From 023c253c932da76d82864403f6c1cc1a92c83f00 Mon Sep 17 00:00:00 2001
From: robert-bor <bor.robert@gmail.com>
Date: Tue, 22 Sep 2015 20:14:48 +0200
Subject: [PATCH] Issue #16 #20 #21 adopted pull request from remen which makes
 sure the failure states are constructed as part of the trie construction.
 This prevents the NPE which the referenced issues are complaining about.

---
 src/main/java/org/ahocorasick/trie/Trie.java  | 11 +++---
 .../java/org/ahocorasick/trie/TrieTest.java   | 36 ++++++++++---------
 2 files changed, 26 insertions(+), 21 deletions(-)

diff --git a/src/main/java/org/ahocorasick/trie/Trie.java b/src/main/java/org/ahocorasick/trie/Trie.java
index 3fa533d..0301e19 100644
--- a/src/main/java/org/ahocorasick/trie/Trie.java
+++ b/src/main/java/org/ahocorasick/trie/Trie.java
@@ -40,7 +40,7 @@ public class Trie {
 
     public Collection<Token> tokenize(String text) {
 
-        Collection<Token> tokens = new ArrayList<Token>();
+        Collection<Token> tokens = new ArrayList<>();
 
         Collection<Emit> collectedEmits = parseText(text);
         int lastCollectedPosition = -1;
@@ -86,8 +86,6 @@ public class Trie {
     }
 
     public void parseText(CharSequence text, EmitHandler emitHandler) {
-        checkForConstructedFailureStates();
-
         State currentState = this.rootState;
         for (int position = 0; position < text.length(); position++) {
             Character character = text.charAt(position);
@@ -130,7 +128,7 @@ public class Trie {
     }
 
     private void constructFailureStates() {
-        Queue<State> queue = new LinkedBlockingDeque<State>();
+        Queue<State> queue = new LinkedBlockingDeque<>();
 
         // First, set the fail state of all depth 1 states to the root state
         for (State depthOneState : this.rootState.getStates()) {
@@ -201,6 +199,11 @@ public class Trie {
             return this;
         }
 
+        public TrieBuilder stopOnHit() {
+            trie.trieConfig.setStopOnHit(true);
+            return this;
+        }
+
         public Trie build() {
             trie.constructFailureStates();
             return trie;
diff --git a/src/test/java/org/ahocorasick/trie/TrieTest.java b/src/test/java/org/ahocorasick/trie/TrieTest.java
index 5665059..8bd4593 100644
--- a/src/test/java/org/ahocorasick/trie/TrieTest.java
+++ b/src/test/java/org/ahocorasick/trie/TrieTest.java
@@ -46,12 +46,13 @@ public class TrieTest {
 
     @Test
     public void ushersTestAndStopOnHit() {
-        Trie trie = new Trie();
-        trie.addKeyword("hers");
-        trie.addKeyword("his");
-        trie.addKeyword("she");
-        trie.addKeyword("he");
-        trie.stopOnHit();
+        Trie trie = Trie.builder()
+                .addKeyword("hers")
+                .addKeyword("his")
+                .addKeyword("she")
+                .addKeyword("he")
+                .stopOnHit()
+                .build();
         Collection<Emit> emits = trie.parseText("ushers");
         assertEquals(2, emits.size()); // she @ 3, he @ 3, hers @ 5
         Iterator<Emit> iterator = emits.iterator();
@@ -62,11 +63,11 @@ public class TrieTest {
     @Test
     public void ushersTest() {
         Trie trie = Trie.builder()
-            .addKeyword("hers")
-            .addKeyword("his")
-            .addKeyword("she")
-            .addKeyword("he")
-            .build();
+                .addKeyword("hers")
+                .addKeyword("his")
+                .addKeyword("she")
+                .addKeyword("he")
+                .build();
         Collection<Emit> emits = trie.parseText("ushers");
         assertEquals(3, emits.size()); // she @ 3, he @ 3, hers @ 5
         Iterator<Emit> iterator = emits.iterator();
@@ -77,11 +78,12 @@ public class TrieTest {
 
     @Test
     public void ushersTestByCallback() {
-        Trie trie = new Trie();
-        trie.addKeyword("hers");
-        trie.addKeyword("his");
-        trie.addKeyword("she");
-        trie.addKeyword("he");
+        Trie trie = Trie.builder()
+                .addKeyword("hers")
+                .addKeyword("his")
+                .addKeyword("she")
+                .addKeyword("he")
+                .build();
 
         final List<Emit> emits = new ArrayList<>();
         EmitHandler emitHandler = new EmitHandler() {
@@ -262,7 +264,7 @@ public class TrieTest {
     @Test
     public void unicodeIssueBug8ReportedByDwyerk() {
         String target = "LİKE THIS"; // The second character ('İ') is Unicode, which was read by AC as a 2-byte char
-        assertEquals("THIS", target.substring(5,9)); // Java does it the right way
+        assertEquals("THIS", target.substring(5, 9)); // Java does it the right way
         Trie trie = Trie.builder().caseInsensitive().onlyWholeWords()
             .addKeyword("this")
             .build();