Updated package versions, updated web server tests. (#207)

* Updated all package versions including kotlin. Updated all web-server tests to run.

* Changed the java version of the tests. OpenDC now only supports java 19.

* small update

* test update

* new update

* updated docker version to 19

* updated docker version to 19

7 files changed, 258 insertions, 220 deletions

diff --git a/opendc-trace/opendc-trace-wtf/build.gradle.kts b/opendc-trace/opendc-trace-wtf/build.gradle.kts
index 599087e1..a3119e5e 100644
--- a/opendc-trace/opendc-trace-wtf/build.gradle.kts
+++ b/opendc-trace/opendc-trace-wtf/build.gradle.kts
@@ -22,7 +22,7 @@
 
 description = "Support for Workflow Trace Format (WTF) traces in OpenDC"
 
-/* Build configuration */
+// Build configuration
 plugins {
     `kotlin-library-conventions`
 }
diff --git a/opendc-trace/opendc-trace-wtf/src/main/kotlin/org/opendc/trace/wtf/WtfTaskTableReader.kt b/opendc-trace/opendc-trace-wtf/src/main/kotlin/org/opendc/trace/wtf/WtfTaskTableReader.kt
index 73c1b8a9..95582388 100644
--- a/opendc-trace/opendc-trace-wtf/src/main/kotlin/org/opendc/trace/wtf/WtfTaskTableReader.kt
+++ b/opendc-trace/opendc-trace-wtf/src/main/kotlin/org/opendc/trace/wtf/WtfTaskTableReader.kt
@@ -62,38 +62,38 @@ internal class WtfTaskTableReader(private val reader: LocalParquetReader<Task>)
         }
     }
 
-    private val COL_ID = 0
-    private val COL_WORKFLOW_ID = 1
-    private val COL_SUBMIT_TIME = 2
-    private val COL_WAIT_TIME = 3
-    private val COL_RUNTIME = 4
-    private val COL_REQ_NCPUS = 5
-    private val COL_PARENTS = 6
-    private val COL_CHILDREN = 7
-    private val COL_GROUP_ID = 8
-    private val COL_USER_ID = 9
-
-    private val TYPE_PARENTS = TableColumnType.Set(TableColumnType.String)
-    private val TYPE_CHILDREN = TableColumnType.Set(TableColumnType.String)
+    private val colID = 0
+    private val colWorkflowID = 1
+    private val colSubmitTime = 2
+    private val colWaitTime = 3
+    private val colRuntime = 4
+    private val colReqNcpus = 5
+    private val colParents = 6
+    private val colChildren = 7
+    private val colGroupID = 8
+    private val colUserID = 9
+
+    private val typeParents = TableColumnType.Set(TableColumnType.String)
+    private val typeChildren = TableColumnType.Set(TableColumnType.String)
 
     override fun resolve(name: String): Int {
         return when (name) {
-            TASK_ID -> COL_ID
-            TASK_WORKFLOW_ID -> COL_WORKFLOW_ID
-            TASK_SUBMIT_TIME -> COL_SUBMIT_TIME
-            TASK_WAIT_TIME -> COL_WAIT_TIME
-            TASK_RUNTIME -> COL_RUNTIME
-            TASK_REQ_NCPUS -> COL_REQ_NCPUS
-            TASK_PARENTS -> COL_PARENTS
-            TASK_CHILDREN -> COL_CHILDREN
-            TASK_GROUP_ID -> COL_GROUP_ID
-            TASK_USER_ID -> COL_USER_ID
+            TASK_ID -> colID
+            TASK_WORKFLOW_ID -> colWorkflowID
+            TASK_SUBMIT_TIME -> colSubmitTime
+            TASK_WAIT_TIME -> colWaitTime
+            TASK_RUNTIME -> colRuntime
+            TASK_REQ_NCPUS -> colReqNcpus
+            TASK_PARENTS -> colParents
+            TASK_CHILDREN -> colChildren
+            TASK_GROUP_ID -> colGroupID
+            TASK_USER_ID -> colUserID
             else -> -1
         }
     }
 
     override fun isNull(index: Int): Boolean {
-        require(index in COL_ID..COL_USER_ID) { "Invalid column index" }
+        require(index in colID..colUserID) { "Invalid column index" }
         return false
     }
 
