1 package edu.berkeley.sbp.misc;
4 import java.lang.reflect.*;
5 import java.lang.ref.*;
6 import edu.berkeley.sbp.*;
7 import edu.berkeley.sbp.Input.Location;
8 import edu.berkeley.sbp.util.*;
10 /** an implementation of Input for streams of Java <tt>char</tt> values */
11 public class StringInput {
13 public static final StringInput left = new StringInput(null, null) { public boolean equals(Object o) { return this==o; } };
14 public static final StringInput right = new StringInput(null, null) { public boolean equals(Object o) { return this==o; } };
16 public static final Atom leftBrace = new StringAtom(new DiscreteTopology<StringInput>(left)) { public String toString() { return "{"; } };
17 public static final Atom rightBrace = new StringAtom(new DiscreteTopology<StringInput>(right)) { public String toString() { return "}"; } };
19 private static class StringAtom extends Atom {
22 public StringAtom(String s) { this.t = new DiscreteTopology<StringInput>(new StringInput(s, null)); this.s = s; }
23 public StringAtom(Topology<StringInput> t) { this.t = t; }
24 public String toString() { return "[atom \""+s+"\"]"; }
25 public Topology top() { return t; }
28 /** returns an element which exactly matches the string given */
29 public static Element string(String s) {
30 return new StringAtom(s);
33 public static Topology<StringInput> top() { return new DiscreteTopology<StringInput>(); }
35 public final String s;
36 public final Location location;
37 private StringInput(String s, Location loc) { this.s = s; this.location = loc; }
38 public String result() { return s; }
39 public Location getLocation() { return location; }
40 public String toString() { return "\'"+StringUtil.escapify(s)+"\'"; }
42 public boolean equals(Object o) { return o!=null && o instanceof StringInput && s.equals(((StringInput)o).s); }
43 public int hashCode() { return s==null ? 0 : s.hashCode(); }