automaton initial state is always 0

lucene/analysis/common/src/java/org/apache/lucene/analysis/hunspell/Stemmer.java

@@ -474,7 +474,7 @@ final class Stemmer {
   private boolean checkCondition(int condition, char c1[], int c1off, int c1len, char c2[], int c2off, int c2len) {
     if (condition != 0) {
       CharacterRunAutomaton pattern = dictionary.patterns.get(condition);
-      int state = pattern.getInitialState();
+      int state = 0;
       for (int i = c1off; i < c1off + c1len; i++) {
         state = pattern.step(state, c1[i]);
         if (state == -1) {

lucene/codecs/src/java/org/apache/lucene/codecs/blocktreeords/OrdsIntersectTermsEnum.java

@@ -92,7 +92,7 @@ final class OrdsIntersectTermsEnum extends TermsEnum {
     final OrdsIntersectTermsEnumFrame f = stack[0];
     f.fp = f.fpOrig = fr.rootBlockFP;
     f.prefix = 0;
-    f.setState(runAutomaton.getInitialState());
+    f.setState(0);
     f.arc = arc;
     f.outputPrefix = arc.output;
     f.load(fr.rootCode);

lucene/codecs/src/java/org/apache/lucene/codecs/memory/DirectPostingsFormat.java

@@ -969,7 +969,7 @@ public final class DirectPostingsFormat extends PostingsFormat {
         states = new State[1];
         states[0] = new State();
         states[0].changeOrd = terms.length;
-        states[0].state = runAutomaton.getInitialState();
+        states[0].state = 0;
         states[0].transitionCount = compiledAutomaton.automaton.getNumTransitions(states[0].state);
         compiledAutomaton.automaton.initTransition(states[0].state, states[0].transition);
         states[0].transitionUpto = -1;

lucene/codecs/src/java/org/apache/lucene/codecs/memory/FSTOrdTermsReader.java

@@ -705,7 +705,7 @@ public class FSTOrdTermsReader extends FieldsProducer {
       /** Load frame for start arc(node) on fst */
       Frame loadFirstFrame(Frame frame) throws IOException {
         frame.arc = fst.getFirstArc(frame.arc);
-        frame.state = fsa.getInitialState();
+        frame.state = 0;
         return frame;
       }
 

lucene/codecs/src/java/org/apache/lucene/codecs/memory/FSTTermsReader.java

@@ -602,7 +602,7 @@ public class FSTTermsReader extends FieldsProducer {
       /** Load frame for start arc(node) on fst */
       Frame loadFirstFrame(Frame frame) throws IOException {
         frame.fstArc = fst.getFirstArc(frame.fstArc);
-        frame.fsaState = fsa.getInitialState();
+        frame.fsaState = 0;
         return frame;
       }
 

lucene/core/src/java/org/apache/lucene/codecs/blocktree/IntersectTermsEnum.java

@@ -124,7 +124,7 @@ final class IntersectTermsEnum extends TermsEnum {
     final IntersectTermsEnumFrame f = stack[0];
     f.fp = f.fpOrig = fr.rootBlockFP;
     f.prefix = 0;
-    f.setState(runAutomaton.getInitialState());
+    f.setState(0);
     f.arc = arc;
     f.outputPrefix = arc.output;
     f.load(fr.rootCode);

lucene/core/src/java/org/apache/lucene/index/AutomatonTermsEnum.java

@@ -110,7 +110,7 @@ public class AutomatonTermsEnum extends FilteredTermsEnum {
     if (term == null) {
       assert seekBytesRef.length() == 0;
       // return the empty term, as it's valid
-      if (runAutomaton.isAccept(runAutomaton.getInitialState())) {   
+      if (runAutomaton.isAccept(0)) {   
         return seekBytesRef.get();
       }
     } else {
@@ -135,7 +135,7 @@ public class AutomatonTermsEnum extends FilteredTermsEnum {
   private void setLinear(int position) {
     assert linear == false;
     
