content: /*
   * Copyright (C) 2011 The Android Open Source Project
   *
   * 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.
   */
  
  package com.taobao.atlas.dexmerge.dx.io.instructions;
  
  /**
   * Base implementation of {@link CodeCursor}.
   */
  public abstract class BaseCodeCursor implements CodeCursor {
      /** base address map */
      private final AddressMap baseAddressMap;
  
      /** next index within {@link #array} to read from or write to */
      private int cursor;
  
      /**
       * Constructs an instance.
       */
      public BaseCodeCursor() {
          this.baseAddressMap = new AddressMap();
          this.cursor = 0;
      }
  
      /** @inheritDoc */
      public final int cursor() {
          return cursor;
      }
  
      /** @inheritDoc */
      public final int baseAddressForCursor() {
          int mapped = baseAddressMap.get(cursor);
          return (mapped >= 0) ? mapped : cursor;
      }
  
      /** @inheritDoc */
      public final void setBaseAddress(int targetAddress, int baseAddress) {
          baseAddressMap.put(targetAddress, baseAddress);
      }
  
      /**
       * Advance the cursor by the indicated amount.
       */
      protected final void advance(int amount) {
          cursor += amount;
      }
  }
  