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 com.datastax.oss.driver.api.core;
  
  import com.datastax.oss.driver.api.core.metadata.Node;
  import edu.umd.cs.findbugs.annotations.NonNull;
  import java.util.Objects;
  
  /**
   * Indicates that a {@link Node} was selected in a query plan, but it had no connection available.
   *
   * <p>A common reason to encounter this error is when the configured number of connections per node
   * and requests per connection is not high enough to absorb the overall request rate. This can be
   * mitigated by tuning the following options:
   *
   * <ul>
   *   <li>{@code advanced.connection.pool.local.size};
   *   <li>{@code advanced.connection.pool.remote.size};
   *   <li>{@code advanced.connection.max-requests-per-connection}.
   * </ul>
   *
   * See {@code reference.conf} for more details.
   *
   * <p>Another possibility is when you are trying to direct a request {@linkplain
   * com.datastax.oss.driver.api.core.cql.Statement#setNode(Node) to a particular node}, but that node
   * has no connections available.
   */
  public class NodeUnavailableException extends DriverException {
  
    private final Node node;
  
    public NodeUnavailableException(Node node) {
      super("No connection was available to " + node, null, null, true);
      this.node = Objects.requireNonNull(node);
    }
  
    @NonNull
    public Node getNode() {
      return node;
    }
  
    @Override
    @NonNull
    public DriverException copy() {
      return new NodeUnavailableException(node);
    }
  }
  