@@ -105,9 +105,9 @@ internal class WtfTaskTableReader(private val reader: LocalParquetReader<Task>)
         val record = checkNotNull(record) { "Reader in invalid state" }
 
         return when (index) {
-            COL_REQ_NCPUS -> record.requestedCpus
-            COL_GROUP_ID -> record.groupId
-            COL_USER_ID -> record.userId
+            colReqNcpus -> record.requestedCpus
+            colGroupID -> record.groupId
+            colUserID -> record.userId
             else -> throw IllegalArgumentException("Invalid column")
         }
     }
@@ -127,8 +127,8 @@ internal class WtfTaskTableReader(private val reader: LocalParquetReader<Task>)
     override fun getString(index: Int): String {
         val record = checkNotNull(record) { "Reader in invalid state" }
         return when (index) {
-            COL_ID -> record.id
-            COL_WORKFLOW_ID -> record.workflowId
+            colID -> record.id
+            colWorkflowID -> record.workflowId
             else -> throw IllegalArgumentException("Invalid column")
         }
     }
@@ -140,7 +140,7 @@ internal class WtfTaskTableReader(private val reader: LocalParquetReader<Task>)
     override fun getInstant(index: Int): Instant {
         val record = checkNotNull(record) { "Reader in invalid state" }
         return when (index) {
-            COL_SUBMIT_TIME -> record.submitTime
+            colSubmitTime -> record.submitTime
             else -> throw IllegalArgumentException("Invalid column")
         }
     }
@@ -148,26 +148,36 @@ internal class WtfTaskTableReader(private val reader: LocalParquetReader<Task>)
     override fun getDuration(index: Int): Duration {
         val record = checkNotNull(record) { "Reader in invalid state" }
         return when (index) {
-            COL_WAIT_TIME -> record.waitTime
-            COL_RUNTIME -> record.runtime
+            colWaitTime -> record.waitTime
+            colRuntime -> record.runtime
             else -> throw IllegalArgumentException("Invalid column")
         }
     }
 
-    override fun <T> getList(index: Int, elementType: Class<T>): List<T>? {
+    override fun <T> getList(
+        index: Int,
+        elementType: Class<T>,
+    ): List<T>? {
         throw IllegalArgumentException("Invalid column")
     }
 
-    override fun <T> getSet(index: Int, elementType: Class<T>): Set<T>? {
+    override fun <T> getSet(
+        index: Int,
+        elementType: Class<T>,
+    ): Set<T>? {
         val record = checkNotNull(record) { "Reader in invalid state" }
         return when (index) {
-            COL_PARENTS -> TYPE_PARENTS.convertTo(record.parents, elementType)
-            COL_CHILDREN -> TYPE_CHILDREN.convertTo(record.children, elementType)
+            colParents -> typeParents.convertTo(record.parents, elementType)
+            colChildren -> typeChildren.convertTo(record.children, elementType)
             else -> throw IllegalArgumentException("Invalid column")
         }
     }
 
-    override fun <K, V> getMap(index: Int, keyType: Class<K>, valueType: Class<V>): Map<K, V>? {
+    override fun <K, V> getMap(
+        index: Int,
+        keyType: Class<K>,
+        valueType: Class<V>,
+    ): Map<K, V>? {
         throw IllegalArgumentException("Invalid column")
     }
 
diff --git a/opendc-trace/opendc-trace-wtf/src/main/kotlin/org/opendc/trace/wtf/WtfTraceFormat.kt b/opendc-trace/opendc-trace-wtf/src/main/kotlin/org/opendc/trace/wtf/WtfTraceFormat.kt
index c25b512c..1386d2ef 100644
--- a/opendc-trace/opendc-trace-wtf/src/main/kotlin/org/opendc/trace/wtf/WtfTraceFormat.kt
+++ b/opendc-trace/opendc-trace-wtf/src/main/kotlin/org/opendc/trace/wtf/WtfTraceFormat.kt
@@ -55,27 +55,35 @@ public class WtfTraceFormat : TraceFormat {
 
     override fun getTables(path: Path): List<String> = listOf(TABLE_TASKS)
 
