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A Shaded CQL ActivityType driver for http://nosqlbench.io/
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/*
 * Copyright DataStax, Inc.
 *
 * This software can be used solely with DataStax Enterprise. Please consult the license at
 * http://www.datastax.com/terms/datastax-dse-driver-license-terms
 */
package com.datastax.driver.core.schemabuilder;

import com.datastax.driver.core.CodecRegistry;
import com.datastax.driver.core.Metadata;
import com.datastax.driver.core.ProtocolVersion;
import com.datastax.driver.core.RegularStatement;
import com.datastax.driver.core.Statement;
import com.google.common.base.Strings;
import java.nio.ByteBuffer;
import java.util.Map;

/** A DDL statement generated by {@link SchemaBuilder}. */
public abstract class SchemaStatement extends RegularStatement {

  static final String STATEMENT_START = "\n\t";
  static final String COLUMN_FORMATTING = "\n\t\t";

  private volatile String cache;

  private String keyspace;

  abstract String buildInternal();

  @Override
  public String getQueryString(CodecRegistry codecRegistry) {
    if (cache == null) {
      cache = buildInternal();
    }
    return cache;
  }

  @Override
  public ByteBuffer[] getValues(ProtocolVersion protocolVersion, CodecRegistry codecRegistry) {
    // DDL statements never have values
    return new ByteBuffer[0];
  }

  @Override
  public boolean hasValues(CodecRegistry codecRegistry) {
    return false;
  }

  @Override
  public Map getNamedValues(
      ProtocolVersion protocolVersion, CodecRegistry codecRegistry) {
    // DDL statements never have values
    return null;
  }

  @Override
  public boolean usesNamedValues() {
    return false;
  }

  @Override
  public String getKeyspace() {
    return keyspace;
  }

  /**
   * Sets the keyspace this query operates on.
   *
   * This method allows you to manually provide a keyspace for this query. It is used for the
   * following:
   *
   * 

   *   To indicate to cassandra what keyspace the statement is applicable to (protocol V5+
   *       only). This is useful when the query does not provide an explicit keyspace and you want
   *       to override the session's keyspace.
   *   
By {@link com.datastax.driver.core.policies.TokenAwarePolicy} to help identify which
   *       replicas are applicable to send this statement to.
   * 
   *
   * Do note that if the query does not use a fully qualified keyspace, then you do not need to set
   * the keyspace through this method as the currently logged in keyspace will be used if it is set.
   *
   * Note: This expects the internal representation of the keyspace. In the typical case,
   * the internal representation is equivalent to the CQL representation. However, if you are using
   * a keyspace that requires the use of quotes in CQL (a quoted identifier), i.e.: "MyKS", this
   * method will return the unquoted representation instead, i.e. MyKS.
   *
   * @param keyspace the name of the keyspace this query operates on.
   * @return this {@code SchemaStatement} object.
   * @see Statement#getKeyspace
   */
  public SchemaStatement setKeyspace(String keyspace) {
    this.keyspace = keyspace;
    return this;
  }

  /**
   * {@inheritDoc}
   *
   * @param protocolVersion unused by this implementation (the key is always null for schema
   *     statements).
   * @param codecRegistry unused by this implementation (the key is always null for schema
   *     statements).
   */
  @Override
  public ByteBuffer getRoutingKey(ProtocolVersion protocolVersion, CodecRegistry codecRegistry) {
    return null; // there is no token awareness for DDL statements
  }

  static void validateNotEmpty(String columnName, String label) {
    if (Strings.isNullOrEmpty(columnName)) {
      throw new IllegalArgumentException(label + " should not be null or blank");
    }
  }

  static void validateNotNull(Object value, String label) {
    if (value == null) {
      throw new IllegalArgumentException(label + " should not be null");
    }
  }

  static void validateNotKeyWord(String label, String message) {
    if (Metadata.isReservedCqlKeyword(label)) {
      throw new IllegalArgumentException(message);
    }
  }

  static SchemaStatement fromQueryString(final String queryString) {
    return new SchemaStatement() {
      @Override
      public String buildInternal() {
        return queryString;
      }
    };
  }

  StatementStart asStatementStart() {
    return new StatementStart() {
      @Override
      public String buildInternal() {
        return SchemaStatement.this.buildInternal();
      }
    };
  }
}