/*
* 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.components.serializers;
import java.io.IOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.UnsupportedEncodingException;
import java.util.Arrays;
import org.apache.avalon.excalibur.pool.Recyclable;
import org.apache.avalon.framework.configuration.Configurable;
import org.apache.avalon.framework.configuration.Configuration;
import org.apache.avalon.framework.configuration.ConfigurationException;
import org.apache.cocoon.components.serializers.encoding.XMLEncoder;
import org.apache.cocoon.components.serializers.encoding.Charset;
import org.apache.cocoon.components.serializers.encoding.CharsetFactory;
import org.apache.cocoon.components.serializers.encoding.Encoder;
import org.apache.cocoon.components.serializers.util.Namespaces;
import org.apache.cocoon.serialization.Serializer;
import org.apache.commons.lang.SystemUtils;
import org.xml.sax.Attributes;
import org.xml.sax.Locator;
import org.xml.sax.SAXException;
/**
* <p>An abstract serializer supporting multiple encodings.</p>
*
* <p>This serializer can accept the following configuration whenever it
* is declared into a sitemap:</p>
*
* <pre>
* <serializer class="org.apache.cocoon.components.serializers..." ... >
* <encoding>myencoding</encoding>
* <indent>myindenting</indent>
* <setContentLength>false</setContentLength>
* </serializer>
* </pre>
*
* <p>The value indicated by <i>myencoding</i> must be replaced with a valid
* charset encoding (this serializer does not rely on the JVM for character
* encoding, you can look into the <code>cocoon-serializers-charsets</code>
* JAR file for a list).<p>
*
* <p>The value indicated by <i>myindenting</i> will control the indenting
* level for each element.<p>
*
* <p>The value indicated by <em>setContentLength</em> determines if the serializer
* sets the <code>Content-Length</code> HTTP header. The parameter is optional, the
* default value is <em>false</em>.
*
* @version CVS $Id$
*/
public abstract class EncodingSerializer implements Serializer, Locator, Recyclable, Configurable {
/** The line separator string */
private static final char S_EOL[] = SystemUtils.LINE_SEPARATOR.toCharArray();
/* ====================================================================== */
/** The position of the namespace URI in the attributes array. */
public static final int ATTRIBUTE_NSURI = 0;
/** The position of the local name in the attributes array. */
public static final int ATTRIBUTE_LOCAL = 1;
/** The position of the qualified name in the attributes array. */
public static final int ATTRIBUTE_QNAME = 2;
/** The position of the value in the attributes array. */
public static final int ATTRIBUTE_VALUE = 3;
/** The length of the array of strings representing an attribute. */
public static final int ATTRIBUTE_LENGTH = 4;
/* ====================================================================== */
/** Our <code>Encoder</code> instance. */
private Encoder encoder = null;
/** Our <code>Locator</code> instance. */
private Locator locator = null;
/** Our <code>Writer</code> instance. */
private OutputStreamWriter out = null;
/** Flag indicating if the document prolog is being processed. */
private boolean prolog = true;
/** Flag indicating if the document is being processed. */
private boolean processing = false;
/** Current nesting level */
private int level = 0;
/** Whitespace buffer for indentation */
private char[] indentBuffer = null;
/* ====================================================================== */
/** The <code>Charset</code> associated with the character encoding. */
protected Charset charset = null;
/** The <code>Namespace</code> associated with this instance. */
protected Namespaces namespaces = new Namespaces();
/** Per level indent spaces */
protected int indentPerLevel = 0;
/* ====================================================================== */
/** Determine if the serializer should set the Content-Length HTTP header. */
private boolean setContentLength;
/**
* Create a new instance of this <code>EncodingSerializer</code>
*/
protected EncodingSerializer(Encoder encoder) {
super();
this.encoder = encoder;
this.recycle();
}
/* ====================================================================== */
/**
* Test if the component wants to set the content length.
*/
public boolean shouldSetContentLength() {
return this.setContentLength;
}
/**
* Reset this <code>EncodingSerializer</code>.
*/
public void recycle() {
if (processing) throw new IllegalStateException();
this.namespaces = new Namespaces();
this.locator = null;
this.out = null;
this.prolog = true;
if (this.encoder instanceof XMLEncoder) ((XMLEncoder) this.encoder).reset();
}
/**
* Set the <code>OutputStream</code> where this serializer will
* write data to.
*
* @param out The <code>OutputStream</code> used for output.
*/
public void setOutputStream(OutputStream out)
throws IOException {
if (out == null) throw new NullPointerException("Null output");
this.out = new OutputStreamWriter(out, this.charset.getName());
}
/**
* Set the configurations for this serializer.
