X-Git-Url: http://git.megacz.com/?p=sbp.git;a=blobdiff_plain;f=src%2Fedu%2Fberkeley%2Fsbp%2FAtom.java;h=a9e89814225a8de049de9e2f062ddad58f09f13b;hp=0a8ad12132a07d859244febaf899110e52cec038;hb=HEAD;hpb=d28917b3c84c429e8fd6587717df9e90a894b18f diff --git a/src/edu/berkeley/sbp/Atom.java b/src/edu/berkeley/sbp/Atom.java index 0a8ad12..a9e8981 100644 --- a/src/edu/berkeley/sbp/Atom.java +++ b/src/edu/berkeley/sbp/Atom.java @@ -1,25 +1,29 @@ +// (C) 2006-2007 all rights reserved; see LICENSE file for BSD-style license + package edu.berkeley.sbp; -import java.io.*; -import java.util.*; -import java.lang.reflect.*; -import java.lang.ref.*; import edu.berkeley.sbp.util.*; -import edu.berkeley.sbp.*; -import edu.berkeley.sbp.*; /** - * an element which matches some set of one-token-long input strings. + * + * 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. + *

+ * This class is a topology over itself (yes, this is impredicative). + * This means that you can call Atom.union(Atom) and get back an Atom. + * If you are interested in the topology of tokens which this + * Atom can match, use the getTokenTopology() method. + *

*/ -public abstract class Atom extends Element implements Topology> { +public abstract class Atom + extends Element + implements Topology> { /** the set (topology) of tokens that can match this element */ - public abstract Topology getTokenTopology(); + public abstract Topology getTokenTopology(); + + StringBuffer toString(StringBuffer sb) { sb.append(this); return sb; } - public abstract StringBuffer toString(StringBuffer sb); } +