content: /*
   * Copyright (C) 2007 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.android.dx.dex.file;
  
  import com.taobao.android.dx.rop.cst.Constant;
  import com.taobao.android.dx.rop.cst.CstFieldRef;
  import com.taobao.android.dx.util.AnnotatedOutput;
  import com.taobao.android.dx.util.Hex;
  
  import java.util.Collection;
  import java.util.TreeMap;
  
  /**
   * Field refs list section of a {@code .dex} file.
   */
  public final class FieldIdsSection extends MemberIdsSection {
      /**
       * {@code non-null;} map from field constants to {@link
       * FieldIdItem} instances
       */
      private final TreeMap<CstFieldRef, FieldIdItem> fieldIds;
  
      /**
       * Constructs an instance. The file offset is initially unknown.
       *
       * @param file {@code non-null;} file that this instance is part of
       */
      public FieldIdsSection(DexFile file) {
          super("field_ids", file);
  
          fieldIds = new TreeMap<CstFieldRef, FieldIdItem>();
      }
  
      /** {@inheritDoc} */
      @Override
      public Collection<? extends Item> items() {
          return fieldIds.values();
      }
  
      /** {@inheritDoc} */
      @Override
      public IndexedItem get(Constant cst) {
          if (cst == null) {
              throw new NullPointerException("cst == null");
          }
  
          throwIfNotPrepared();
  
          IndexedItem result = fieldIds.get((CstFieldRef) cst);
  
          if (result == null) {
              throw new IllegalArgumentException("not found");
          }
  
          return result;
      }
  
      /**
       * Writes the portion of the file header that refers to this instance.
       *
       * @param out {@code non-null;} where to write
       */
      public void writeHeaderPart(AnnotatedOutput out) {
          throwIfNotPrepared();
  
          int sz = fieldIds.size();
          int offset = (sz == 0) ? 0 : getFileOffset();
  
          if (out.annotates()) {
              out.annotate(4, "field_ids_size:  " + Hex.u4(sz));
              out.annotate(4, "field_ids_off:   " + Hex.u4(offset));
          }
  
          out.writeInt(sz);
          out.writeInt(offset);
      }
  
      /**
       * Interns an element into this instance.
       *
       * @param field {@code non-null;} the reference to intern
       * @return {@code non-null;} the interned reference
       */
      public synchronized FieldIdItem intern(CstFieldRef field) {
          if (field == null) {
              throw new NullPointerException("field == null");
          }
  
          throwIfPrepared();
  
          FieldIdItem result = fieldIds.get(field);
  
          if (result == null) {
              result = new FieldIdItem(field);
              fieldIds.put(field, result);
          }
  
          return result;
      }
  
      /**
       * Gets the index of the given reference, which must have been added
       * to this instance.
       *
       * @param ref {@code non-null;} the reference to look up
       * @return {@code >= 0;} the reference's index
       */
      public int indexOf(CstFieldRef ref) {
          if (ref == null) {
              throw new NullPointerException("ref == null");
          }
  
          throwIfNotPrepared();
  
          FieldIdItem item = fieldIds.get(ref);
  
          if (item == null) {
              throw new IllegalArgumentException("not found");
          }
  
          return item.getIndex();
      }
  }
  