How to use

getArc

method

in

org.apache.lucene.util.fst.FSTEnum

/** Rewinds enum state to match the shared prefix between
 *  current term and target term */
protected final void rewindPrefix() throws IOException {
 if (upto == 0) {
  //System.out.println("  init");
  upto = 1;
  fst.readFirstTargetArc(getArc(0), getArc(1), fstReader);
  return;
 }
 //System.out.println("  rewind upto=" + upto + " vs targetLength=" + targetLength);
 final int currentLimit = upto;
 upto = 1;
 while (upto < currentLimit && upto <= targetLength+1) {
  final int cmp = getCurrentLabel() - getTargetLabel();
  if (cmp < 0) {
   // seek forward
   //System.out.println("    seek fwd");
   break;
  } else if (cmp > 0) {
   // seek backwards -- reset this arc to the first arc
   final FST.Arc<T> arc = getArc(upto);
   fst.readFirstTargetArc(getArc(upto-1), arc, fstReader);
   //System.out.println("    seek first arc");
   break;
  }
  upto++;
 }
 //System.out.println("  fall through upto=" + upto);
}

protected void doNext() throws IOException {
 //System.out.println("FE: next upto=" + upto);
 if (upto == 0) {
  //System.out.println("  init");
  upto = 1;
  fst.readFirstTargetArc(getArc(0), getArc(1), fstReader);
 } else {
  // pop
  //System.out.println("  check pop curArc target=" + arcs[upto].target + " label=" + arcs[upto].label + " isLast?=" + arcs[upto].isLast());
  while (arcs[upto].isLast()) {
   upto--;
   if (upto == 0) {
    //System.out.println("  eof");
    return;
   }
  }
  fst.readNextArc(arcs[upto], fstReader);
 }
 pushFirst();
}

/** doFloor controls the behavior of advance: if it's true
 *  doFloor is true, advance positions to the biggest
 *  term before target.  */
protected FSTEnum(FST<T> fst) {
 this.fst = fst;
 fstReader = fst.getBytesReader();
 NO_OUTPUT = fst.outputs.getNoOutput();
 fst.getFirstArc(getArc(0));
 output[0] = NO_OUTPUT;
}

private void pushLast() throws IOException {
 FST.Arc<T> arc = arcs[upto];
 assert arc != null;
 while (true) {
  setCurrentLabel(arc.label);
  output[upto] = fst.outputs.add(output[upto-1], arc.output);
  if (arc.label == FST.END_LABEL) {
   // Final node
   break;
  }
  incr();
  arc = fst.readLastTargetArc(arc, getArc(upto), fstReader);
 }
}

private void pushFirst() throws IOException {
 FST.Arc<T> arc = arcs[upto];
 assert arc != null;
 while (true) {
  output[upto] = fst.outputs.add(output[upto-1], arc.output);
  if (arc.label == FST.END_LABEL) {
   // Final node
   break;
  }
  //System.out.println("  pushFirst label=" + (char) arc.label + " upto=" + upto + " output=" + fst.outputs.outputToString(output[upto]));
  setCurrentLabel(arc.label);
  incr();
  
  final FST.Arc<T> nextArc = getArc(upto);
  fst.readFirstTargetArc(arc, nextArc, fstReader);
  arc = nextArc;
 }
}

FST.Arc<T> arc = getArc(upto-1);
int targetLabel = getTargetLabel();
 final FST.Arc<T> nextArc = fst.findTargetArc(targetLabel, arc, getArc(upto), fstReader);
 if (nextArc == null) {
  fst.readFirstTargetArc(arc, getArc(upto), fstReader);

FST.Arc<T> arc = getArc(upto);
int targetLabel = getTargetLabel();
   arc = fst.readFirstTargetArc(arc, getArc(upto), fstReader);
   targetLabel = getTargetLabel();
   continue;
    fst.readFirstTargetArc(getArc(upto-1), arc, fstReader);
    if (arc.label < targetLabel) {
    arc = getArc(upto);
   arc = fst.readFirstTargetArc(arc, getArc(upto), fstReader);
   targetLabel = getTargetLabel();
  } else if (arc.label > targetLabel) {
    fst.readFirstTargetArc(getArc(upto-1), arc, fstReader);
    if (arc.label < targetLabel) {
    arc = getArc(upto);

FST.Arc<T> arc = getArc(upto);
int targetLabel = getTargetLabel();
   arc = fst.readFirstTargetArc(arc, getArc(upto), fstReader);
   targetLabel = getTargetLabel();
   continue;
     return;
    final FST.Arc<T> prevArc = getArc(upto);
   arc = fst.readFirstTargetArc(arc, getArc(upto), fstReader);
   targetLabel = getTargetLabel();
  } else if (arc.label > targetLabel) {
     return;
    final FST.Arc<T> prevArc = getArc(upto);

protected void doNext() throws IOException {
 //System.out.println("FE: next upto=" + upto);
 if (upto == 0) {
  //System.out.println("  init");
  upto = 1;
  fst.readFirstTargetArc(getArc(0), getArc(1), fstReader);
 } else {
  // pop
  //System.out.println("  check pop curArc target=" + arcs[upto].target + " label=" + arcs[upto].label + " isLast?=" + arcs[upto].isLast());
  while (arcs[upto].isLast()) {
   upto--;
   if (upto == 0) {
    //System.out.println("  eof");
    return;
   }
  }
  fst.readNextArc(arcs[upto], fstReader);
 }
 pushFirst();
}

