X-Git-Url: http://git.megacz.com/?p=sbp.git;a=blobdiff_plain;f=src%2Fedu%2Fberkeley%2Fsbp%2FAtom.java;h=0a8ad12132a07d859244febaf899110e52cec038;hp=1b9c25430f017f039c0701c74feed92cfc73736a;hb=d28917b3c84c429e8fd6587717df9e90a894b18f;hpb=6caa23ec64fa689a91c0b81238d04ff7322a945c diff --git a/src/edu/berkeley/sbp/Atom.java b/src/edu/berkeley/sbp/Atom.java index 1b9c254..0a8ad12 100644 --- a/src/edu/berkeley/sbp/Atom.java +++ b/src/edu/berkeley/sbp/Atom.java @@ -7,39 +7,19 @@ import edu.berkeley.sbp.util.*; import edu.berkeley.sbp.*; import edu.berkeley.sbp.*; -/** an element which matches exactly one input token */ -public abstract class Atom extends Element implements Topology { - - private final Topology rt; - - public Atom(Topology rt) { this.rt = rt; } - - void reachable(HashSet h) { /* do-nothing */ } - - /** equality is based on the underlying Topology */ - public int hashCode() { return rt.hashCode(); } - - /** equality is based on the underlying Topology */ - public boolean equals(Object o) { return o != null && o instanceof Atom && ((Atom)o).rt.equals(rt); } - - /** declared abstract to force subclasses to override it in a useful manner */ - public abstract String toString(); - - // Topology Thunks ////////////////////////////////////////////////////////////////////////////// - - public void add(Topology t) { rt.add(t); } - public void add(T t) { rt.add(t); } - public void remove(Topology t) { rt.remove(t); } - public void remove(T t) { rt.remove(t); } - public Topology dup() { return rt.dup(); } - public boolean contains(T v) { return rt.contains(v); } - public Topology fresh() { return rt.fresh(); } - public Topology intersect(Topology t) { return rt.intersect(t); } - public Topology minus(Topology t) { return rt.minus(t); } - public Topology union(Topology t) { return rt.union(t); } - public Topology complement() { return rt.complement(); } - public boolean disjoint(Topology t) { return rt.disjoint(t); } - public boolean containsAll(Topology t) { return rt.containsAll(t); } - +/** + * an element which matches some set of one-token-long input strings. + * + * This class is a topology over itself so that Atoms can be + * intersected and unioned with each other to result in other + * Atom's (rather than raw Topology's, which are not Elements). + * If you want the latter, use the getTokenTopology() method. + */ +public abstract class Atom extends Element implements Topology> { + + /** the set (topology) of tokens that can match this element */ + public abstract Topology getTokenTopology(); + + public abstract StringBuffer toString(StringBuffer sb); }