks[i].intValue();
if ((rangeLink>0) && (currentPage-rangeLink>=1)) {
atts.clear();
atts.addAttribute("", "type", "type", "CDATA", "prev");
atts.addAttribute("", "range", "range", "CDATA",
rangeLinks[i].toString());
atts.addAttribute("", "uri", "uri", "CDATA",
Paginator.encodeURI(requestURI,
currentPage,
currentPage-rangeLink));
atts.addAttribute("", "page", "page", "CDATA",
String.valueOf(currentPage-rangeLink));
saxTransformer.startElement(Paginator.PAGINATE_URI,
"range-link",
Paginator.PAGINATE_PREFIX_TOKEN+
"range-link", atts);
saxTransformer.endElement(Paginator.PAGINATE_URI,
"range-link",
Paginator.PAGINATE_PREFIX_TOKEN+
"range-link");
}
}
for (int i = currentPage-unitLinks; i<currentPage; i++) {
if (i>0) {
atts.clear();
atts.addAttribute("", "type", "type", "CDATA", "prev");
atts.addAttribute("", "uri", "uri", "CDATA",
Paginator.encodeURI(requestURI,
currentPage, i));
atts.addAttribute("", "page", "page", "CDATA",
String.valueOf(i));
saxTransformer.startElement(Paginator.PAGINATE_URI, "link",
Paginator.PAGINATE_PREFIX_TOKEN+
"link", atts);
saxTransformer.endElement(Paginator.PAGINATE_URI, "link",
Paginator.PAGINATE_PREFIX_TOKEN+
"link");
}
}
for (int i = currentPage+1; i<=currentPage+unitLinks; i++) {
if (i<=totalPages) {
atts.clear();
atts.addAttribute("", "type", "type", "CDATA", "next");
atts.addAttribute("", "uri", "uri", "CDATA",
Paginator.encodeURI(requestURI,
currentPage, i));
atts.addAttribute("", "page", "page", "CDATA",
String.valueOf(i));
saxTransformer.startElement(Paginator.PAGINATE_URI, "link",
Paginator.PAGINATE_PREFIX_TOKEN+
"link", atts);
saxTransformer.endElement(Paginator.PAGINATE_URI, "link",
Paginator.PAGINATE_PREFIX_TOKEN+
"link");
}
}
for (int i = 0; i<rangeLinks.length; i++) {
int rangeLink = rangeLinks[i].intValue();
if ((rangeLink>0) && (currentPage+rangeLink<=totalPages)) {
atts.clear();
atts.addAttribute("", "type", "type", "CDATA", "next");
atts.addAttribute("", "range", "range", "CDATA",
rangeLinks[i].toString());
atts.addAttribute("", "uri", "uri", "CDATA",
Paginator.encodeURI(requestURI,
currentPage,
currentPage+rangeLink));
atts.addAttribute("", "page", "page", "CDATA",
String.valueOf(currentPage+rangeLink));
saxTransformer.startElement(Paginator.PAGINATE_URI,
"range-link",
Paginator.PAGINATE_PREFIX_TOKEN+
"range-link", atts);
saxTransformer.endElement(Paginator.PAGINATE_URI,
"range-link",
Paginator.PAGINATE_PREFIX_TOKEN+
"range-link");
}
}
saxTransformer.endElement(Paginator.PAGINATE_URI, "page",
Paginator.PAGINATE_PREFIX_TOKEN+"page");
}
/**
* Receive notification of character data.
*
* @param c The characters from the XML document.
* @param start The start position in the array.
* @param len The number of characters to read from the array.
*/
public void characters(char c[], int start, int len) throws SAXException {
pagesheet.processCharacters(c, start, len);
if (pagesheet.isInPage(page, item, itemGroup)) {
super.characters(c, start, len);
}
}
/**
* Receive notification of ignorable whitespace in element content.
*
* @param c The characters from the XML document.
* @param start The start position in the array.
* @param len The number of characters to read from the array.
