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Object mapper for the Java Driver for YugaByte DB.
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/*
 * Copyright DataStax, Inc.
 *
 * 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.datastax.driver.mapping;

import java.util.List;

/**
 * A naming strategy that builds upon two naming conventions for the Java and Cassandra side.
 *
 * To infer a Cassandra name, the strategy will {@link NamingConvention#split(String) split} the
 * Java name according to the Java convention, and then {@link NamingConvention#join(List) join} the
 * resulting tokens according to the Cassandra convention. For example, a possible implementation
 * might:
 *
 * 

 *   trim a prefix and tokenize on camel case: split("mUserName") = "user, name"
 *   
join with a separator: join("user", "name") => "user_name"
 * 
 */
public class DefaultNamingStrategy implements NamingStrategy {

  private NamingConvention javaConvention;

  private NamingConvention cassandraConvention;

  /**
   * Builds a new instance with the default conventions, namely {@link
   * NamingConventions#LOWER_CAMEL_CASE lower camel case} for the Java convention, and {@link
   * NamingConventions#LOWER_CASE lower case} for the Cassandra convention.
   *
   * For example, a "userName" Java property will be mapped to a "username" column.
   */
  public DefaultNamingStrategy() {
    this(NamingConventions.LOWER_CAMEL_CASE, NamingConventions.LOWER_CASE);
  }

  /**
   * Builds a new instance.
   *
   * @param javaConvention the naming convention that will be used to tokenize the Java property
   *     names.
   * @param cassandraConvention the naming convention that will be used to build the Cassandra names
   *     from the Java tokens.
   */
  public DefaultNamingStrategy(
      NamingConvention javaConvention, NamingConvention cassandraConvention) {
    if (javaConvention == null || cassandraConvention == null) {
      throw new IllegalArgumentException("input/output NamingConvention cannot be null");
    }
    this.javaConvention = javaConvention;
    this.cassandraConvention = cassandraConvention;
  }

  @Override
  public String toCassandraName(String javaPropertyName) {
    return cassandraConvention.join(javaConvention.split(javaPropertyName));
  }
}