-    override fun getDetails(path: Path, table: String): TableDetails {
+    override fun getDetails(
+        path: Path,
+        table: String,
+    ): TableDetails {
         return when (table) {
-            TABLE_TASKS -> TableDetails(
-                listOf(
-                    TableColumn(TASK_ID, TableColumnType.String),
-                    TableColumn(TASK_WORKFLOW_ID, TableColumnType.String),
-                    TableColumn(TASK_SUBMIT_TIME, TableColumnType.Instant),
-                    TableColumn(TASK_WAIT_TIME, TableColumnType.Duration),
-                    TableColumn(TASK_RUNTIME, TableColumnType.Duration),
-                    TableColumn(TASK_REQ_NCPUS, TableColumnType.Int),
-                    TableColumn(TASK_PARENTS, TableColumnType.Set(TableColumnType.String)),
-                    TableColumn(TASK_CHILDREN, TableColumnType.Set(TableColumnType.String)),
-                    TableColumn(TASK_GROUP_ID, TableColumnType.Int),
-                    TableColumn(TASK_USER_ID, TableColumnType.Int)
+            TABLE_TASKS ->
+                TableDetails(
+                    listOf(
+                        TableColumn(TASK_ID, TableColumnType.String),
+                        TableColumn(TASK_WORKFLOW_ID, TableColumnType.String),
+                        TableColumn(TASK_SUBMIT_TIME, TableColumnType.Instant),
+                        TableColumn(TASK_WAIT_TIME, TableColumnType.Duration),
+                        TableColumn(TASK_RUNTIME, TableColumnType.Duration),
+                        TableColumn(TASK_REQ_NCPUS, TableColumnType.Int),
+                        TableColumn(TASK_PARENTS, TableColumnType.Set(TableColumnType.String)),
+                        TableColumn(TASK_CHILDREN, TableColumnType.Set(TableColumnType.String)),
+                        TableColumn(TASK_GROUP_ID, TableColumnType.Int),
+                        TableColumn(TASK_USER_ID, TableColumnType.Int),
+                    ),
                 )
-            )
             else -> throw IllegalArgumentException("Table $table not supported")
         }
     }
 
-    override fun newReader(path: Path, table: String, projection: List<String>?): TableReader {
+    override fun newReader(
+        path: Path,
+        table: String,
+        projection: List<String>?,
+    ): TableReader {
         return when (table) {
             TABLE_TASKS -> {
                 val reader = LocalParquetReader(path.resolve("tasks/schema-1.0"), TaskReadSupport(projection), strictTyping = false)
@@ -85,7 +93,10 @@ public class WtfTraceFormat : TraceFormat {
         }
     }
 