*/
public void ignorableWhitespace(char c[], int start,
int len) throws SAXException {
if (pagesheet.isInPage(page, item, itemGroup)) {
super.ignorableWhitespace(c, start, len);
}
}
/**
* Receive notification of a processing instruction.
*
* @param target The processing instruction target.
* @param data The processing instruction data, or null if none
* was supplied.
*/
public void processingInstruction(String target,
String data) throws SAXException {
if (pagesheet.isInPage(page, item, itemGroup)) {
super.processingInstruction(target, data);
}
}
/**
* Receive notification of a skipped entity.
*
* @param name The name of the skipped entity. If it is a
* parameter entity, the name will begin with '%'.
*/
public void skippedEntity(String name) throws SAXException {
if (pagesheet.isInPage(page, item, itemGroup)) {
super.skippedEntity(name);
}
}
/**
* Report the start of DTD declarations, if any.
*
* @param name The document type name.
* @param publicId The declared public identifier for the external
* DTD subset, or null if none was declared.
* @param systemId The declared system identifier for the external
* DTD subset, or null if none was declared.
*/
public void startDTD(String name, String publicId,
String systemId) throws SAXException {
if (pagesheet.isInPage(page, item, itemGroup)) {
super.startDTD(name, publicId, systemId);
} else {
throw new SAXException("Recieved startDTD not in page.");
}
}
/**
* Report the end of DTD declarations.
*/
public void endDTD() throws SAXException {
if (pagesheet.isInPage(page, item, itemGroup)) {
super.endDTD();
} else {
throw new SAXException("Recieved endDTD not in page.");
}
}
/**
* Report the beginning of an entity.
*
*@param name The name of the entity. If it is a parameter
* entity, the name will begin with '%'.
*/
public void startEntity(String name) throws SAXException {
if (pagesheet.isInPage(page, item, itemGroup)) {
super.startEntity(name);
}
}
/**
* Report the end of an entity.
*
* @param name The name of the entity that is ending.
*/
public void endEntity(String name) throws SAXException {
if (pagesheet.isInPage(page, item, itemGroup)) {
super.endEntity(name);
}
}
/**
* Report the start of a CDATA section.
*/
public void startCDATA() throws SAXException {
if (pagesheet.isInPage(page, item, itemGroup)) {
super.startCDATA();
}
}
/**
* Report the end of a CDATA section.
*/
public void endCDATA() throws SAXException {
if (pagesheet.isInPage(page, item, itemGroup)) {
super.endCDATA();
}
}
/**
* Report an XML comment anywhere in the document.
*
* @param ch An array holding the characters in the comment.
* @param start The starting position in the array.
* @param len The number of characters to use from the array.
*/
public void comment(char ch[], int start, int len) throws SAXException {
if (pagesheet.isInPage(page, item, itemGroup)) {
super.comment(ch, start, len);
}
}
/**
* Removes the pagination encoding from the URI by removing the page number
* and the previous and next character.
*/
public static String cleanURI(String uri, int current) {
String currentS = String.valueOf(current);
int index = uri.lastIndexOf(currentS);
if (index==-1) {
return uri;
} else {
return uri.substring(0, index-1)+
uri.substring(index+currentS.length()+1);
}
}
/**
* Encode the next page in the given URI. First tries to use the existing
* encoding by replacing the current page number, but if the current
* encoding is not found it appends "(xx)" to the filename (before the file
* extention, if any) where "xx" is the next page value.
*/
public static String encodeURI(String uri, int current, int next) {
String currentS = String.valueOf(current);
String nextS = String.valueOf(next);
int index = uri.lastIndexOf(currentS);
if (index==-1) {
index = uri.lastIndexOf('.');
if (index==-1) {
return uri+"("+nextS+")";
} else {
return uri.substring(0, index)+"("+nextS+")."+
uri.substring(index+1);
}
} else {
return uri.substring(0, index)+nextS+
uri.substring(index+currentS.length());
}
}
}