/*
 * Copyright (c) 2005, 2015, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package com.sun.tools.javac.util;

import java.util.regex.Pattern;
import javax.lang.model.SourceVersion;

Utilities to convert an import-like string to a regexp.
 
This is NOT part of any supported API.
 If you write code that depends on this, you do so at your own risk.
 This code and its internal interfaces are subject to change or
 deletion without notice.
/**Utilities to convert an import-like string to a regexp.
 *
 *  <p><b>This is NOT part of any supported API.
 *  If you write code that depends on this, you do so at your own risk.
 *  This code and its internal interfaces are subject to change or
 *  deletion without notice.</b>
 */
public class MatchingUtils {

    private static final String allMatchesString = ".*";
    private static final Pattern allMatches = Pattern.compile(allMatchesString);

    
Return true if the argument string is a valid import-style
string specifying claimed annotations; return false otherwise.
/**
     * Return true if the argument string is a valid import-style
     * string specifying claimed annotations; return false otherwise.
     */
    public static boolean isValidImportString(String s) {
        if (s.equals("*"))
            return true;

        boolean valid = true;
        String t = s;
        int index = t.indexOf('*');

        if (index != -1) {
            // '*' must be last character...
            if (index == t.length() -1) {
                // ... any and preceding character must be '.'
                if ( index-1 >= 0 ) {
                    valid = t.charAt(index-1) == '.';
                    // Strip off ".*$" for identifier checks
                    t = t.substring(0, t.length()-2);
                }
            } else
                return false;
        }

        // Verify string is off the form (javaId \.)+ or javaId
        if (valid) {
            String[] javaIds = t.split("\\.", t.length()+2);
            for(String javaId: javaIds)
                valid &= SourceVersion.isIdentifier(javaId);
        }
        return valid;
    }

    public static String validImportStringToPatternString(String s) {
        if (s.equals("*")) {
            return allMatchesString;
        } else {
            String s_prime = s.replace(".", "\\.");

            if (s_prime.endsWith("*")) {
                s_prime =  s_prime.substring(0, s_prime.length() - 1) + ".+";
            }

            return s_prime;
        }
    }

    public static Pattern validImportStringToPattern(String s) {
        String pattern = validImportStringToPatternString(s);

        if (pattern == allMatchesString) {
            return allMatches;
        } else {
            return Pattern.compile(pattern);
        }
    }

}