1 // Copyright 2006 all rights reserved; see LICENSE file for BSD-style license
3 package edu.berkeley.sbp.meta;
4 import edu.berkeley.sbp.util.*;
5 import edu.berkeley.sbp.*;
8 import java.lang.reflect.*;
9 import java.lang.ref.*;
11 /** currently this class exports only static methods to create repetitions; there are no public instance methods or constructors */
12 public class Repeat extends Union {
14 public Repeat(final Element e, boolean zeroOkay, boolean manyOkay, Object tag) {
15 this(e, zeroOkay, manyOkay, null, false, tag); }
16 public Repeat(final Element e, boolean zeroOkay, boolean manyOkay, final Element separator, Object tag) {
17 this(e, zeroOkay, manyOkay, separator, false, tag); }
18 protected Repeat(final Element e, boolean zeroOkay, boolean manyOkay, final Element separator, boolean maximal, Object tag) {
19 this(e, zeroOkay, manyOkay, separator, maximal, tag, null); }
20 protected Repeat(final Element e, boolean zeroOkay, boolean manyOkay, final Element separator, boolean maximal, Object tag, Atom follow) {
25 ? (maximal ? "**" : "*")
26 : (maximal ? "++" : "+")))
31 if (zeroOkay && !manyOkay) {
33 add(Sequence.create(tag, new Element[] { }, null, false).followedBy(follow));
34 add(Sequence.create(tag, new Element[] { e }, null, false).followedBy(follow));
35 } else if (zeroOkay) {
36 add(Sequence.create(tag, new Element[] { }, null, false).followedBy(follow));
37 //add(new Sequence.Constant.Empty());
39 add(Sequence.create(many1(e, separator, tag)).followedBy(follow));
41 add(Sequence.create(tag, new Element[] { e }, null, false).followedBy(follow));
43 add(Sequence.create(tag, new Element[] { e, Repeat.this }, new boolean[] { false, false }, true).followedBy(follow));
45 add(Sequence.create(tag, new Element[] { e, separator, Repeat.this }, new boolean[] { false, true, false }, true).followedBy(follow));
49 public static class Maximal extends Repeat {
50 public Maximal(final Element e, boolean zeroOkay, boolean manyOkay, final Atom separator, Object tag) {
51 super(e, zeroOkay, manyOkay, separator, true, tag, (Atom)separator.complement());
52 if (zeroOkay && separator != null)
53 throw new RuntimeException("cannot create a maximal repetition of zero or more items with a separator (yet): " + this);
55 public Maximal(final Atom e, boolean zeroOkay, boolean manyOkay, Object tag) {
56 super(e, zeroOkay, manyOkay, null, true, tag, (Atom)e.complement());
60 /** repeat zero or one times */
61 public static Element maybe(Element e) { return new Repeat(e, true, false, null, null); }
62 public static Element maybe(Element e, Object tag) { return new Repeat(e, true, false, null, tag); }
63 /** repeat zero or more times */
64 public static Element many0(Element e) { return new Repeat(e, true, true, null, null); }
65 public static Element many0(Element e, Object tag) { return new Repeat(e, true, true, null, tag); }
66 /** repeat zero or more times, separated by <tt>sep</tt> */
67 public static Element many0(Element e, Element sep) { return new Repeat(e, true, true, sep, null); }
68 public static Element many0(Element e, Element sep, Object tag) { return new Repeat(e, true, true, sep, tag); }
69 /** repeat one or more times */
70 public static Element many1(Element e) { return new Repeat(e, false, true, null, null); }
71 public static Element many1(Element e, Object tag) { return new Repeat(e, false, true, null, tag); }
72 /** repeat one or more times, separated by <tt>sep</tt> */
73 public static Element many1(Element e, Element sep) { return new Repeat(e, false, true, sep, null); }
74 public static Element many1(Element e, Element sep, Object tag) { return new Repeat(e, false, true, sep, tag); }
76 /** repeat zero or more times, matching a maximal sequence of atoms */
77 public static Element maximal0(Atom e) { return new Repeat.Maximal(e, true, true, null); }
78 public static Element maximal0(Atom e, Object tag) { return new Repeat.Maximal(e, true, true, tag); }
79 /** repeat one or more times, matching a maximal sequence of atoms */
80 public static Element maximal1(Atom e) { return new Repeat.Maximal(e, false, true, null); }
81 public static Element maximal1(Atom e, Object tag) { return new Repeat.Maximal(e, false, true, tag); }
82 /** repeat one or more times, separated by an atom <tt>sep</tt>, matching a maximal sequence */
83 public static Element maximal1(Element e, Atom sep) { return new Repeat.Maximal(e, false, true, sep, null); }
84 public static Element maximal1(Element e, Atom sep, Object tag) { return new Repeat.Maximal(e, false, true, sep, tag); }
86 public static Element repeatMaximal(Atom e, boolean zero, boolean many, Object tag) {
87 return new Repeat.Maximal(e, zero, many, tag); }
88 public static Element repeatMaximal(Element e, boolean zero, boolean many, Atom sep, Object tag) {
89 return new Repeat.Maximal(e, zero, many, sep, tag); }
90 public static Element repeat(Element e, boolean zero, boolean many, Object tag) {
91 return new Repeat(e, zero, many, tag); }
92 public static Element repeat(Element e, boolean zero, boolean many, Element sep, Object tag) {
93 return new Repeat(e, zero, many, sep, tag); }