source: contrib/MailArchiver/sources/vendor/mime4j/custom/dom/src/main/javacc/org/apache/james/mime4j/field/structured/StructuredFieldParser.jj @ 6785

/****************************************************************
 * 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.                                           *
 ****************************************************************/

options {
  static=false;
  JDK_VERSION = "1.5";
  OUTPUT_DIRECTORY = "../../../../../../../../../target/generated-sources/javacc";
  //DEBUG_PARSER = true;
  //DEBUG_TOKEN_MANAGER = true;
}

PARSER_BEGIN(StructuredFieldParser)
/****************************************************************
 * 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.field.structured.parser;

/**
 * Parses generic structure fields.
 * Unfolds and removes comments.
 */
public class StructuredFieldParser {
        
        private boolean preserveFolding = false;
        
        /**
         * Should the \r\n folding sequence be preserved?
         */
        public boolean isFoldingPreserved() {
                return preserveFolding;
        }
        
        /**
         * Sets whether the \r\n folding sequence should be preserved.
         */
        public void setFoldingPreserved(boolean preserveFolding) {
                this.preserveFolding =  preserveFolding;
        }
        
        /**
         * Unfolds the input and removes comments.
         * @return unfolded header value with comments removed
         */
        public String parse() throws ParseException {
                try {
                        return doParse();
                } catch (TokenMgrError e) {
                        // An issue with the TOKENiser 
                        // but it's not polite to throw an Error
                        // when executing on a server
                        throw new ParseException(e);
                }
        }
}
PARSER_END(StructuredFieldParser)

private String doParse() :
{
        Token t;
        StringBuffer buffer = new StringBuffer(50);
        boolean whitespace = false;
        boolean first = true;
}
{
        ( 
                t = <CONTENT> 
                        {
                                if (first) {
                                        first = false;
                                } else if (whitespace) {
                                        buffer.append(" ");
                                        whitespace = false;
                                }
                                buffer.append(t.image);
                        }
                | 
                t = <STRING_CONTENT>
                        {
                                buffer.append(t.image);
                        }
                |
                t = <QUOTEDSTRING>
                        {
                                if (first) {
                                        first = false;
                                } else if (whitespace) {
                                        buffer.append(" ");
                                        whitespace = false;
                                }
                                buffer.append(t.image);
                        }
                |
                t = <FOLD>
                        {
                                if (preserveFolding) buffer.append("\r\n");
                        }
                |
                t = <WS> 
                        {
                                whitespace = true;      
                        }
        )*
        {return buffer.toString();}
}

TOKEN_MGR_DECLS :
{
        // Keeps track of how many levels of comment nesting
        // we've encountered.  This is only used when the 2nd
        // level is reached, for example ((this)), not (this).
        // This is because the outermost level must be treated
        // specially anyway, because the outermost ")" has a
        // different token type than inner ")" instances.
        int commentNest;
}


SKIP :
{
        // starts a comment
        "(" : INCOMMENT
}

<INCOMMENT> SKIP :
{
        // ends a comment
        ")" : DEFAULT
        // if this is ever changed to not be a SKIP, need
        // to make sure matchedToken.token = token.toString()
        // is called.
}

<INCOMMENT> SKIP :
{
  "(" { commentNest = 1; } : NESTED_COMMENT
}

<INCOMMENT> SKIP :
{
  <~[ "(", ")" ]>
}

<NESTED_COMMENT> SKIP:
{
        "(" { ++commentNest; }
|       ")" { --commentNest; if (commentNest == 0) SwitchTo(INCOMMENT); }
}

<NESTED_COMMENT> SKIP :
{
        < <QUOTEDPAIR>> { image.deleteCharAt(image.length() - 2); }
}

<NESTED_COMMENT> SKIP:
{
        <~[ "(", ")" ]>
}

// QUOTED STRINGS

SKIP :
{
        "\"" : INQUOTEDSTRING
}

<INQUOTEDSTRING> MORE :
{
        < <QUOTEDPAIR> > { image.deleteCharAt(image.length() - 2); }
}

<INQUOTEDSTRING> TOKEN :
{
        < STRING_CONTENT : (~["\"", "\\", "\r"])+ >
        // Preserve line break within quotes but not trailing white space
|       < FOLD: "\r\n" ( [" ", "\t"] )* >
|       < QUOTEDSTRING: "\"" > { matchedToken.image = image.substring(0, image.length() - 1); } : DEFAULT
}

<DEFAULT>
TOKEN :
{
        < WS: ( [" ", "\t", "\r", "\n"] )+ >
}

<DEFAULT>
TOKEN :
{
        < CONTENT: (~[" ", "\t", "\r", "\n", "(", "\""])+ >
}

<*>
TOKEN :
{
        < #QUOTEDPAIR: "\\" <ANY> >
|       < #ANY: (~[])+ >
}