Examples with TimeLimiter com.google.common.util.concurrent.TimeLimiter used on opensource projects

Example 6 with TimeLimiter

use of com.google.common.util.concurrent.TimeLimiter in project presto by prestodb.

the class QueryRewriter method getColumns.

private List<Column> getColumns(Connection connection, CreateTableAsSelect createTableAsSelect) throws SQLException {
    com.facebook.presto.sql.tree.Query createSelectClause = createTableAsSelect.getQuery();
    // Rewrite the query to select zero rows, so that we can get the column names and types
    QueryBody innerQuery = createSelectClause.getQueryBody();
    com.facebook.presto.sql.tree.Query zeroRowsQuery;
    if (innerQuery instanceof QuerySpecification) {
        QuerySpecification querySpecification = (QuerySpecification) innerQuery;
        innerQuery = new QuerySpecification(querySpecification.getSelect(), querySpecification.getFrom(), querySpecification.getWhere(), querySpecification.getGroupBy(), querySpecification.getHaving(), querySpecification.getOrderBy(), Optional.of("0"));
        zeroRowsQuery = new com.facebook.presto.sql.tree.Query(createSelectClause.getWith(), innerQuery, Optional.empty(), Optional.empty());
    } else {
        zeroRowsQuery = new com.facebook.presto.sql.tree.Query(createSelectClause.getWith(), innerQuery, Optional.empty(), Optional.of("0"));
    }
    ImmutableList.Builder<Column> columns = ImmutableList.builder();
    try (java.sql.Statement jdbcStatement = connection.createStatement()) {
        TimeLimiter limiter = new SimpleTimeLimiter();
        java.sql.Statement limitedStatement = limiter.newProxy(jdbcStatement, java.sql.Statement.class, timeout.toMillis(), TimeUnit.MILLISECONDS);
        try (ResultSet resultSet = limitedStatement.executeQuery(formatSql(zeroRowsQuery, Optional.empty()))) {
            ResultSetMetaData metaData = resultSet.getMetaData();
            for (int i = 1; i <= metaData.getColumnCount(); i++) {
                String name = metaData.getColumnName(i);
                int type = metaData.getColumnType(i);
                columns.add(new Column(name, APPROXIMATE_TYPES.contains(type)));
            }
        }
    }
    return columns.build();
}