com.scalar.db.storage.jdbc.JdbcUtils Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of scalardb Show documentation
A universal transaction manager that achieves database-agnostic transactions and distributed transactions that span multiple databases
There is a newer version: 3.14.0
Show newest version
package com.scalar.db.storage.jdbc;

import java.sql.Connection;
import java.sql.JDBCType;
import org.apache.commons.dbcp2.BasicDataSource;

public final class JdbcUtils {
  private JdbcUtils() {}

  public static BasicDataSource initDataSource(JdbcConfig config, RdbEngineStrategy rdbEngine) {
    return initDataSource(config, rdbEngine, false);
  }

  public static BasicDataSource initDataSource(
      JdbcConfig config, RdbEngineStrategy rdbEngine, boolean transactional) {
    BasicDataSource dataSource = new BasicDataSource();

    /*
     * We need to set the driver class of an underlying database to the dataSource in order
     * to avoid the "No suitable driver" error in case when ServiceLoader in java.sql.DriverManager
     * doesn't work (e.g., when we dynamically load a driver class from a fatJar).
     */
    dataSource.setDriver(rdbEngine.getDriver());

    dataSource.setUrl(config.getJdbcUrl());
    config.getUsername().ifPresent(dataSource::setUsername);
    config.getPassword().ifPresent(dataSource::setPassword);

    if (transactional) {
      dataSource.setDefaultAutoCommit(false);
      dataSource.setAutoCommitOnReturn(false);
      // if transactional, the default isolation level is SERIALIZABLE
      dataSource.setDefaultTransactionIsolation(Connection.TRANSACTION_SERIALIZABLE);
    }

    config
        .getIsolation()
        .ifPresent(
            isolation -> {
              switch (isolation) {
                case READ_UNCOMMITTED:
                  dataSource.setDefaultTransactionIsolation(
                      Connection.TRANSACTION_READ_UNCOMMITTED);
                  break;
                case READ_COMMITTED:
                  dataSource.setDefaultTransactionIsolation(Connection.TRANSACTION_READ_COMMITTED);
                  break;
                case REPEATABLE_READ:
                  dataSource.setDefaultTransactionIsolation(Connection.TRANSACTION_REPEATABLE_READ);
                  break;
                case SERIALIZABLE:
                  dataSource.setDefaultTransactionIsolation(Connection.TRANSACTION_SERIALIZABLE);
                  break;
                default:
                  throw new AssertionError();
              }
            });

    dataSource.setMinIdle(config.getConnectionPoolMinIdle());
    dataSource.setMaxIdle(config.getConnectionPoolMaxIdle());
    dataSource.setMaxTotal(config.getConnectionPoolMaxTotal());
    dataSource.setPoolPreparedStatements(config.isPreparedStatementsPoolEnabled());
    dataSource.setMaxOpenPreparedStatements(config.getPreparedStatementsPoolMaxOpen());
    return dataSource;
  }

  public static BasicDataSource initDataSourceForTableMetadata(
      JdbcConfig config, RdbEngineStrategy rdbEngine) {
    BasicDataSource dataSource = new BasicDataSource();

    /*
     * We need to set the driver class of an underlying database to the dataSource in order
     * to avoid the "No suitable driver" error when ServiceLoader in java.sql.DriverManager doesn't
     * work (e.g., when we dynamically load a driver class from a fatJar).
     */
    dataSource.setDriver(rdbEngine.getDriver());

    dataSource.setUrl(config.getJdbcUrl());
    config.getUsername().ifPresent(dataSource::setUsername);
    config.getPassword().ifPresent(dataSource::setPassword);
    dataSource.setMinIdle(config.getTableMetadataConnectionPoolMinIdle());
    dataSource.setMaxIdle(config.getTableMetadataConnectionPoolMaxIdle());
    dataSource.setMaxTotal(config.getTableMetadataConnectionPoolMaxTotal());
    return dataSource;
  }

  public static BasicDataSource initDataSourceForAdmin(
      JdbcConfig config, RdbEngineStrategy rdbEngine) {
    BasicDataSource dataSource = new BasicDataSource();

    /*
     * We need to set the driver class of an underlying database to the dataSource in order
     * to avoid the "No suitable driver" error when ServiceLoader in java.sql.DriverManager doesn't
     * work (e.g., when we dynamically load a driver class from a fatJar).
     */
    dataSource.setDriver(rdbEngine.getDriver());

    dataSource.setUrl(config.getJdbcUrl());
    config.getUsername().ifPresent(dataSource::setUsername);
    config.getPassword().ifPresent(dataSource::setPassword);
    dataSource.setMinIdle(config.getAdminConnectionPoolMinIdle());
    dataSource.setMaxIdle(config.getAdminConnectionPoolMaxIdle());
    dataSource.setMaxTotal(config.getAdminConnectionPoolMaxTotal());
    return dataSource;
  }

  public static boolean isSqlite(JdbcConfig config) {
    return config.getJdbcUrl().startsWith("jdbc:sqlite:");
  }

  /**
   * Get {@code JDBCType} of the specified {@code sqlType}.
   *
   * @param sqlType a type defined in {@code java.sql.Types}
   * @return a JDBCType
   */
  public static JDBCType getJdbcType(int sqlType) {
    JDBCType type;
    switch (sqlType) {
      case 100: // for Oracle BINARY_FLOAT
        type = JDBCType.REAL;
        break;
      case 101: // for Oracle BINARY_DOUBLE
        type = JDBCType.DOUBLE;
        break;
      default:
        try {
          type = JDBCType.valueOf(sqlType);
        } catch (IllegalArgumentException e) {
          type = JDBCType.OTHER;
        }
    }
    return type;
  }
}