private Constant parseConstant() throws IOException {
    int constValueIndex = input.readUnsignedShort();
    Constant value = pool.get(constValueIndex);

    if (observer != null) {
      String human =
          (value instanceof CstString) ? ((CstString) value).toQuoted() : value.toHuman();
      parsed(2, "constant_value: " + human);
    }

    return value;
  }
Helper for {@link #parseValue}, which parses a constant reference and returns the referred-to
constant value.

@return {@code non-null;} the parsed value
android/android_framework/dex-maker/src/main/java/com/android/dx/cf/direct/AnnotationParser.java