/****************************************************************
* 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.james.mime4j.parser;
import org.apache.james.mime4j.MimeException;
import org.apache.james.mime4j.descriptor.BodyDescriptor;
import java.io.IOException;
import java.io.InputStream;
/**
* <p>
* Parses MIME (or RFC822) message streams of bytes or characters and reports
* parsing events to a <code>ContentHandler</code> instance.
* </p>
* <p>
* Typical usage:<br/>
* <pre>
* ContentHandler handler = new MyHandler();
* MimeStreamParser parser = new MimeStreamParser();
* parser.setContentHandler(handler);
* parser.parse(new FileInputStream("mime.msg"));
* </pre>
*
* @version $Id: MimeStreamParser.java,v 1.8 2005/02/11 10:12:02 ntherning Exp $
*/
public class MimeStreamParser {
private ContentHandler handler = null;
private boolean contentDecoding;
private final MimeTokenStream mimeTokenStream = new MimeTokenStream();
public MimeStreamParser() {
super();
this.contentDecoding = false;
}
/**
* Determines whether this parser automatically decodes body content
* based on the on the MIME fields with the standard defaults.
*/
public boolean isContentDecoding() {
return contentDecoding;
}
/**
* Defines whether parser should automatically decode body content
* based on the on the MIME fields with the standard defaults.
*/
public void setContentDecoding(boolean b) {
this.contentDecoding = b;
}
/**
* Parses a stream of bytes containing a MIME message.
*
* @param is the stream to parse.
* @throws MimeException if the message can not be processed
* @throws IOException on I/O errors.
*/
public void parse(InputStream is) throws MimeException, IOException {
mimeTokenStream.parse(is);
OUTER: for (;;) {
int state = mimeTokenStream.getState();
switch (state) {
case MimeTokenStream.T_BODY:
BodyDescriptor desc = mimeTokenStream.getBodyDescriptor();
InputStream bodyContent;
if (contentDecoding) {
bodyContent = mimeTokenStream.getDecodedInputStream();
} else {
bodyContent = mimeTokenStream.getInputStream();
}
handler.body(desc, bodyContent);
break;
case MimeTokenStream.T_END_BODYPART:
handler.endBodyPart();
break;
case MimeTokenStream.T_END_HEADER:
handler.endHeader();
break;
case MimeTokenStream.T_END_MESSAGE:
handler.endMessage();
break;
case MimeTokenStream.T_END_MULTIPART:
handler.endMultipart();
break;
case MimeTokenStream.T_END_OF_STREAM:
break OUTER;
case MimeTokenStream.T_EPILOGUE:
handler.epilogue(mimeTokenStream.getInputStream());
break;
case MimeTokenStream.T_FIELD:
handler.field(mimeTokenStream.getField());
break;
case MimeTokenStream.T_PREAMBLE:
handler.preamble(mimeTokenStream.getInputStream());
break;
case MimeTokenStream.T_RAW_ENTITY:
handler.raw(mimeTokenStream.getInputStream());
break;
case MimeTokenStream.T_START_BODYPART:
handler.startBodyPart();
break;
case MimeTokenStream.T_START_HEADER:
handler.startHeader();
break;
case MimeTokenStream.T_START_MESSAGE:
handler.startMessage();
break;
case MimeTokenStream.T_START_MULTIPART:
handler.startMultipart(mimeTokenStream.getBodyDescriptor());
break;
default:
throw new IllegalStateException("Invalid state: " + state);
}
state = mimeTokenStream.next();
}
}
/**
* Determines if this parser is currently in raw mode.
*
* @return <code>true</code> if in raw mode, <code>false</code>
* otherwise.
* @see #setRaw(boolean)
*/
public boolean isRaw() {
return mimeTokenStream.isRaw();
}
/**
* Enables or disables raw mode. In raw mode all future entities
* (messages or body parts) in the stream will be reported to the
* {@link ContentHandler#raw(InputStream)} handler method only.
* The stream will contain the entire unparsed entity contents
* including header fields and whatever is in the body.
*
* @param raw <code>true</code> enables raw mode, <code>false</code>
* disables it.
*/
public void setRaw(boolean raw) {
mimeTokenStream.setRecursionMode(MimeTokenStream.M_RAW);
}
/**
* Finishes the parsing and stops reading lines.
* NOTE: No more lines will be parsed but the parser
* will still call
* {@link ContentHandler#endMultipart()},
* {@link ContentHandler#endBodyPart()},
* {@link ContentHandler#endMessage()}, etc to match previous calls
* to
* {@link ContentHandler#startMultipart(BodyDescriptor)},
* {@link ContentHandler#startBodyPart()},
* {@link ContentHandler#startMessage()}, etc.
*/
public void stop() {
mimeTokenStream.stop();
}
/**
* Sets the <code>ContentHandler</code> to use when reporting
* parsing events.
*
* @param h the <code>ContentHandler</code>.
*/
public void setContentHandler(ContentHandler h) {
this.handler = h;
}
}