-    override fun newWriter(path: Path, table: String): TableWriter {
+    override fun newWriter(
+        path: Path,
+        table: String,
+    ): TableWriter {
         throw UnsupportedOperationException("Writing not supported for this format")
     }
 }
diff --git a/opendc-trace/opendc-trace-wtf/src/main/kotlin/org/opendc/trace/wtf/parquet/Task.kt b/opendc-trace/opendc-trace-wtf/src/main/kotlin/org/opendc/trace/wtf/parquet/Task.kt
index 71557f96..a1db0cab 100644
--- a/opendc-trace/opendc-trace-wtf/src/main/kotlin/org/opendc/trace/wtf/parquet/Task.kt
+++ b/opendc-trace/opendc-trace-wtf/src/main/kotlin/org/opendc/trace/wtf/parquet/Task.kt
@@ -38,5 +38,5 @@ internal data class Task(
     val groupId: Int,
     val userId: Int,
     val parents: Set<String>,
-    val children: Set<String>
+    val children: Set<String>,
 )
diff --git a/opendc-trace/opendc-trace-wtf/src/main/kotlin/org/opendc/trace/wtf/parquet/TaskReadSupport.kt b/opendc-trace/opendc-trace-wtf/src/main/kotlin/org/opendc/trace/wtf/parquet/TaskReadSupport.kt
index 33be38d4..1f9c506d 100644
--- a/opendc-trace/opendc-trace-wtf/src/main/kotlin/org/opendc/trace/wtf/parquet/TaskReadSupport.kt
+++ b/opendc-trace/opendc-trace-wtf/src/main/kotlin/org/opendc/trace/wtf/parquet/TaskReadSupport.kt
@@ -51,18 +51,19 @@ internal class TaskReadSupport(private val projection: List<String>?) : ReadSupp
     /**
      * Mapping of table columns to their Parquet column names.
      */
-    private val colMap = mapOf(
-        TASK_ID to "id",
-        TASK_WORKFLOW_ID to "workflow_id",
-        TASK_SUBMIT_TIME to "ts_submit",
-        TASK_WAIT_TIME to "wait_time",
-        TASK_RUNTIME to "runtime",
-        TASK_REQ_NCPUS to "resource_amount_requested",
-        TASK_PARENTS to "parents",
-        TASK_CHILDREN to "children",
-        TASK_GROUP_ID to "group_id",
-        TASK_USER_ID to "user_id"
-    )
+    private val colMap =
+        mapOf(
+            TASK_ID to "id",
+            TASK_WORKFLOW_ID to "workflow_id",
+            TASK_SUBMIT_TIME to "ts_submit",
+            TASK_WAIT_TIME to "wait_time",
+            TASK_RUNTIME to "runtime",
+            TASK_REQ_NCPUS to "resource_amount_requested",
+            TASK_PARENTS to "parents",
+            TASK_CHILDREN to "children",
+            TASK_GROUP_ID to "group_id",
+            TASK_USER_ID to "user_id",
+        )
 
     override fun init(context: InitContext): ReadContext {
         val projectedSchema =
@@ -87,7 +88,7 @@ internal class TaskReadSupport(private val projection: List<String>?) : ReadSupp
         configuration: Configuration,
         keyValueMetaData: Map<String, String>,
         fileSchema: MessageType,
-        readContext: ReadContext
+        readContext: ReadContext,
     ): RecordMaterializer<Task> = TaskRecordMaterializer(readContext.requestedSchema)
 
