Kotlin + Exposed でSQLiteを使用しているときでもBatchInsertを使えるようにする拡張関数

KotlinExposedSQliteBatchInsert.kt

fun <T : Table, E : Any> T.batchInsert(
                data: Iterable<E>,
                ignore: Boolean = false,
                body: BatchInsertStatement.(E) -> Unit
            ): List<ResultRow> {
                if (data.count() == 0) return emptyList()

                val statement = object : SQLServerBatchInsertStatement(this, ignore) {
                    override fun prepareSQL(transaction: Transaction): String {
                        val values = arguments!!
                        val sql = if (values.isEmpty()) ""
                        else {
                            val output = table.autoIncColumn?.let { " RETURNING ${transaction.identity(it)} AS GENERATED_KEYS" }.orEmpty()
                            val toString = QueryBuilder(true).apply {
                                values.appendTo(prefix = "VALUES ") {
                                    it.appendTo(prefix = "(", postfix = ")") { (col, value) ->
                                        registerArgument(col, value)
                                    }
                                }
                                values.appendTo(prefix = output) {}
                            }.toString()
                            toString.substring(0,toString.lastIndex-1)
                        }
                        return transaction.db.dialect.functionProvider.insert(isIgnore, table, values.firstOrNull()?.map { it.first }.orEmpty(), sql, transaction)
                    }
                }
                val result = java.util.ArrayList<ResultRow>()
                fun BatchInsertStatement.handleBatchException(body: BatchInsertStatement.() -> Unit) {
                    try {
                        body()
                    } catch (e: Exception) {
                        execute(TransactionManager.current())
                        result += resultedValues.orEmpty()
                        e.printStackTrace()
                    }
                }

                for (element in data) {
                    statement.handleBatchException { addBatch() }
                    statement.handleBatchException {
                    body(element)
                    }
                }
                if (statement.arguments().isNotEmpty()) {
                    statement.execute(TransactionManager.current())
                    result += statement.resultedValues.orEmpty()
                }
                return result
            }