content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you under the Apache License, Version 2.0 (the
   * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.apache.cassandra.db.tries;
  
  import java.util.function.Function;
  
  import org.agrona.DirectBuffer;
  
  /**
   * Simple utility class for dumping the structure of a trie to string.
   */
  class TrieDumper<T> implements Trie.Walker<T, String>
  {
      private final StringBuilder b;
      private final Function<T, String> contentToString;
      int needsIndent = -1;
      int currentLength = 0;
  
      public TrieDumper(Function<T, String> contentToString)
      {
          this.contentToString = contentToString;
          this.b = new StringBuilder();
      }
  
      private void endLineAndSetIndent(int newIndent)
      {
          needsIndent = newIndent;
      }
  
      @Override
      public void resetPathLength(int newLength)
      {
          currentLength = newLength;
          endLineAndSetIndent(newLength);
      }
  
      private void maybeIndent()
      {
          if (needsIndent >= 0)
          {
              b.append('\n');
              for (int i = 0; i < needsIndent; ++i)
                  b.append("  ");
              needsIndent = -1;
          }
      }
  
      @Override
      public void addPathByte(int nextByte)
      {
          maybeIndent();
          ++currentLength;
          b.append(String.format("%02x", nextByte));
      }
  
      @Override
      public void addPathBytes(DirectBuffer buffer, int pos, int count)
      {
          maybeIndent();
          for (int i = 0; i < count; ++i)
              b.append(String.format("%02x", buffer.getByte(pos + i) & 0xFF));
          currentLength += count;
      }
  
      @Override
      public void content(T content)
      {
          b.append(" -> ");
          b.append(contentToString.apply(content));
          endLineAndSetIndent(currentLength);
      }
  
      @Override
      public String complete()
      {
          return b.toString();
      }
  }
  