I did this stuff back in August. It's all in support of EWTS->Tibetan

conversion.  The tag 'TODO(DLC)[EWTS->Tibetan]' exists all over the
place.  EWTS->Tibetan isn't here yet; lexing isn't here yet; this is
mainly a refactoring so that the ACIP->Tibetan code can be reused to
do EWTS->Tibetan.

I'm committing this because tests pass (it shouldn't be breaking
anything), because I want a checkpoint, and because the laptop this
sandbox was on isn't my preferred development environment.

source/org/thdl/tib/text/ttt/TTraits.java

@@ -0,0 +1,70 @@
+/*
+The contents of this file are subject to the THDL Open Community License
+Version 1.0 (the "License"); you may not use this file except in compliance
+with the License. You may obtain a copy of the License on the THDL web site 
+(http://www.thdl.org/).
+
+Software distributed under the License is distributed on an "AS IS" basis, 
+WITHOUT WARRANTY OF ANY KIND, either express or implied. See the 
+License for the specific terms governing rights and limitations under the 
+License. 
+
+The Initial Developer of this software is the Tibetan and Himalayan Digital
+Library (THDL). Portions created by the THDL are Copyright 2003-2004 THDL.
+All Rights Reserved. 
+
+Contributor(s): ______________________________________.
+*/
+
+package org.thdl.tib.text.ttt;
+
+/** A TTraits object encapsulates all the things that make a
+ *  particular Roman transliteration scheme unique.  If both EWTS and
+ *  ACIP transliterations have a property in common, then it's likely
+ *  encoded in a manner that's hard to modify.  But if they differ in
+ *  some respect, then that difference should be encoded in a TTraits
+ *  object.
+ *
+ *  <p>It is very likely that classes that implement this interface
+ *  will choose to use the design pattern 'singleton'. */
+interface TTraits {
+    /** Returns the disambiguator for this transliteration scheme,
+     *  which had better be a string containing just one character
+     *  lest {@link #disambiguatorChar()} become nonsensical for
+     *  certain transliteration systems.  A disambiguator is the
+     *  string that separates two bits of transliteration that would
+     *  otherwise be interpreted differently.  The canonical example
+     *  is EWTS's {gya} versus {g.ya}, which, due to the disambiguator
+     *  in the latter, are different sequences of Unicode. */
+    String disambiguator();
+
+    /** For convenience, a convenience that is possible because ACIP's
+     *  and EWTS's disambiguator strings both have length one, this
+     *  method returns the sole character in the string returned by
+     *  {@link #disambiguator()}. */
+    char disambiguatorChar();
+
+    /** Returns the maximum number of characters of transliteration
+     *  required to denote a Tibetan consonant. */
+    int maxConsonantLength();
+
+    /** Returns the maximum number of characters of transliteration
+     *  required to denote a Tibetan wowel, i.e. a vowel or one or
+     *  more hangers-on like U+TODO(DLC)[EWTS->Tibetan]:_NOW or both. */
+    int maxWowelLength();
+    // TODO(DLC)[EWTS->Tibetan]: use the term 'wowel' everywhere, never "vowel" unless you mean just {e,i,o,u}
+
+    /** Returns true if and only if <em>s</em> is a stretch of
+     *  transliteration corresponding to a Tibetan consonant (without
+     *  any wowel) */
+    boolean isConsonant(String s);
+
+    /** Returns true if and only if <em>s</em> is a stretch of
+     *  transliteration corresponding to a Tibetan wowel (without any
+     *  [achen or other] consonant) */
+    boolean isWowel(String s);
+
+    /** Returns true if and only if the pair given has a simple error
+     *  other than being a mere disambiguator. */
+    boolean hasSimpleError(TPair p);
+}