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.functions;
  
  import java.nio.ByteBuffer;
  import java.util.Arrays;
  import java.util.List;
  
  import org.apache.cassandra.db.marshal.AbstractType;
  import org.apache.cassandra.transport.ProtocolVersion;
  
  /**
   * Default {@link Arguments} implementation.
   */
  public final class FunctionArguments implements Arguments
  {
      /**
       * An empty {@link FunctionArguments} for the current protocol.
       */
      private static final FunctionArguments EMPTY = new FunctionArguments(ProtocolVersion.CURRENT);
  
      /**
       * The deserializer used to deserialize the columns.
       */
      private final ArgumentDeserializer[] deserializers;
  
      /**
       * The protocol version.
       */
      private final ProtocolVersion version;
  
      /**
       * The deserialized arguments.
       */
      private final Object[] arguments;
  
      /**
       * Creates a new {@link FunctionArguments} for the specified types.
       *
       * @param version the protocol version
       * @param argTypes the argument types
       * @return a new {@link FunctionArguments} for the specified types.
       */
      public static FunctionArguments newInstanceForUdf(ProtocolVersion version, List<UDFDataType> argTypes)
      {
          int size = argTypes.size();
  
          if (size == 0)
              return emptyInstance(version);
  
          ArgumentDeserializer[] deserializers = new ArgumentDeserializer[size];
  
          for (int i = 0; i < size; i++)
              deserializers[i] = argTypes.get(i).getArgumentDeserializer();
  
          return new FunctionArguments(version, deserializers);
      }
  
      @Override
      public ProtocolVersion getProtocolVersion()
      {
          return version;
      }
  
      /**
       * Creates a new {@link FunctionArguments} that does not deserialize the arguments.
       *
       * @param version the protocol version
       * @param numberOfArguments the number of argument
       * @return a new {@link FunctionArguments} for the specified types.
       */
      public static FunctionArguments newNoopInstance(ProtocolVersion version, int numberOfArguments)
      {
          ArgumentDeserializer[] deserializers = new ArgumentDeserializer[numberOfArguments];
          Arrays.fill(deserializers, ArgumentDeserializer.NOOP_DESERIALIZER);
  
          return new FunctionArguments(version, deserializers);
      }
  
      /**
       * Creates an empty {@link FunctionArguments}.
       *
       * @param version the protocol version
       * @return an empty {@link FunctionArguments}
       */
      public static FunctionArguments emptyInstance(ProtocolVersion version)
      {
          if (version == ProtocolVersion.CURRENT)
              return EMPTY;
  
          return new FunctionArguments(version);
      }
  
      /**
       * Creates a new {@link FunctionArguments} for a native function.
       * <p>Native functions can use different {@link ArgumentDeserializer} to avoid instanciating primitive wrappers.</p>
       *
       * @param version the protocol version
       * @param argTypes the argument types
       * @return a new {@link FunctionArguments} for the specified types.
       */
      public static FunctionArguments newInstanceForNativeFunction(ProtocolVersion version, List<AbstractType<?>> argTypes)
      {
          int size = argTypes.size();
  
          if (size == 0)
              return emptyInstance(version);
  
          ArgumentDeserializer[] deserializers = new ArgumentDeserializer[size];
  
          for (int i = 0; i < size; i++)
              deserializers[i] = argTypes.get(i).getArgumentDeserializer();
  
          return new FunctionArguments(version, deserializers);
      }
  
      public FunctionArguments(ProtocolVersion version, ArgumentDeserializer... deserializers)
      {
          this.version = version;
          this.deserializers = deserializers;
          this.arguments = new Object[deserializers.length];
      }
  
      public void set(int i, ByteBuffer buffer)
      {
          arguments[i] = deserializers[i].deserialize(version, buffer);
      }
  
      @Override
      public boolean containsNulls()
      {
          for (int i = 0; i < arguments.length; i++)
          {
              if (arguments[i] == null)
                  return true;
          }
          return false;
      }
  
      @SuppressWarnings("unchecked")
      @Override
      public <T> T get(int i)
      {
          return (T) arguments[i];
      }
  
      @Override
      public int size()
      {
          return arguments.length;
      }
  }
  