code: public int[] batch(String sql, Object[][] params, int[] paramTypes) throws SQLException {
          Connection conn = this.prepareConnection();
  
          try {
              return this.batch(conn, sql, params, paramTypes);
          } finally {
              close(conn);
          }
      }
docs: Execute a batch of SQL INSERT, UPDATE, or DELETE queries.  The
  <code>Connection</code> is retrieved from the <code>DataSource</code>
  set in the constructor.  This <code>Connection</code> must be in
  auto-commit mode or the update will not be saved.
  
  @param sql The SQL to execute.
  @param params An array of query replacement parameters.  Each row in
  this array is one set of batch replacement values.
  @param paramTypes Query replacement parameters types; <code>null</code> is a valid
  value to pass in.
  @return The number of rows updated per statement.
  @throws java.sql.SQLException if a database access error occurs