1 /*

     2  * Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Oracle designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Oracle in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    22  * or visit www.oracle.com if you need additional information or have any

    23  * questions.

    24  */

    25 

    26 package org.openjdk.tests.shapegen;

    27 

    28 import java.util.ArrayList;

    29 import java.util.HashMap;

    30 import java.util.List;

    31 import java.util.Map;

    32 import java.io.IOException;

    33 import java.io.StringReader;

    34 

    35 import static java.lang.Character.isLetter;

    36 import static java.lang.Character.isUpperCase;

    37 import static java.lang.Character.isWhitespace;

    38 

    39 /**

    40  * Parse a type template definition string

    41  *

    42  *   input     :: classDef

    43  *   classDef  :: letter [ ( classDef* ) ]

    44  *

    45  * @author Robert Field

    46  */

    47 public class TTParser extends StringReader {

    48 

    49     private Map<Character, TTNode> letterMap = new HashMap<>();

    50     private char ch;

    51 

    52     private final String def;

    53 

    54     public TTParser(String s) {

    55         super(s);

    56         this.def = s;

    57     }

    58 

    59     private void advance() throws IOException {

    60         do {

    61             ch = (char)read();

    62         } while (isWhitespace(ch));

    63     }

    64 

    65     public TTNode parse() {

    66         try {

    67             advance();

    68             return classDef();

    69         } catch (IOException t) {

    70             throw new RuntimeException(t);

    71         }

    72     }

    73 

    74     private TTNode classDef() throws IOException {

    75         if (!isLetter(ch)) {

    76             if (ch == (char)-1) {

    77                 throw new IOException("Unexpected end of type template in " + def);

    78             } else {

    79                 throw new IOException("Unexpected character in type template: " + (Character)ch + " in " + def);

    80             }

    81         }

    82         char nodeCh = ch;

    83         TTNode node = letterMap.get(nodeCh);

    84         boolean canBeClass = isUpperCase(nodeCh);

    85         advance();

    86         if (node == null) {

    87             List<TTNode> subtypes = new ArrayList<>();

    88             if (ch == '(') {

    89                 advance();

    90                 while (ch != ')') {

    91                     subtypes.add(classDef());

    92                 }

    93                 advance();

    94             }

    95             node = new TTNode(subtypes, canBeClass);

    96             letterMap.put(nodeCh, node);

    97         }

    98         return node;

    99     }

   100 }