-    int state = runAutomaton.getInitialState();
+    int state = 0;
     assert state == 0;
     int maxInterval = 0xff;
     //System.out.println("setLinear pos=" + position + " seekbytesRef=" + seekBytesRef);
@@ -182,7 +182,7 @@ public class AutomatonTermsEnum extends FilteredTermsEnum {
     int state;
     int pos = 0;
     savedStates.grow(seekBytesRef.length()+1);
-    savedStates.setIntAt(0, runAutomaton.getInitialState());
+    savedStates.setIntAt(0, 0);
     
     while (true) {
       curGen++;

lucene/core/src/java/org/apache/lucene/util/automaton/ByteRunAutomaton.java

@@ -36,7 +36,7 @@ public class ByteRunAutomaton extends RunAutomaton {
    * Returns true if the given byte array is accepted by this automaton
    */
   public boolean run(byte[] s, int offset, int length) {
-    int p = initial;
+    int p = 0;
     int l = offset + length;
     for (int i = offset; i < l; i++) {
       p = step(p, s[i] & 0xFF);

lucene/core/src/java/org/apache/lucene/util/automaton/CharacterRunAutomaton.java

@@ -43,7 +43,7 @@ public class CharacterRunAutomaton extends RunAutomaton {
    * Returns true if the given string is accepted by this automaton.
    */
   public boolean run(String s) {
-    int p = initial;
+    int p = 0;
     int l = s.length();
     for (int i = 0, cp = 0; i < l; i += Character.charCount(cp)) {
       p = step(p, cp = s.codePointAt(i));
@@ -56,7 +56,7 @@ public class CharacterRunAutomaton extends RunAutomaton {
    * Returns true if the given string is accepted by this automaton
    */
   public boolean run(char[] s, int offset, int length) {
-    int p = initial;
+    int p = 0;
     int l = offset + length;
     for (int i = offset, cp = 0; i < l; i += Character.charCount(cp)) {
       p = step(p, cp = Character.codePointAt(s, i, l));

lucene/core/src/java/org/apache/lucene/util/automaton/CompiledAutomaton.java

@@ -351,7 +351,7 @@ public class CompiledAutomaton {
 
     //if (DEBUG) System.out.println("CA.floor input=" + input.utf8ToString());
 
-    int state = runAutomaton.getInitialState();
+    int state = 0;
 
     // Special case empty string:
     if (input.length == 0) {

lucene/core/src/java/org/apache/lucene/util/automaton/RunAutomaton.java

@@ -32,7 +32,7 @@ package org.apache.lucene.util.automaton;
 import java.util.Arrays;
 
 /**
- * Finite-state automaton with fast run operation.
+ * Finite-state automaton with fast run operation.  The initial state is always 0.
  * 
  * @lucene.experimental
  */
@@ -41,7 +41,6 @@ public abstract class RunAutomaton {
   final int maxInterval;
   final int size;
   final boolean[] accept;
-  final int initial;
   final int[] transitions; // delta(state,c) = transitions[state*points.length +
                      // getCharClass(c)]
   final int[] points; // char interval start points
@@ -53,7 +52,7 @@ public abstract class RunAutomaton {
   @Override
   public String toString() {
     StringBuilder b = new StringBuilder();
-    b.append("initial state: ").append(initial).append("\n");
+    b.append("initial state: 0\n");
     for (int i = 0; i < size; i++) {
       b.append("state " + i);
       if (accept[i]) b.append(" [accept]:\n");
@@ -92,13 +91,6 @@ public abstract class RunAutomaton {
     return accept[state];
   }
   
