merge: Increase minimum Java version to 17 (#115)

This pull request increases the minimum version of Java required by OpenDC to 17.
This new version of Java introduces several new features compared to our old minimum 
version (11), which we attempt to apply in this conversion.

## Implementation Notes :hammer_and_pick:

* Increase minimum Java version to Java 17 
* Use RandomGenerator as randomness source 
* Add common dispatcher interface 
* Add compatibility with Kotlin coroutines
* Use InstantSource as time source
* Re-implement SimulationScheduler as Dispatcher 
* Replace use of CoroutineContext by Dispatcher 

## External Dependencies :four_leaf_clover:

* Java 17

## Breaking API Changes :warning:

* The use of `CoroutineContext` and `Clock` as parameters of classes has been replaced 
  by the `Dispatcher` interface.
* The use of `Clock` has been replaced by `InstantSource` which does not carry time
   zone info.
* The use of `Random` and `SplittableRandom` as parameter type has been replaced 
   by `RandomGenerator`

4 files changed, 18 insertions, 17 deletions

diff --git a/opendc-experiments/opendc-experiments-capelin/src/jmh/kotlin/org/opendc/experiments/capelin/CapelinBenchmarks.kt b/opendc-experiments/opendc-experiments-capelin/src/jmh/kotlin/org/opendc/experiments/capelin/CapelinBenchmarks.kt
index 3e3d758d..1221f084 100644
--- a/opendc-experiments/opendc-experiments-capelin/src/jmh/kotlin/org/opendc/experiments/capelin/CapelinBenchmarks.kt
+++ b/opendc-experiments/opendc-experiments-capelin/src/jmh/kotlin/org/opendc/experiments/capelin/CapelinBenchmarks.kt
@@ -75,7 +75,7 @@ class CapelinBenchmarks {
     fun benchmarkCapelin() = runSimulation {
         val serviceDomain = "compute.opendc.org"
 
-        Provisioner(coroutineContext, clock, seed = 0).use { provisioner ->
+        Provisioner(dispatcher, seed = 0).use { provisioner ->
             val computeScheduler = FilterScheduler(
                 filters = listOf(ComputeFilter(), VCpuFilter(16.0), RamFilter(1.0)),
                 weighers = listOf(CoreRamWeigher(multiplier = 1.0))
@@ -87,7 +87,7 @@ class CapelinBenchmarks {
             )
 
             val service = provisioner.registry.resolve(serviceDomain, ComputeService::class.java)!!
-            service.replay(clock, vms, 0L, interference = true)
+            service.replay(timeSource, vms, 0L, interference = true)
         }
     }
 }
diff --git a/opendc-experiments/opendc-experiments-capelin/src/main/kotlin/org/opendc/experiments/capelin/CapelinRunner.kt b/opendc-experiments/opendc-experiments-capelin/src/main/kotlin/org/opendc/experiments/capelin/CapelinRunner.kt
index 2c3573dc..2567a4d5 100644
--- a/opendc-experiments/opendc-experiments-capelin/src/main/kotlin/org/opendc/experiments/capelin/CapelinRunner.kt
+++ b/opendc-experiments/opendc-experiments-capelin/src/main/kotlin/org/opendc/experiments/capelin/CapelinRunner.kt
@@ -64,7 +64,7 @@ public class CapelinRunner(
         val serviceDomain = "compute.opendc.org"
         val topology = clusterTopology(File(envPath, "${scenario.topology.name}.txt"))
 
-        Provisioner(coroutineContext, clock, seed).use { provisioner ->
+        Provisioner(dispatcher, seed).use { provisioner ->
             provisioner.runSteps(
                 setupComputeService(serviceDomain, { createComputeScheduler(scenario.allocationPolicy, Random(it.seeder.nextLong())) }),
                 setupHosts(serviceDomain, topology, optimize = true)
@@ -96,7 +96,7 @@ public class CapelinRunner(
                     null
                 }
 
-            service.replay(clock, vms, seed, failureModel = failureModel, interference = operationalPhenomena.hasInterference)
+            service.replay(timeSource, vms, seed, failureModel = failureModel, interference = operationalPhenomena.hasInterference)
         }
     }
 }
diff --git a/opendc-experiments/opendc-experiments-capelin/src/main/kotlin/org/opendc/experiments/capelin/topology/TopologyFactories.kt b/opendc-experiments/opendc-experiments-capelin/src/main/kotlin/org/opendc/experiments/capelin/topology/TopologyFactories.kt
index 0b4cafa6..3a2acbd7 100644
--- a/opendc-experiments/opendc-experiments-capelin/src/main/kotlin/org/opendc/experiments/capelin/topology/TopologyFactories.kt
+++ b/opendc-experiments/opendc-experiments-capelin/src/main/kotlin/org/opendc/experiments/capelin/topology/TopologyFactories.kt
@@ -34,8 +34,9 @@ import org.opendc.simulator.compute.power.CpuPowerModel
 import org.opendc.simulator.compute.power.CpuPowerModels
 import java.io.File
 import java.io.InputStream
-import java.util.Random
+import java.util.SplittableRandom
 import java.util.UUID
+import java.util.random.RandomGenerator
 import kotlin.math.roundToLong
 
