
/*
 * Janino - An embedded Java[TM] compiler
 *
 * Copyright (c) 2001-2010, Arno Unkrig
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
 * following conditions are met:
 *
 *    1. Redistributions of source code must retain the above copyright notice, this list of conditions and the
 *       following disclaimer.
 *    2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
 *       following disclaimer in the documentation and/or other materials provided with the distribution.
 *    3. The name of the author may not be used to endorse or promote products derived from this software without
 *       specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
 * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

package org.codehaus.janino;

import java.util.*;

/**
 * Representation of a "method descriptor" (JVMS 4.3.3).
 */
@SuppressWarnings({ "rawtypes", "unchecked" }) public
class MethodDescriptor {

    /** The field descriptors of the method parameters. */
    public final String[] parameterFDs;

    /** The field descriptor of the method return value. */
    public final String   returnFD;

    /** */
    public
    MethodDescriptor(String[] parameterFds, String returnFd) {
        this.parameterFDs = parameterFds;
        this.returnFD     = returnFd;
    }

    /**
     * Parse a method descriptor into parameter FDs and return FDs.
     */
    public
    MethodDescriptor(String s) {
        if (s.charAt(0) != '(') throw new JaninoRuntimeException();

        int  from         = 1;
        List parameterFDs = new ArrayList(); // String
        while (s.charAt(from) != ')') {
            int to = from;
            while (s.charAt(to) == '[') ++to;
            if ("BCDFIJSZ".indexOf(s.charAt(to)) != -1) {
                ++to;
            } else
            if (s.charAt(to) == 'L') {
                for (++to; s.charAt(to) != ';'; ++to);
                ++to;
            } else {
                throw new JaninoRuntimeException();
            }
            parameterFDs.add(s.substring(from, to));
            from = to;
        }
        this.parameterFDs = (String[]) parameterFDs.toArray(new String[parameterFDs.size()]);
        this.returnFD     = s.substring(++from);
    }

    /**
     * Returns the "method descriptor" (JVMS 4.3.3).
     */
    @Override public String
    toString() {
        StringBuilder sb = new StringBuilder("(");
        for (int i = 0; i < this.parameterFDs.length; ++i) sb.append(this.parameterFDs[i]);
        return sb.append(')').append(this.returnFD).toString();
    }

    /**
     * Patch an additional parameter into a given method descriptor.
     */
    public static String
    prependParameter(String md, String parameterFd) { return '(' + parameterFd + md.substring(1); }
}
