| /* |
| * Copyright 2005-2006 Sun Microsystems, Inc. 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. Sun designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| * CA 95054 USA or visit www.sun.com if you need additional information or |
| * have any questions. |
| */ |
| package com.sun.xml.internal.rngom.binary; |
| |
| public class PatternBuilder { |
| private final EmptyPattern empty; |
| protected final NotAllowedPattern notAllowed; |
| protected final PatternInterner interner; |
| |
| public PatternBuilder() { |
| empty = new EmptyPattern(); |
| notAllowed = new NotAllowedPattern(); |
| interner = new PatternInterner(); |
| } |
| |
| public PatternBuilder(PatternBuilder parent) { |
| empty = parent.empty; |
| notAllowed = parent.notAllowed; |
| interner = new PatternInterner(parent.interner); |
| } |
| |
| Pattern makeEmpty() { |
| return empty; |
| } |
| |
| Pattern makeNotAllowed() { |
| return notAllowed; |
| } |
| |
| Pattern makeGroup(Pattern p1, Pattern p2) { |
| if (p1 == empty) |
| return p2; |
| if (p2 == empty) |
| return p1; |
| if (p1 == notAllowed || p2 == notAllowed) |
| return notAllowed; |
| if (false && p1 instanceof GroupPattern) { |
| GroupPattern sp = (GroupPattern)p1; |
| return makeGroup(sp.p1, makeGroup(sp.p2, p2)); |
| } |
| Pattern p = new GroupPattern(p1, p2); |
| return interner.intern(p); |
| } |
| |
| Pattern makeInterleave(Pattern p1, Pattern p2) { |
| if (p1 == empty) |
| return p2; |
| if (p2 == empty) |
| return p1; |
| if (p1 == notAllowed || p2 == notAllowed) |
| return notAllowed; |
| if (false && p1 instanceof InterleavePattern) { |
| InterleavePattern ip = (InterleavePattern)p1; |
| return makeInterleave(ip.p1, makeInterleave(ip.p2, p2)); |
| } |
| if (false) { |
| if (p2 instanceof InterleavePattern) { |
| InterleavePattern ip = (InterleavePattern)p2; |
| if (p1.hashCode() > ip.p1.hashCode()) |
| return makeInterleave(ip.p1, makeInterleave(p1, ip.p2)); |
| } |
| else if (p1.hashCode() > p2.hashCode()) |
| return makeInterleave(p2, p1); |
| } |
| Pattern p = new InterleavePattern(p1, p2); |
| return interner.intern(p); |
| } |
| |
| Pattern makeChoice(Pattern p1, Pattern p2) { |
| if (p1 == empty && p2.isNullable()) |
| return p2; |
| if (p2 == empty && p1.isNullable()) |
| return p1; |
| Pattern p = new ChoicePattern(p1, p2); |
| return interner.intern(p); |
| } |
| |
| Pattern makeOneOrMore(Pattern p) { |
| if (p == empty |
| || p == notAllowed |
| || p instanceof OneOrMorePattern) |
| return p; |
| Pattern p1 = new OneOrMorePattern(p); |
| return interner.intern(p1); |
| } |
| |
| Pattern makeOptional(Pattern p) { |
| return makeChoice(p, empty); |
| } |
| |
| Pattern makeZeroOrMore(Pattern p) { |
| return makeOptional(makeOneOrMore(p)); |
| } |
| } |