-  /**
-   * Returns initial state.
-   */
-  public final int getInitialState() {
-    return initial;
-  }
-  
   /**
    * Returns array of codepoint class interval start points. The array should
    * not be modified by the caller.
@@ -138,7 +130,6 @@ public abstract class RunAutomaton {
     a = Operations.determinize(a, maxDeterminizedStates);
     this.automaton = a;
     points = a.getStartPoints();
-    initial = 0;
     size = Math.max(1,a.getNumStates());
     accept = new boolean[size];
     transitions = new int[size * points.length];
@@ -188,7 +179,6 @@ public abstract class RunAutomaton {
   public int hashCode() {
     final int prime = 31;
     int result = 1;
-    result = prime * result + initial;
     result = prime * result + maxInterval;
     result = prime * result + points.length;
     result = prime * result + size;
@@ -201,7 +191,6 @@ public abstract class RunAutomaton {
     if (obj == null) return false;
     if (getClass() != obj.getClass()) return false;
     RunAutomaton other = (RunAutomaton) obj;
-    if (initial != other.initial) return false;
     if (maxInterval != other.maxInterval) return false;
     if (size != other.size) return false;
     if (!Arrays.equals(points, other.points)) return false;

lucene/core/src/test/org/apache/lucene/index/TestTermsEnum.java

@@ -170,7 +170,7 @@ public class TestTermsEnum extends LuceneTestCase {
   }
 
   private boolean accepts(CompiledAutomaton c, BytesRef b) {
-    int state = c.runAutomaton.getInitialState();
+    int state = 0;
     for(int idx=0;idx<b.length;idx++) {
       assertTrue(state != -1);
       state = c.runAutomaton.step(state, b.bytes[b.offset+idx] & 0xff);
@@ -291,7 +291,7 @@ public class TestTermsEnum extends LuceneTestCase {
           System.out.println("\nTEST: iter2=" + iter2 + " startTerm=" + (startTerm == null ? "<null>" : startTerm.utf8ToString()));
 
           if (startTerm != null) {
-            int state = c.runAutomaton.getInitialState();
+            int state = 0;
             for(int idx=0;idx<startTerm.length;idx++) {
               final int label = startTerm.bytes[startTerm.offset+idx] & 0xff;
               System.out.println("  state=" + state + " label=" + label);

lucene/core/src/test/org/apache/lucene/util/automaton/TestUTF32ToUTF8.java

@@ -166,12 +166,12 @@ public class TestUTF32ToUTF8 extends LuceneTestCase {
     CharacterRunAutomaton cra = new CharacterRunAutomaton(automaton);
     ByteRunAutomaton bra = new ByteRunAutomaton(automaton);
     // make sure character dfa accepts empty string
-    assertTrue(cra.isAccept(cra.getInitialState()));
+    assertTrue(cra.isAccept(0));
     assertTrue(cra.run(""));
     assertTrue(cra.run(new char[0], 0, 0));
 
     // make sure byte dfa accepts empty string
-    assertTrue(bra.isAccept(bra.getInitialState()));
+    assertTrue(bra.isAccept(0));
     assertTrue(bra.run(new byte[0], 0, 0));
   }
   

lucene/test-framework/src/java/org/apache/lucene/analysis/MockTokenizer.java

@@ -92,7 +92,7 @@ public class MockTokenizer extends Tokenizer {
     super(factory);
     this.runAutomaton = runAutomaton;
     this.lowerCase = lowerCase;
-    this.state = runAutomaton.getInitialState();
+    this.state = 0;
     this.maxTokenLength = maxTokenLength;
   }
 
@@ -252,7 +252,7 @@ public class MockTokenizer extends Tokenizer {
 
   protected boolean isTokenChar(int c) {
     if (state < 0) {
-      state = runAutomaton.getInitialState();
+      state = 0;
     }
     state = runAutomaton.step(state, c);
     if (state < 0) {
@@ -270,7 +270,7 @@ public class MockTokenizer extends Tokenizer {
   public void reset() throws IOException {
     try {
       super.reset();
-      state = runAutomaton.getInitialState();
+      state = 0;
       lastOffset = off = 0;
       bufferedCodePoint = -1;
       if (streamState == State.RESET) {