resolver/src/main/java/org/apache/james/jspf/core/SPFTermsRegexps.java

/****************************************************************
 * 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.jspf.core;

/**
 * This constants are used by Terms to define their matching rules.
 */
public interface SPFTermsRegexps {
    

    final String ALPHA_PATTERN = "[a-zA-Z]";

    final String MACRO_LETTER_PATTERN_EXP = "[rctlsodipvhRCTLSODIPVH]";

    final String MACRO_LETTER_PATTERN = "[lsodipvhLSODIPVH]";

    final String TRANSFORMERS_REGEX = "\\d*[r]?";

    final String DELEMITER_REGEX = "[\\.\\-\\+,/_\\=]";

    final String MACRO_LETTERS_REGEX = MACRO_LETTER_PATTERN_EXP + TRANSFORMERS_REGEX + DELEMITER_REGEX + "*";

    final String MACRO_EXPAND_REGEX = "\\%(?:\\{"
            + MACRO_LETTERS_REGEX + "\\}|\\%|\\_|\\-)";

    final String MACRO_LITERAL_REGEX = "[\\x21-\\x24\\x26-\\x7e]";

    /**
     * This is used by the MacroExpander
     */
    final String MACRO_STRING_REGEX_TOKEN = MACRO_EXPAND_REGEX
    + "|" + MACRO_LITERAL_REGEX + "{1}";


    /**
     * ABNF: macro-string = *( macro-expand / macro-literal )
     */
    final String MACRO_STRING_REGEX = "(?:" + MACRO_STRING_REGEX_TOKEN +")*";

    final String ALPHA_DIGIT_PATTERN = "[a-zA-Z0-9]";

    /**
     * ABNF: toplabel = ( *alphanum ALPHA *alphanum ) / ( 1*alphanum "-" *(
     * alphanum / "-" ) alphanum ) ; LDH rule plus additional TLD restrictions ;
     * (see [RFC3696], Section 2)
     */
    final String TOP_LABEL_REGEX = "(?:"
            + ALPHA_DIGIT_PATTERN + "*" + SPFTermsRegexps.ALPHA_PATTERN
            + "{1}" + ALPHA_DIGIT_PATTERN + "*|(?:"
            + ALPHA_DIGIT_PATTERN + "+" + "\\-" + "(?:"
            + ALPHA_DIGIT_PATTERN + "|\\-)*"
            + ALPHA_DIGIT_PATTERN + "))";

    /**
     * ABNF: domain-end = ( "." toplabel [ "." ] ) / macro-expand
     */
    final String DOMAIN_END_REGEX = "(?:\\." + TOP_LABEL_REGEX
            + "\\.?" + "|" + SPFTermsRegexps.MACRO_EXPAND_REGEX + ")";

    /**
     * ABNF: domain-spec = macro-string domain-end
     */
    final String DOMAIN_SPEC_REGEX = "("
            + SPFTermsRegexps.MACRO_STRING_REGEX + DOMAIN_END_REGEX + ")";

    /**
     * Spring MACRO_STRING from DOMAIN_END (domain end starts with .)
     */
    final String DOMAIN_SPEC_REGEX_R = "("
            + SPFTermsRegexps.MACRO_STRING_REGEX + ")(" + DOMAIN_END_REGEX + ")";


}