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.cql3.selection;
  
  import java.io.IOException;
  import java.nio.ByteBuffer;
  import java.util.List;
  
  import com.google.common.base.Objects;
  
  import org.apache.cassandra.cql3.ColumnSpecification;
  import org.apache.cassandra.cql3.QueryOptions;
  import org.apache.cassandra.db.TypeSizes;
  import org.apache.cassandra.db.filter.ColumnFilter;
  import org.apache.cassandra.db.marshal.AbstractType;
  import org.apache.cassandra.db.marshal.UserType;
  import org.apache.cassandra.exceptions.InvalidRequestException;
  import org.apache.cassandra.io.util.DataInputPlus;
  import org.apache.cassandra.io.util.DataOutputPlus;
  import org.apache.cassandra.schema.TableMetadata;
  import org.apache.cassandra.transport.ProtocolVersion;
  
  final class FieldSelector extends Selector
  {
      protected static final SelectorDeserializer deserializer = new SelectorDeserializer()
      {
          protected Selector deserialize(DataInputPlus in, int version, TableMetadata metadata) throws IOException
          {
              UserType type = (UserType) readType(metadata, in);
              int field = in.readUnsignedVInt32();
              Selector selected = Selector.serializer.deserialize(in, version, metadata);
  
              return new FieldSelector(type, field, selected);
          }
      };
  
      private final UserType type;
      private final int field;
      private final Selector selected;
  
      public static Factory newFactory(final UserType type, final int field, final Selector.Factory factory)
      {
          return new Factory()
          {
              protected String getColumnName()
              {
                  return String.format("%s.%s", factory.getColumnName(), type.fieldName(field));
              }
  
              protected AbstractType<?> getReturnType()
              {
                  return type.fieldType(field);
              }
  
              protected void addColumnMapping(SelectionColumnMapping mapping, ColumnSpecification resultsColumn)
              {
                  factory.addColumnMapping(mapping, resultsColumn);
              }
  
              public Selector newInstance(QueryOptions options) throws InvalidRequestException
              {
                  return new FieldSelector(type, field, factory.newInstance(options));
              }
  
              public boolean isAggregateSelectorFactory()
              {
                  return factory.isAggregateSelectorFactory();
              }
  
              public boolean areAllFetchedColumnsKnown()
              {
                  return factory.areAllFetchedColumnsKnown();
              }
  
              public void addFetchedColumns(ColumnFilter.Builder builder)
              {
                  factory.addFetchedColumns(builder);
              }
          };
      }
  
      public void addFetchedColumns(ColumnFilter.Builder builder)
      {
          selected.addFetchedColumns(builder);
      }
  
      public void addInput(InputRow input)
      {
          selected.addInput(input);
      }
  
      public ByteBuffer getOutput(ProtocolVersion protocolVersion)
      {
          ByteBuffer value = selected.getOutput(protocolVersion);
          if (value == null)
              return null;
          List<ByteBuffer> buffers = type.unpack(value);
          return field < buffers.size() ? buffers.get(field) : null;
      }
  
      @Override
      protected ColumnTimestamps getWritetimes(ProtocolVersion protocolVersion)
      {
          return getOutput(protocolVersion) == null
                 ? ColumnTimestamps.NO_TIMESTAMP
                 : selected.getWritetimes(protocolVersion).get(field);
      }
  
      @Override
      protected ColumnTimestamps getTTLs(ProtocolVersion protocolVersion)
      {
          return getOutput(protocolVersion) == null
                 ? ColumnTimestamps.NO_TIMESTAMP
                 : selected.getTTLs(protocolVersion).get(field);
      }
  
      public AbstractType<?> getType()
      {
          return type.fieldType(field);
      }
  
      public void reset()
      {
          selected.reset();
      }
  
      @Override
      public boolean isTerminal()
      {
          return selected.isTerminal();
      }
  
      @Override
      public String toString()
      {
          return String.format("%s.%s", selected, type.fieldName(field));
      }
  
      private FieldSelector(UserType type, int field, Selector selected)
      {
          super(Kind.FIELD_SELECTOR);
          this.type = type;
          this.field = field;
          this.selected = selected;
      }
  
      @Override
      public boolean equals(Object o)
      {
          if (this == o)
              return true;
  
          if (!(o instanceof FieldSelector))
              return false;
  
          FieldSelector s = (FieldSelector) o;
  
          return Objects.equal(type, s.type)
              && Objects.equal(field, s.field)
              && Objects.equal(selected, s.selected);
      }
  
      @Override
      public int hashCode()
      {
          return Objects.hashCode(type, field, selected);
      }
  
      @Override
      protected int serializedSize(int version)
      {
          return sizeOf(type) + TypeSizes.sizeofUnsignedVInt(field) + serializer.serializedSize(selected, version);
      }
  
      @Override
      protected void serialize(DataOutputPlus out, int version) throws IOException
      {
          writeType(out, type);
          out.writeUnsignedVInt32(field);
          serializer.serialize(selected, out, version);
      }
  }
  