     companion object {
@@ -95,52 +96,53 @@ internal class TaskReadSupport(private val projection: List<String>?) : ReadSupp
          * Parquet read schema for the "tasks" table in the trace.
          */
         @JvmStatic
-        val READ_SCHEMA: MessageType = Types.buildMessage()
-            .addFields(
-                Types
-                    .optional(PrimitiveType.PrimitiveTypeName.INT64)
-                    .named("id"),
-                Types
-                    .optional(PrimitiveType.PrimitiveTypeName.INT64)
-                    .named("workflow_id"),
-                Types
-                    .optional(PrimitiveType.PrimitiveTypeName.INT64)
-                    .`as`(LogicalTypeAnnotation.timestampType(true, LogicalTypeAnnotation.TimeUnit.MILLIS))
-                    .named("ts_submit"),
-                Types
-                    .optional(PrimitiveType.PrimitiveTypeName.INT64)
-                    .named("wait_time"),
-                Types
-                    .optional(PrimitiveType.PrimitiveTypeName.INT64)
-                    .named("runtime"),
-                Types
-                    .optional(PrimitiveType.PrimitiveTypeName.DOUBLE)
-                    .named("resource_amount_requested"),
-                Types
-                    .optional(PrimitiveType.PrimitiveTypeName.INT32)
-                    .named("user_id"),
-                Types
-                    .optional(PrimitiveType.PrimitiveTypeName.INT32)
-                    .named("group_id"),
-                Types
-                    .buildGroup(Type.Repetition.OPTIONAL)
-                    .addField(
-                        Types.repeatedGroup()
-                            .addField(Types.optional(PrimitiveType.PrimitiveTypeName.INT64).named("item"))
-                            .named("list")
-                    )
-                    .`as`(LogicalTypeAnnotation.listType())
-                    .named("children"),
-                Types
-                    .buildGroup(Type.Repetition.OPTIONAL)
-                    .addField(
-                        Types.repeatedGroup()
-                            .addField(Types.optional(PrimitiveType.PrimitiveTypeName.INT64).named("item"))
-                            .named("list")
-                    )
-                    .`as`(LogicalTypeAnnotation.listType())
-                    .named("parents")
-            )
-            .named("task")
+        val READ_SCHEMA: MessageType =
+            Types.buildMessage()
+                .addFields(
+                    Types
+                        .optional(PrimitiveType.PrimitiveTypeName.INT64)
+                        .named("id"),
+                    Types
+                        .optional(PrimitiveType.PrimitiveTypeName.INT64)
+                        .named("workflow_id"),
+                    Types
+                        .optional(PrimitiveType.PrimitiveTypeName.INT64)
+                        .`as`(LogicalTypeAnnotation.timestampType(true, LogicalTypeAnnotation.TimeUnit.MILLIS))
+                        .named("ts_submit"),
+                    Types
+                        .optional(PrimitiveType.PrimitiveTypeName.INT64)
+                        .named("wait_time"),
+                    Types
+                        .optional(PrimitiveType.PrimitiveTypeName.INT64)
+                        .named("runtime"),
+                    Types
+                        .optional(PrimitiveType.PrimitiveTypeName.DOUBLE)
+                        .named("resource_amount_requested"),
+                    Types
+                        .optional(PrimitiveType.PrimitiveTypeName.INT32)
+                        .named("user_id"),
+                    Types
+                        .optional(PrimitiveType.PrimitiveTypeName.INT32)
+                        .named("group_id"),
+                    Types
+                        .buildGroup(Type.Repetition.OPTIONAL)
+                        .addField(
+                            Types.repeatedGroup()
+                                .addField(Types.optional(PrimitiveType.PrimitiveTypeName.INT64).named("item"))
+                                .named("list"),
+                        )
+                        .`as`(LogicalTypeAnnotation.listType())
+                        .named("children"),
+                    Types
+                        .buildGroup(Type.Repetition.OPTIONAL)
+                        .addField(
+                            Types.repeatedGroup()
+                                .addField(Types.optional(PrimitiveType.PrimitiveTypeName.INT64).named("item"))
+                                .named("list"),
+                        )
+                        .`as`(LogicalTypeAnnotation.listType())
+                        .named("parents"),
+                )
+                .named("task")
     }
 }
diff --git a/opendc-trace/opendc-trace-wtf/src/main/kotlin/org/opendc/trace/wtf/parquet/TaskRecordMaterializer.kt b/opendc-trace/opendc-trace-wtf/src/main/kotlin/org/opendc/trace/wtf/parquet/TaskRecordMaterializer.kt
index 055be0c3..412a4f8b 100644
--- a/opendc-trace/opendc-trace-wtf/src/main/kotlin/org/opendc/trace/wtf/parquet/TaskRecordMaterializer.kt
+++ b/opendc-trace/opendc-trace-wtf/src/main/kotlin/org/opendc/trace/wtf/parquet/TaskRecordMaterializer.kt
@@ -39,102 +39,113 @@ internal class TaskRecordMaterializer(schema: MessageType) : RecordMaterializer<
     /**
      * State of current record being read.
      */
-    private var _id = ""
-    private var _workflowId = ""
-    private var _submitTime = Instant.MIN
-    private var _waitTime = Duration.ZERO
-    private var _runtime = Duration.ZERO
-    private var _requestedCpus = 0
-    private var _groupId = 0
-    private var _userId = 0
-    private var _parents = mutableSetOf<String>()
-    private var _children = mutableSetOf<String>()
+    private var localID = ""
+    private var localWorkflowID = ""
+    private var localSubmitTime = Instant.MIN
+    private var localWaitTime = Duration.ZERO
+    private var localRuntime = Duration.ZERO
+    private var localRequestedCpus = 0
+    private var localGroupId = 0
+    private var localUserId = 0
+    private var localParents = mutableSetOf<String>()
+    private var localChildren = mutableSetOf<String>()
 
