From 4be3e115b6e36b8750d1b90f224017d8ce9a6272 Mon Sep 17 00:00:00 2001
From: Douglas Lovell <doug.lovell@roguewave.com>
Date: Wed, 28 Oct 2015 14:10:53 -0600
Subject: [PATCH] add builder method for setting word transitions

---
 src/main/java/org/ahocorasick/trie/Trie.java | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/src/main/java/org/ahocorasick/trie/Trie.java b/src/main/java/org/ahocorasick/trie/Trie.java
index deed616..c8956d4 100644
--- a/src/main/java/org/ahocorasick/trie/Trie.java
+++ b/src/main/java/org/ahocorasick/trie/Trie.java
@@ -222,6 +222,8 @@ public class Trie {
         private final TrieConfig trieConfig = new TrieConfig();
 
         private final Trie trie = new Trie(trieConfig);
+        
+        private boolean hasAddedKeyword = false;
 
         private TrieBuilder() {}
 
@@ -240,11 +242,21 @@ public class Trie {
             return this;
         }
 
-        public TrieBuilder addKeyword(String keyword) {
-            trie.addKeyword(keyword);
+        public TrieBuilder wordTransitions() {
+            if (hasAddedKeyword) {
+                throw new IllegalStateException(
+                    "Unable to switch to word transitions after keywords added");
+            }
+            this.trieConfig.setWordTransitions(true);
             return this;
         }
 
+        public TrieBuilder addKeyword(String keyword) {
+            trie.addKeyword(keyword);
+            hasAddedKeyword = true;
+            return this;
+        }
+        
         public Trie build() {
             trie.constructFailureStates();
             return trie;