 /**
@@ -49,7 +50,7 @@ private val reader = ClusterSpecReader()
 fun clusterTopology(
     file: File,
     powerModel: CpuPowerModel = CpuPowerModels.linear(350.0, 200.0),
-    random: Random = Random(0)
+    random: RandomGenerator = SplittableRandom(0)
 ): List<HostSpec> {
     return clusterTopology(reader.read(file), powerModel, random)
 }
@@ -60,7 +61,7 @@ fun clusterTopology(
 fun clusterTopology(
     input: InputStream,
     powerModel: CpuPowerModel = CpuPowerModels.linear(350.0, 200.0),
-    random: Random = Random(0)
+    random: RandomGenerator = SplittableRandom(0)
 ): List<HostSpec> {
     return clusterTopology(reader.read(input), powerModel, random)
 }
@@ -68,14 +69,14 @@ fun clusterTopology(
 /**
  * Construct a topology from the given list of [clusters].
  */
-fun clusterTopology(clusters: List<ClusterSpec>, powerModel: CpuPowerModel, random: Random = Random(0)): List<HostSpec> {
+fun clusterTopology(clusters: List<ClusterSpec>, powerModel: CpuPowerModel, random: RandomGenerator = SplittableRandom(0)): List<HostSpec> {
     return clusters.flatMap { it.toHostSpecs(random, powerModel) }
 }
 
 /**
  * Helper method to convert a [ClusterSpec] into a list of [HostSpec]s.
  */
-private fun ClusterSpec.toHostSpecs(random: Random, powerModel: CpuPowerModel): List<HostSpec> {
+private fun ClusterSpec.toHostSpecs(random: RandomGenerator, powerModel: CpuPowerModel): List<HostSpec> {
     val cpuSpeed = cpuSpeed
     val memoryPerHost = memCapacityPerHost.roundToLong()
 
diff --git a/opendc-experiments/opendc-experiments-capelin/src/test/kotlin/org/opendc/experiments/capelin/CapelinIntegrationTest.kt b/opendc-experiments/opendc-experiments-capelin/src/test/kotlin/org/opendc/experiments/capelin/CapelinIntegrationTest.kt
index 77b0d09f..7e01bb64 100644
--- a/opendc-experiments/opendc-experiments-capelin/src/test/kotlin/org/opendc/experiments/capelin/CapelinIntegrationTest.kt
+++ b/opendc-experiments/opendc-experiments-capelin/src/test/kotlin/org/opendc/experiments/capelin/CapelinIntegrationTest.kt
@@ -94,7 +94,7 @@ class CapelinIntegrationTest {
         val topology = createTopology()
         val monitor = monitor
 
-        Provisioner(coroutineContext, clock, seed).use { provisioner ->
+        Provisioner(dispatcher, seed).use { provisioner ->
             provisioner.runSteps(
                 setupComputeService(serviceDomain = "compute.opendc.org", { computeScheduler }),
                 registerComputeMonitor(serviceDomain = "compute.opendc.org", monitor),
@@ -102,7 +102,7 @@ class CapelinIntegrationTest {
             )
 
             val service = provisioner.registry.resolve("compute.opendc.org", ComputeService::class.java)!!
-            service.replay(clock, workload, seed)
+            service.replay(timeSource, workload, seed)
         }
 
         println(
@@ -138,7 +138,7 @@ class CapelinIntegrationTest {
         val topology = createTopology("single")
         val monitor = monitor
 
-        Provisioner(coroutineContext, clock, seed).use { provisioner ->
+        Provisioner(dispatcher, seed).use { provisioner ->
             provisioner.runSteps(
                 setupComputeService(serviceDomain = "compute.opendc.org", { computeScheduler }),
                 registerComputeMonitor(serviceDomain = "compute.opendc.org", monitor),
@@ -146,7 +146,7 @@ class CapelinIntegrationTest {
             )
 
             val service = provisioner.registry.resolve("compute.opendc.org", ComputeService::class.java)!!
-            service.replay(clock, workload, seed)
+            service.replay(timeSource, workload, seed)
         }
 
         println(
@@ -177,7 +177,7 @@ class CapelinIntegrationTest {
         val workload = createTestWorkload(1.0, seed)
         val topology = createTopology("single")
 
-        Provisioner(coroutineContext, clock, seed).use { provisioner ->
+        Provisioner(dispatcher, seed).use { provisioner ->
             provisioner.runSteps(
                 setupComputeService(serviceDomain = "compute.opendc.org", { computeScheduler }),
                 registerComputeMonitor(serviceDomain = "compute.opendc.org", monitor),
@@ -185,7 +185,7 @@ class CapelinIntegrationTest {
             )
 
             val service = provisioner.registry.resolve("compute.opendc.org", ComputeService::class.java)!!
-            service.replay(clock, workload, seed, interference = true)
+            service.replay(timeSource, workload, seed, interference = true)
         }
 
         println(
@@ -216,7 +216,7 @@ class CapelinIntegrationTest {
         val workload = createTestWorkload(0.25, seed)
         val monitor = monitor
 
-        Provisioner(coroutineContext, clock, seed).use { provisioner ->
+        Provisioner(dispatcher, seed).use { provisioner ->
             provisioner.runSteps(
                 setupComputeService(serviceDomain = "compute.opendc.org", { computeScheduler }),
                 registerComputeMonitor(serviceDomain = "compute.opendc.org", monitor),
@@ -224,7 +224,7 @@ class CapelinIntegrationTest {
             )
 
             val service = provisioner.registry.resolve("compute.opendc.org", ComputeService::class.java)!!
-            service.replay(clock, workload, seed, failureModel = grid5000(Duration.ofDays(7)))
+            service.replay(timeSource, workload, seed, failureModel = grid5000(Duration.ofDays(7)))
         }
 
         // Note that these values have been verified beforehand