     /**
      * Root converter for the record.
      */
-    private val root = object : GroupConverter() {
-        /**
-         * The converters for the columns of the schema.
-         */
-        private val converters = schema.fields.map { type ->
-            when (type.name) {
-                "id" -> object : PrimitiveConverter() {
-                    override fun addLong(value: Long) {
-                        _id = value.toString()
+    private val root =
+        object : GroupConverter() {
+            /**
+             * The converters for the columns of the schema.
+             */
+            private val converters =
+                schema.fields.map { type ->
+                    when (type.name) {
+                        "id" ->
+                            object : PrimitiveConverter() {
+                                override fun addLong(value: Long) {
+                                    localID = value.toString()
+                                }
+                            }
+                        "workflow_id" ->
+                            object : PrimitiveConverter() {
+                                override fun addLong(value: Long) {
+                                    localWorkflowID = value.toString()
+                                }
+                            }
+                        "ts_submit" ->
+                            object : PrimitiveConverter() {
+                                override fun addLong(value: Long) {
+                                    localSubmitTime = Instant.ofEpochMilli(value)
+                                }
+                            }
+                        "wait_time" ->
+                            object : PrimitiveConverter() {
+                                override fun addLong(value: Long) {
+                                    localWaitTime = Duration.ofMillis(value)
+                                }
+                            }
+                        "runtime" ->
+                            object : PrimitiveConverter() {
+                                override fun addLong(value: Long) {
+                                    localRuntime = Duration.ofMillis(value)
+                                }
+                            }
+                        "resource_amount_requested" ->
+                            object : PrimitiveConverter() {
+                                override fun addDouble(value: Double) {
+                                    localRequestedCpus = value.roundToInt()
+                                }
+                            }
+                        "group_id" ->
+                            object : PrimitiveConverter() {
+                                override fun addInt(value: Int) {
+                                    localGroupId = value
+                                }
+                            }
+                        "user_id" ->
+                            object : PrimitiveConverter() {
+                                override fun addInt(value: Int) {
+                                    localUserId = value
+                                }
+                            }
+                        "children" -> RelationConverter(localChildren)
+                        "parents" -> RelationConverter(localParents)
+                        else -> error("Unknown column $type")
                     }
                 }
-                "workflow_id" -> object : PrimitiveConverter() {
-                    override fun addLong(value: Long) {
-                        _workflowId = value.toString()
-                    }
-                }
-                "ts_submit" -> object : PrimitiveConverter() {
-                    override fun addLong(value: Long) {
-                        _submitTime = Instant.ofEpochMilli(value)
-                    }
-                }
-                "wait_time" -> object : PrimitiveConverter() {
-                    override fun addLong(value: Long) {
-                        _waitTime = Duration.ofMillis(value)
-                    }
-                }
-                "runtime" -> object : PrimitiveConverter() {
-                    override fun addLong(value: Long) {
-                        _runtime = Duration.ofMillis(value)
-                    }
-                }
-                "resource_amount_requested" -> object : PrimitiveConverter() {
-                    override fun addDouble(value: Double) {
-                        _requestedCpus = value.roundToInt()
-                    }
-                }
-                "group_id" -> object : PrimitiveConverter() {
-                    override fun addInt(value: Int) {
-                        _groupId = value
-                    }
-                }
-                "user_id" -> object : PrimitiveConverter() {
-                    override fun addInt(value: Int) {
-                        _userId = value
-                    }
-                }
-                "children" -> RelationConverter(_children)
-                "parents" -> RelationConverter(_parents)
-                else -> error("Unknown column $type")
-            }
-        }
 
-        override fun start() {
-            _id = ""
-            _workflowId = ""
-            _submitTime = Instant.MIN
-            _waitTime = Duration.ZERO
-            _runtime = Duration.ZERO
-            _requestedCpus = 0
-            _groupId = 0
-            _userId = 0
-            _parents.clear()
-            _children.clear()
-        }
+            override fun start() {
+                localID = ""
+                localWorkflowID = ""
+                localSubmitTime = Instant.MIN
+                localWaitTime = Duration.ZERO
+                localRuntime = Duration.ZERO
+                localRequestedCpus = 0
+                localGroupId = 0
+                localUserId = 0
+                localParents.clear()
+                localChildren.clear()
+            }
 