protected void doNext() throws IOException {
 //System.out.println("FE: next upto=" + upto);
 if (upto == 0) {
  //System.out.println("  init");
  upto = 1;
  fst.readFirstTargetArc(getArc(0), getArc(1), fstReader);
 } else {
  // pop
  //System.out.println("  check pop curArc target=" + arcs[upto].target + " label=" + arcs[upto].label + " isLast?=" + arcs[upto].isLast());
  while (arcs[upto].isLast()) {
   upto--;
   if (upto == 0) {
    //System.out.println("  eof");
    return;
   }
  }
  fst.readNextArc(arcs[upto], fstReader);
 }
 pushFirst();
}

protected void doNext() throws IOException {
 //System.out.println("FE: next upto=" + upto);
 if (upto == 0) {
  //System.out.println("  init");
  upto = 1;
  fst.readFirstTargetArc(getArc(0), getArc(1), fstReader);
 } else {
  // pop
  //System.out.println("  check pop curArc target=" + arcs[upto].target + " label=" + arcs[upto].label + " isLast?=" + arcs[upto].isLast());
  while (arcs[upto].isLast()) {
   upto--;
   if (upto == 0) {
    //System.out.println("  eof");
    return;
   }
  }
  fst.readNextArc(arcs[upto], fstReader);
 }
 pushFirst();
}

/** doFloor controls the behavior of advance: if it's true
 *  doFloor is true, advance positions to the biggest
 *  term before target.  */
protected FSTEnum(FST<T> fst) {
 this.fst = fst;
 fstReader = fst.getBytesReader();
 NO_OUTPUT = fst.outputs.getNoOutput();
 fst.getFirstArc(getArc(0));
 output[0] = NO_OUTPUT;
}

/** doFloor controls the behavior of advance: if it's true
 *  doFloor is true, advance positions to the biggest
 *  term before target.  */
protected FSTEnum(FST<T> fst) {
 this.fst = fst;
 fstReader = fst.getBytesReader();
 NO_OUTPUT = fst.outputs.getNoOutput();
 fst.getFirstArc(getArc(0));
 output[0] = NO_OUTPUT;
}

/** doFloor controls the behavior of advance: if it's true
 *  doFloor is true, advance positions to the biggest
 *  term before target.  */
protected FSTEnum(FST<T> fst) {
 this.fst = fst;
 fstReader = fst.getBytesReader();
 NO_OUTPUT = fst.outputs.getNoOutput();
 fst.getFirstArc(getArc(0));
 output[0] = NO_OUTPUT;
}

private void pushLast() throws IOException {
 FST.Arc<T> arc = arcs[upto];
 assert arc != null;
 while (true) {
  setCurrentLabel(arc.label);
  output[upto] = fst.outputs.add(output[upto-1], arc.output);
  if (arc.label == FST.END_LABEL) {
   // Final node
   break;
  }
  incr();
  arc = fst.readLastTargetArc(arc, getArc(upto), fstReader);
 }
}

private void pushLast() throws IOException {
 FST.Arc<T> arc = arcs[upto];
 assert arc != null;
 while (true) {
  setCurrentLabel(arc.label);
  output[upto] = fst.outputs.add(output[upto-1], arc.output);
  if (arc.label == FST.END_LABEL) {
   // Final node
   break;
  }
  incr();
  arc = fst.readLastTargetArc(arc, getArc(upto), fstReader);
 }
}

private void pushLast() throws IOException {
 FST.Arc<T> arc = arcs[upto];
 assert arc != null;
 while (true) {
  setCurrentLabel(arc.label);
  output[upto] = fst.outputs.add(output[upto-1], arc.output);
  if (arc.label == FST.END_LABEL) {
   // Final node
   break;
  }
  incr();
  arc = fst.readLastTargetArc(arc, getArc(upto), fstReader);
 }
}

private void pushFirst() throws IOException {
 FST.Arc<T> arc = arcs[upto];
 assert arc != null;
 while (true) {
  output[upto] = fst.outputs.add(output[upto-1], arc.output);
  if (arc.label == FST.END_LABEL) {
   // Final node
   break;
  }
  //System.out.println("  pushFirst label=" + (char) arc.label + " upto=" + upto + " output=" + fst.outputs.outputToString(output[upto]));
  setCurrentLabel(arc.label);
  incr();
  
  final FST.Arc<T> nextArc = getArc(upto);
  fst.readFirstTargetArc(arc, nextArc, fstReader);
  arc = nextArc;
 }
}

private void pushFirst() throws IOException {
 FST.Arc<T> arc = arcs[upto];
 assert arc != null;
 while (true) {
  output[upto] = fst.outputs.add(output[upto-1], arc.output);
  if (arc.label == FST.END_LABEL) {
   // Final node
   break;
  }
  //System.out.println("  pushFirst label=" + (char) arc.label + " upto=" + upto + " output=" + fst.outputs.outputToString(output[upto]));
  setCurrentLabel(arc.label);
  incr();
  
  final FST.Arc<T> nextArc = getArc(upto);
  fst.readFirstTargetArc(arc, nextArc, fstReader);
  arc = nextArc;
 }
}

private void pushFirst() throws IOException {
 FST.Arc<T> arc = arcs[upto];
 assert arc != null;
 while (true) {
  output[upto] = fst.outputs.add(output[upto-1], arc.output);
  if (arc.label == FST.END_LABEL) {
   // Final node
   break;
  }
  //System.out.println("  pushFirst label=" + (char) arc.label + " upto=" + upto + " output=" + fst.outputs.outputToString(output[upto]));
  setCurrentLabel(arc.label);
  incr();
  
  final FST.Arc<T> nextArc = getArc(upto);
  fst.readFirstTargetArc(arc, nextArc, fstReader);
  arc = nextArc;
 }
}