Examples with ShardingPlaceholder io.shardingjdbc.core.rewrite.placeholder.ShardingPlaceholder used on opensource projects

Example 1 with ShardingPlaceholder

use of io.shardingjdbc.core.rewrite.placeholder.ShardingPlaceholder in project sharding-jdbc by shardingjdbc.

the class SQLBuilder method toSQL.

/**
 * Convert to SQL string.
 *
 * @param logicAndActualTableMap logic and actual map
 * @param shardingRule sharding rule
 * @return SQL string
 */
public String toSQL(final Map<String, String> logicAndActualTableMap, final ShardingRule shardingRule) {
    StringBuilder result = new StringBuilder();
    for (Object each : segments) {
        if (!(each instanceof ShardingPlaceholder)) {
            result.append(each);
            continue;
        }
        String logicTableName = ((ShardingPlaceholder) each).getLogicTableName();
        String actualTableName = logicAndActualTableMap.get(logicTableName);
        if (each instanceof TablePlaceholder) {
            result.append(null == actualTableName ? logicTableName : actualTableName);
        } else if (each instanceof SchemaPlaceholder) {
            SchemaPlaceholder schemaPlaceholder = (SchemaPlaceholder) each;
            Optional<TableRule> tableRule = shardingRule.tryFindTableRuleByActualTable(actualTableName);
            if (!tableRule.isPresent() && Strings.isNullOrEmpty(shardingRule.getDefaultDataSourceName())) {
                throw new ShardingJdbcException("Cannot found schema name '%s' in sharding rule.", schemaPlaceholder.getLogicSchemaName());
            }
            // TODO 目前只能找到真实数据源名称. 未来需要在初始化sharding rule时创建connection,并验证连接是否正确,并获取出真实的schema的名字, 然后在这里替换actualDataSourceName为actualSchemaName
            // TODO 目前actualDataSourceName必须actualSchemaName一样,才能保证替换schema的场景不出错, 如: show columns xxx
            result.append(tableRule.get().getActualDatasourceNames().iterator().next());
        } else if (each instanceof IndexPlaceholder) {
            IndexPlaceholder indexPlaceholder = (IndexPlaceholder) each;
            result.append(indexPlaceholder.getLogicIndexName());
            if (!Strings.isNullOrEmpty(actualTableName)) {
                result.append("_");
                result.append(actualTableName);
            }
        } else {
            result.append(each);
        }
    }
    return result.toString();
}