-        override fun end() {}
+            override fun end() {}
 
-        override fun getConverter(fieldIndex: Int): Converter = converters[fieldIndex]
-    }
+            override fun getConverter(fieldIndex: Int): Converter = converters[fieldIndex]
+        }
 
-    override fun getCurrentRecord(): Task = Task(
-        _id,
-        _workflowId,
-        _submitTime,
-        _waitTime,
-        _runtime,
-        _requestedCpus,
-        _groupId,
-        _userId,
-        _parents.toSet(),
-        _children.toSet()
-    )
+    override fun getCurrentRecord(): Task =
+        Task(
+            localID,
+            localWorkflowID,
+            localSubmitTime,
+            localWaitTime,
+            localRuntime,
+            localRequestedCpus,
+            localGroupId,
+            localUserId,
+            localParents.toSet(),
+            localChildren.toSet(),
+        )
 
     override fun getRootConverter(): GroupConverter = root
 
@@ -142,25 +153,28 @@ internal class TaskRecordMaterializer(schema: MessageType) : RecordMaterializer<
      * Helper class to convert parent and child relations and add them to [relations].
      */
     private class RelationConverter(private val relations: MutableSet<String>) : GroupConverter() {
-        private val entryConverter = object : PrimitiveConverter() {
-            override fun addLong(value: Long) {
-                relations.add(value.toString())
-            }
+        private val entryConverter =
+            object : PrimitiveConverter() {
+                override fun addLong(value: Long) {
+                    relations.add(value.toString())
+                }
 
-            override fun addDouble(value: Double) {
-                relations.add(value.roundToLong().toString())
+                override fun addDouble(value: Double) {
+                    relations.add(value.roundToLong().toString())
+                }
             }
-        }
 
-        private val listConverter = object : GroupConverter() {
-            override fun getConverter(fieldIndex: Int): Converter {
-                require(fieldIndex == 0)
-                return entryConverter
-            }
+        private val listConverter =
+            object : GroupConverter() {
+                override fun getConverter(fieldIndex: Int): Converter {
+                    require(fieldIndex == 0)
+                    return entryConverter
+                }
 
-            override fun start() {}
-            override fun end() {}
-        }
+                override fun start() {}
+
+                override fun end() {}
+            }
 
         override fun getConverter(fieldIndex: Int): Converter {
             require(fieldIndex == 0)
@@ -168,6 +182,7 @@ internal class TaskRecordMaterializer(schema: MessageType) : RecordMaterializer<
         }
 
         override fun start() {}
+
         override fun end() {}
     }
 }
diff --git a/opendc-trace/opendc-trace-wtf/src/test/kotlin/org/opendc/trace/wtf/WtfTraceFormatTest.kt b/opendc-trace/opendc-trace-wtf/src/test/kotlin/org/opendc/trace/wtf/WtfTraceFormatTest.kt
index 0457098c..ad49cce0 100644
--- a/opendc-trace/opendc-trace-wtf/src/test/kotlin/org/opendc/trace/wtf/WtfTraceFormatTest.kt
+++ b/opendc-trace/opendc-trace-wtf/src/test/kotlin/org/opendc/trace/wtf/WtfTraceFormatTest.kt
@@ -87,9 +87,9 @@ class WtfTraceFormatTest {
             {
                 assertEquals(
                     setOf("584055316413447529", "133113685133695608", "1008582348422865408"),
-                    reader.getSet(TASK_PARENTS, String::class.java)
+                    reader.getSet(TASK_PARENTS, String::class.java),
                 )
-            }
+            },
         )
 
         assertAll(
@@ -101,9 +101,9 @@ class WtfTraceFormatTest {
             {
                 assertEquals(
                     setOf("584055316413447529", "133113685133695608", "1008582348422865408"),
-                    reader.getSet(TASK_PARENTS, String::class.java)
+                    reader.getSet(TASK_PARENTS, String::class.java),
                 )
-            }
+            },
         )
 
         reader.close()