ADD: nodes, get-put visitors, abstracting BitSequence

Signed-off-by: Thomas Zamojski <thomas.zamojski@quadratic-labs.com>

Author: thomas-quadratic

src/main/java/org/hyperledger/besu/ethereum/stateless/bintrie/BitSequence.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright Hyperledger Besu Contributors
+ *
+ * Licensed 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ */
+package org.hyperledger.besu.ethereum.stateless.bintrie;
+
+public interface BitSequenceFactory<K extends BitSequence<K>> {
+  /**
+   * Default empty Sequence.
+   *
+   * @return Empty BitSequence.
+   */
+  public K empty();
+
+  /**
+   * Get a BitSequence from a binary string representation.
+   *
+   * @param bits Binary string representation.
+   * @return A string representation of the node.
+   */
+  public K fromBinaryString(String bits);
+
+  /**
+   * Get a BitSequence from an Integer.
+   *
+   * @param value Integer value.
+   * @return BitSequence representing value in big-endian format.
+   */
+  public K fromInteger(int value);
+
+  /**
+   * Decode a BitSequence from the encoded form.
+   *
+   * @param encoded The encoded representation of a BytesPackedBitSequence
+   * @return Decoded BitSequence.
+   */
+  public K decode(byte[] encoded);
+}