/*
* 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.i18n;
import org.apache.avalon.framework.logger.AbstractLogEnabled;
import org.apache.excalibur.source.Source;
import org.apache.excalibur.source.SourceNotFoundException;
import org.apache.excalibur.source.SourceResolver;
import org.apache.excalibur.source.SourceValidity;
import org.apache.excalibur.source.impl.validity.ExpiresValidity;
import org.apache.cocoon.ResourceNotFoundException;
import org.apache.cocoon.components.source.SourceUtil;
import org.apache.cocoon.components.source.impl.validity.DelayedValidity;
import org.apache.cocoon.xml.ParamSaxBuffer;
import org.xml.sax.Attributes;
import org.xml.sax.ContentHandler;
import org.xml.sax.Locator;
import org.xml.sax.SAXException;
import java.net.MalformedURLException;
import java.util.Collections;
import java.util.HashMap;
import java.util.Locale;
import java.util.Map;
/**
* Implementation of <code>Bundle</code> interface for XML resources. Represents a
* single XML message bundle.
*
* <p>
* XML format for this resource bundle implementation is the following:
* <pre>
* <catalogue xml:lang="en">
* <message key="key1">Message <br/> Value 1</message>
* <message key="key2">Message <br/> Value 1</message>
* ...
* </catalogue>
* </pre>
*
* <p>
* Value can be any well formed XML snippet and it will be cached by the key specified
* in the attribute <code>key</code>. Objects returned by this {@link Bundle} implementation
* are instances of the {@link ParamSaxBuffer} class.
*
* <p>
* If value for a key is not present in this bundle, parent bundle will be queried.
*
* @author <a href="mailto:dev@cocoon.apache.org">Apache Cocoon Team</a>
* @version $Id: XMLResourceBundle.java 433543 2006-08-22 06:22:54Z crossley $
*/
public class XMLResourceBundle extends AbstractLogEnabled
implements Bundle {
/**
* XML bundle root element name
*/
public static final String EL_CATALOGUE = "catalogue";
/**
* XML bundle message element name
*/
public static final String EL_MESSAGE = "message";
/**
* XML bundle message element's key attribute name
*/
public static final String AT_KEY = "key";
/**
* Source URI of the bundle
*/
private String sourceURI;
/**
* Bundle validity
*/
private SourceValidity validity;
/**
* Locale of the bundle
*/
private Locale locale;
/**
* Parent of the current bundle
*/
protected Bundle parent;
/**
* Objects stored in the bundle
*/
protected Map values;
/**
* Processes XML bundle file and creates map of values
*/
private static class SAXContentHandler implements ContentHandler {
private Map values;
private int state;
private String namespace;
private ParamSaxBuffer buffer;
public SAXContentHandler(Map values) {
this.values = values;
}
public void setDocumentLocator(Locator arg0) {
// Ignore
}
public void startDocument() throws SAXException {
// Ignore
}
public void endDocument() throws SAXException {
// Ignore
}
public void processingInstruction(String arg0, String arg1) throws SAXException {
// Ignore
}
public void skippedEntity(String arg0) throws SAXException {
// Ignore
}
public void startElement(String ns, String localName, String qName, Attributes atts) throws SAXException {
switch (this.state) {
case 0:
// <i18n:catalogue>
if (!"".equals(ns) && !I18nUtils.matchesI18nNamespace(ns)) {
throw new SAXException("Root element <" + EL_CATALOGUE +
"> must be non-namespaced or in i18n namespace.");
}
if (!EL_CATALOGUE.equals(localName)) {
throw new SAXException("Root element must be <" + EL_CATALOGUE + ">.");
}
this.namespace = ns;
this.state++;
break;
case 1:
// <i18n:message>
if (!EL_MESSAGE.equals(localName)) {
throw new SAXException("<" + EL_CATALOGUE + "> must contain <" +
EL_MESSAGE + "> elements only.");
}
if (!this.namespace.equals(ns)) {
throw new SAXException("<" + EL_MESSAGE + "> element must be in '" +
this.namespace + "' namespace.");
}
String key = atts.getValue(AT_KEY);
if (key == null) {
throw new SAXException("<" + EL_MESSAGE + "> must have '" +
AT_KEY + "' attribute.");
}
this.buffer = new ParamSaxBuffer();
this.values.put(key, this.buffer);
this.state++;
break;
case 2:
this.buffer.startElement(ns, localName, qName, atts);
break;
default:
throw new SAXException("Internal error: Invalid state");
}
}
public void endElement(String ns, String localName, String qName) throws SAXException {
switch (this.state) {
case 0:
break;
case 1:
// </i18n:catalogue>
this.state--;
break;
case 2:
if (this.namespace.equals(ns) && EL_MESSAGE.equals(localName)) {
// </i18n:message>
this.buffer = null;
this.state--;
} else {
this.buffer.endElement(ns, localName, qName);
}
break;
default:
throw new SAXException("Internal error: Invalid state");
}
}
public void startPrefixMapping(String prefix, String uri) throws SAXException {
if (this.buffer != null) {
this.buffer.startPrefixMapping(prefix, uri);
}
}
public void endPrefixMapping(String prefix) throws SAXException {
if (this.buffer != null) {
this.buffer.endPrefixMapping(prefix);
}
}
public void ignorableWhitespace(char[] ch, int start, int length) throws SAXException {
if (this.buffer != null) {
this.buffer.ignorableWhitespace(ch, start, length);
}
}
public void characters(char[] ch, int start, int length) throws SAXException {
if (this.buffer != null) {
this.buffer.characters(ch, start, length);
}
}
}
/**
* Construct a bundle.