*/
public void configure(Configuration conf)
throws ConfigurationException {
String encoding = conf.getChild("encoding").getValue(null);
try {
this.charset = CharsetFactory.newInstance().getCharset(encoding);
} catch (UnsupportedEncodingException exception) {
throw new ConfigurationException("Encoding not supported: "
+ encoding, exception);
}
indentPerLevel = conf.getChild("indent").getValueAsInteger(0);
if (indentPerLevel > 0) {
assureIndentBuffer(indentPerLevel * 6);
}
this.setContentLength = conf.getChild("setContentLength").getValueAsBoolean(false);
}
/* ====================================================================== */
private char[] assureIndentBuffer( int size ) {
if (indentBuffer == null || indentBuffer.length < size) {
indentBuffer = new char[size];
Arrays.fill(indentBuffer,' ');
}
return indentBuffer;
}
/**
* Encode and write a <code>String</code>
*/
protected void encode(String data)
throws SAXException {
char array[] = data.toCharArray();
this.encode(array, 0, array.length);
}
/**
* Encode and write an array of characters.
*/
protected void encode(char data[])
throws SAXException {
this.encode(data, 0, data.length);
}
/**
* Encode and write a specific part of an array of characters.
*/
protected void encode(char data[], int start, int length)
throws SAXException {
int end = start + length;
if (data == null) throw new NullPointerException("Null data");
if ((start < 0) || (start > data.length) || (length < 0) ||
(end > data.length) || (end < 0))
throw new IndexOutOfBoundsException("Invalid data");
if (length == 0) return;
for (int x = start; x < end; x++) {
char c = data[x];
if (this.charset.allows(c) && this.encoder.allows(c)) {
continue;
}
if (start != x) this.write(data, start, x - start );
this.write(this.encoder.encode(c));
start = x + 1;
continue;
}
if (start != end) this.write(data, start, end - start );
}
/* ====================================================================== */
/**
* Receive an object for locating the origin of SAX document events.
*/
public final void setDocumentLocator(Locator locator) {
this.locator = locator;
}
/**
* Return the public identifier for the current document event.
*
* @return A <code>String</code> containing the public identifier,
* or <b>null</b> if none is available.
*/
public String getPublicId() {
return(this.locator == null? null: this.locator.getPublicId());
}
/**
* Return the system identifier for the current document event.
*
* @return A <code>String</code> containing the system identifier,
* or <b>null</b> if none is available.
*/
public String getSystemId() {
return(this.locator == null? null: this.locator.getSystemId());
}
/**
* Return the line number where the current document event ends.
*
* @return The line number, or -1 if none is available.
*/
public int getLineNumber() {
return(this.locator == null? -1: this.locator.getLineNumber());
}
/**
* Return the column number where the current document event ends.
*
* @return The column number, or -1 if none is available.
*/
public int getColumnNumber() {
return(this.locator == null? -1: this.locator.getColumnNumber());
}
/**
* Return a <code>String</code> describing the current location.
*/
protected String getLocation() {
if (this.locator == null) return("");
StringBuffer buf = new StringBuffer(" (");
if (this.getSystemId() != null) {
buf.append(this.getSystemId());
buf.append(' ');
}
buf.append("line " + this.getLineNumber());
buf.append(" col " + this.getColumnNumber());
buf.append(')');
return(buf.toString());
}
/* ====================================================================== */
/**
* Flush the stream.
*/
protected void flush()
throws SAXException {
try {
this.out.flush();
} catch (IOException e) {
throw new SAXException("I/O error flushing: " + e.getMessage(), e);
}
}
/**
* Write an array of characters.
*/
protected void write(char data[])
throws SAXException {
try {
this.out.write(data, 0, data.length);
} catch (IOException e) {
throw new SAXException("I/O error writing: " + e.getMessage(), e);
}
}
/**
* Write a portion of an array of characters.
*/
protected void write(char data[], int start, int length)
throws SAXException {
try {
this.out.write(data, start, length);
} catch (IOException e) {
throw new SAXException("I/O error writing: " + e.getMessage(), e);
}
}
/**
* Write a single character.
*/
protected void write(int c)
throws SAXException {
try {
this.out.write(c);
} catch (IOException e) {
throw new SAXException("I/O error writing: " + e.getMessage(), e);
}
}
/**
* Write a string.
*/
protected void write(String data)
throws SAXException {
try {
this.out.write(data);
} catch (IOException e) {
throw new SAXException("I/O error writing: " + e.getMessage(), e);
}
}
/**
* Write a portion of a string.
