merge: Add support for trace writing

This pull request extends the trace API to support writing new traces.

- Unify columns of different tables 
- Support column lookup via index
- Use index lookup in trace loader 
- Add property for describing partition keys
- Simplify TraceFormat SPI interface
- Add support for writing traces

**Breaking API Changes**

- `TraceFormat` SPI interface has been redesigned.

2 files changed, 111 insertions, 0 deletions

diff --git a/opendc-trace/opendc-trace-api/src/main/kotlin/org/opendc/trace/internal/TableImpl.kt b/opendc-trace/opendc-trace-api/src/main/kotlin/org/opendc/trace/internal/TableImpl.kt
new file mode 100644
index 00000000..24551edb
--- /dev/null
+++ b/opendc-trace/opendc-trace-api/src/main/kotlin/org/opendc/trace/internal/TableImpl.kt
@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2021 AtLarge Research
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package org.opendc.trace.internal
+
+import org.opendc.trace.Table
+import org.opendc.trace.TableColumn
+import org.opendc.trace.TableReader
+import org.opendc.trace.TableWriter
+import java.util.*
+
+/**
+ * Internal implementation of [Table].
+ */
+internal class TableImpl(val trace: TraceImpl, override val name: String) : Table {
+    /**
+     * The details of this table.
+     */
+    private val details = trace.format.getDetails(trace.path, name)
+
+    override val columns: List<TableColumn<*>>
+        get() = details.columns
+
+    override val partitionKeys: List<TableColumn<*>>
+        get() = details.partitionKeys
+
+    override fun newReader(): TableReader = trace.format.newReader(trace.path, name)
+
+    override fun newWriter(): TableWriter = trace.format.newWriter(trace.path, name)
+
+    override fun toString(): String = "Table[name=$name]"
+
+    override fun hashCode(): Int = Objects.hash(trace, name)
+
+    override fun equals(other: Any?): Boolean = other is TableImpl && trace == other.trace && name == other.name
+}
diff --git a/opendc-trace/opendc-trace-api/src/main/kotlin/org/opendc/trace/internal/TraceImpl.kt b/opendc-trace/opendc-trace-api/src/main/kotlin/org/opendc/trace/internal/TraceImpl.kt
new file mode 100644
index 00000000..fd9536ab
--- /dev/null
+++ b/opendc-trace/opendc-trace-api/src/main/kotlin/org/opendc/trace/internal/TraceImpl.kt
@@ -0,0 +1,56 @@
+/*
+ * Copyright (c) 2021 AtLarge Research
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package org.opendc.trace.internal
+
+import org.opendc.trace.Table
+import org.opendc.trace.Trace
+import org.opendc.trace.spi.TraceFormat
+import java.nio.file.Path
+import java.util.*
+import java.util.concurrent.ConcurrentHashMap
+
+/**
+ * Internal implementation of the [Trace] interface.
+ */
+internal class TraceImpl(val format: TraceFormat, val path: Path) : Trace {
+    /**
+     * A map containing the [TableImpl] instances associated with the trace.
+     */
+    private val tableMap = ConcurrentHashMap<String, TableImpl>()
+
+    override val tables: List<String> = format.getTables(path)
+
+    init {
+        for (table in tables) {
+            tableMap.computeIfAbsent(table) { TableImpl(this, it) }
+        }
+    }
+
+    override fun containsTable(name: String): Boolean = tableMap.containsKey(name)
+
+    override fun getTable(name: String): Table? = tableMap[name]
+
+    override fun hashCode(): Int = Objects.hash(format, path)
+
+    override fun equals(other: Any?): Boolean = other is TraceImpl && format == other.format && path == other.path
+}