* @param sourceURI source URI of the XML bundle
* @param locale locale
* @param parent parent bundle of this bundle
*/
public XMLResourceBundle(String sourceURI, Locale locale, Bundle parent) {
this.sourceURI = sourceURI;
this.locale = locale;
this.parent = parent;
this.values = Collections.EMPTY_MAP;
}
/**
* (Re)Loads the XML bundle if necessary, based on the source URI.
* @return true if reloaded successfully
*/
protected boolean reload(SourceResolver resolver, long interval) {
Source newSource = null;
Map newValues;
try {
int valid = this.validity == null ? SourceValidity.INVALID : this.validity.isValid();
if (valid != SourceValidity.VALID) {
// Saved validity is not valid, get new source and validity
newSource = resolver.resolveURI(this.sourceURI);
SourceValidity newValidity = newSource.getValidity();
if (valid == SourceValidity.INVALID || this.validity.isValid(newValidity) != SourceValidity.VALID) {
newValues = new HashMap();
SourceUtil.toSAX(newSource, new SAXContentHandler(newValues));
synchronized (this) {
// Update source validity and values
if (interval > 0 && newValidity != null) {
this.validity = new DelayedValidity(interval, newValidity);
} else {
this.validity = newValidity;
}
this.values = newValues;
}
}
}
// Success
return true;
} catch (MalformedURLException e) {
getLogger().error("Bundle <" + this.sourceURI + "> not loaded: Invalid URI", e);
newValues = Collections.EMPTY_MAP;
} catch (ResourceNotFoundException e) {
// FIXME: this damn SourceUtil converts SNFE to RNFE!!!
if (getLogger().isInfoEnabled()) {
if (newSource != null && !newSource.exists()) {
// Nominal case where a bundle doesn't exist: log the message but not the exception
getLogger().info("Bundle <" + sourceURI + "> not loaded: Source URI not found");
} else {
// Log the exception
getLogger().info("Bundle <" + sourceURI + "> not loaded: Source URI not found", e);
}
}
newValues = Collections.EMPTY_MAP;
} catch (SourceNotFoundException e) {
if (getLogger().isInfoEnabled()) {
if (newSource != null && !newSource.exists()) {
// Nominal case where a bundle doesn't exist: log the message but not the exception
getLogger().info("Bundle <" + sourceURI + "> not loaded: Source URI not found");
} else {
// Log the exception
getLogger().info("Bundle <" + sourceURI + "> not loaded: Source URI not found", e);
}
}
newValues = Collections.EMPTY_MAP;
} catch (SAXException e) {
getLogger().error("Bundle <" + sourceURI + "> not loaded: Invalid XML", e);
// Keep existing loaded values
newValues = this.values;
} catch (Exception e) {
getLogger().error("Bundle <" + sourceURI + "> not loaded: Exception", e);
// Keep existing loaded values
newValues = this.values;
} finally {
if (newSource != null) {
resolver.release(newSource);
}
}
synchronized (this) {
// Use expires validity to delay next reloading.
if (interval > 0) {
this.validity = new ExpiresValidity(interval);
} else {
this.validity = null;
}
this.values = newValues;
}
// Failure
return false;
}
/**
* Gets the locale of the bundle.
*
* @return the locale
*/
public Locale getLocale() {
return this.locale;
}
/**
* Gets the source URI of the bundle.
*
* @return the source URI
*/
public String getSourceURI() {
return this.sourceURI;
}
/**
* Gets the validity of the bundle.
*
* @return the validity
*/
public SourceValidity getValidity() {
return this.validity;
}
/**
* Get an instance of the {@link ParamSaxBuffer} associated with the key.
*
* @param key the key
* @return the value, or null if no value associated with the key.
*/
public Object getObject(String key) {
if (key == null) {
return null;
}
Object value = this.values.get(key);
if (value != null) {
return value;
}
if (this.parent != null) {
return this.parent.getObject(key);
}
return null;
}
/**
* Get a string representation of the value object by key.
*
* @param key the key
* @return the string value, or null if no value associated with the key.
*/
public String getString(String key) {
if (key == null) {
return null;
}
Object value = this.values.get(key);
if (value != null) {
return value.toString();
}
if (this.parent != null) {
return this.parent.getString(key);
}
return null;
}
}