*/
protected void write(String data, int start, int length)
throws SAXException {
try {
this.out.write(data, start, length);
} catch (IOException e) {
throw new SAXException("I/O error writing: " + e.getMessage(), e);
}
}
/**
* Write a end-of-line character.
*/
protected void writeln()
throws SAXException {
try {
this.out.write(S_EOL);
} catch (IOException e) {
throw new SAXException("I/O error writing: " + e.getMessage(), e);
}
}
/**
* Write a string and a end-of-line character.
*/
protected void writeln(String data)
throws SAXException {
try {
this.out.write(data);
this.out.write(S_EOL);
} catch (IOException e) {
throw new SAXException("I/O error writing: " + e.getMessage(), e);
}
}
/**
* Write out character to indent the output according
* to the level of nesting
* @param indent
* @throws SAXException
*/
protected void writeIndent(int indent) throws SAXException {
this.charactersImpl("\n".toCharArray(),0,1);
if (indent > 0) {
this.charactersImpl(assureIndentBuffer(indent),0,indent);
}
}
/* ====================================================================== */
/**
* Receive notification of the beginning of a document.
*/
public void startDocument()
throws SAXException {
this.processing = true;
this.level = 0;
}
/**
* Receive notification of the end of a document.
*/
public void endDocument()
throws SAXException {
this.processing = false;
this.flush();
}
/**
* Begin the scope of a prefix-URI Namespace mapping.
*/
public void startPrefixMapping(String prefix, String uri)
throws SAXException {
this.namespaces.push(prefix, uri);
}
/**
* End the scope of a prefix-URI mapping.
*/
public void endPrefixMapping(String prefix)
throws SAXException {
this.namespaces.pop(prefix);
}
/**
* Receive notification of the beginning of an element.
*/
public void startElement(String nsuri, String local, String qual,
Attributes attributes)
throws SAXException {
if (indentPerLevel > 0) {
this.writeIndent(indentPerLevel*level);
level++;
}
String name = this.namespaces.qualify(nsuri, local, qual);
if (this.prolog) {
this.body(nsuri, local, name);
this.prolog = false;
}
String ns[][] = this.namespaces.commit();
String at[][] = new String [attributes.getLength()][4];
for (int x = 0; x < at.length; x++) {
at[x][ATTRIBUTE_NSURI] = attributes.getURI(x);
at[x][ATTRIBUTE_LOCAL] = attributes.getLocalName(x);
at[x][ATTRIBUTE_QNAME] = namespaces.qualify(
attributes.getURI(x),
attributes.getLocalName(x),
attributes.getQName(x));
at[x][ATTRIBUTE_VALUE] = attributes.getValue(x);
}
this.startElementImpl(nsuri, local, name, ns, at);
}
public void characters (char ch[], int start, int length)
throws SAXException {
if (indentPerLevel > 0) {
this.writeIndent(indentPerLevel*level + 1);
}
this.charactersImpl(ch, start, length);
}
/**
* Receive notification of the end of an element.
*/
public void endElement(String nsuri, String local, String qual)
throws SAXException {
if (indentPerLevel > 0) {
level--;
this.writeIndent(indentPerLevel*level);
}
String name = this.namespaces.qualify(nsuri, local, qual);
this.endElementImpl(nsuri, local, name);
}
/**
* Receive notification of the beginning of the document body.
*
* @param uri The namespace URI of the root element.
* @param local The local name of the root element.
* @param qual The fully-qualified name of the root element.
*/
public abstract void body(String uri, String local, String qual)
throws SAXException;
/**
* Receive notification of the beginning of an element.
*
* @param uri The namespace URI of the root element.
* @param local The local name of the root element.
* @param qual The fully-qualified name of the root element.
* @param namespaces An array of <code>String</code> objects containing
* the namespaces to be declared by this element.
* @param attributes An array of <code>String</code> objects containing
* all attributes of this element.
*/
public abstract void startElementImpl(String uri, String local, String qual,
String namespaces[][], String attributes[][])
throws SAXException;
/**
* Receive character notifications
* @param ch
* @param start
* @param length
* @throws SAXException
*/
public abstract void charactersImpl (char ch[], int start, int length)
throws SAXException;
/**
* Receive notification of the end of an element.
*
* @param uri The namespace URI of the root element.
* @param local The local name of the root element.
* @param qual The fully-qualified name of the root element.
*/
public abstract void endElementImpl(String uri, String local, String qual)
throws SAXException;
}