1 // Copyright 2006 all rights reserved; see LICENSE file for BSD-style license
3 package edu.berkeley.sbp.chr;
6 import java.lang.reflect.*;
7 import java.lang.ref.*;
8 import edu.berkeley.sbp.*;
9 import edu.berkeley.sbp.util.*;
10 import edu.berkeley.sbp.misc.*;
11 import edu.berkeley.sbp.Input.Location;
13 public class CharAtom extends Atom<Character> {
15 public CharAtom() { this(new CharTopology()); }
16 public CharAtom(char a) { this(a,a); }
17 public CharAtom(char a, char b) { this(new CharTopology(a, b)); }
18 public CharAtom(CharTopology t) { this.t = t; }
19 public CharAtom(Topology<Character> t) { this(t instanceof CharTopology ? (CharTopology)t : new CharTopology(t)); }
21 private CharTopology t;
22 public Topology<Character> top() { return t; }
24 public static final char left = (char)9998;
25 public static final char right = (char)9999;
26 public static final Atom leftBrace = new CharAtom(left,left) { public String toString() { return "\\{"; } };
27 public static final Atom rightBrace = new CharAtom(right,right) { public String toString() { return "\\}"; } };
28 public static final Atom braces = new CharAtom(left,right) { public String toString() { return "[\\{\\}]"; } };
30 public static Atom set(Range.Set r) { return new CharAtom(new CharTopology(r)); }
31 public String toString() { return t.toString(); }
33 /** returns an element which exactly matches the string given */
34 public static Element string(String s) { return string(s, true); }
35 public static Element string(String s, boolean share) {
36 if (share && s.length() == 0) return epsilon;
37 final String escapified = "\""+StringUtil.escapify(s, "\"\r\n\\")+"\"";
39 if (share && s.length() == 1) {
41 new CharAtom(s.charAt(0)) {
42 public String toString() { return escapified; } };
44 Union ret2 = new Union("\""+s+"\"_str", true) {
45 public String toString() { return escapified; } };
46 Element[] refs = new Element[s.length()];
47 for(int i=0; i<refs.length; i++) refs[i] = new CharAtom(s.charAt(i));
48 ret2.add(Sequence.create(refs, s));
54 private static Union epsilon = new Union("()");
55 static { epsilon.add(Sequence.create()); }
57 public Topology<Atom<Character>> unwrap() { return this; }
58 public Topology<Atom<Character>> empty() { return new CharAtom(); }
59 public Topology<Character> getTokenTopology() { return top(); }
61 public boolean contains(Atom<Character> v) { return top().containsAll(((CharAtom)v).top()); }
62 public boolean disjoint(Topology<Atom<Character>> t) { return top().disjoint(((CharAtom)t).top()); }
63 public boolean containsAll(Topology<Atom<Character>> t) { return top().containsAll(((CharAtom)t).top()); }
65 public Topology<Atom<Character>> complement() { return new CharAtom(top().complement()); }
66 public Topology<Atom<Character>> intersect(Topology<Atom<Character>> t) { return new CharAtom(top().intersect(((CharAtom)t).top())); }
67 public Topology<Atom<Character>> minus(Topology<Atom<Character>> t) { return new CharAtom(top().minus(((CharAtom)t).top())); }
68 public Topology<Atom<Character>> union(Topology<Atom<Character>> t) { return new CharAtom(top().union(((CharAtom)t).top())); }
70 public int hashCode() { return top().hashCode(); }
71 public boolean equals(Object o) { return o != null && (o instanceof CharAtom) && ((CharAtom)o).top().equals(top()); }