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* The use of `CoroutineContext` and `Clock` as parameters of classes has been replaced 
  by the `Dispatcher` interface.
* The use of `Clock` has been replaced by `InstantSource` which does not carry time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* The use of `Random` and `SplittableRandom` as parameter type has been replaced 
   by `RandomGenerator`

2 files changed, 5 insertions, 5 deletions

diff --git a/opendc-simulator/opendc-simulator-compute/src/main/java/org/opendc/simulator/compute/SimPsuFactories.java b/opendc-simulator/opendc-simulator-compute/src/main/java/org/opendc/simulator/compute/SimPsuFactories.java
index 52d04052..05b40cf8 100644
--- a/opendc-simulator/opendc-simulator-compute/src/main/java/org/opendc/simulator/compute/SimPsuFactories.java
+++ b/opendc-simulator/opendc-simulator-compute/src/main/java/org/opendc/simulator/compute/SimPsuFactories.java
@@ -22,7 +22,7 @@
 
 package org.opendc.simulator.compute;
 
-import java.time.Clock;
+import java.time.InstantSource;
 import org.jetbrains.annotations.NotNull;
 import org.opendc.simulator.compute.model.ProcessingUnit;
 import org.opendc.simulator.compute.power.CpuPowerModel;
@@ -117,7 +117,7 @@ public class SimPsuFactories {
         private final FlowStage stage;
         private final OutPort out;
         private final CpuPowerModel model;
-        private final Clock clock;
+        private final InstantSource clock;
 
         private double targetFreq;
         private double totalUsage;
diff --git a/opendc-simulator/opendc-simulator-compute/src/main/java/org/opendc/simulator/compute/kernel/SimHypervisor.java b/opendc-simulator/opendc-simulator-compute/src/main/java/org/opendc/simulator/compute/kernel/SimHypervisor.java
index 4ebcba71..a1623351 100644
--- a/opendc-simulator/opendc-simulator-compute/src/main/java/org/opendc/simulator/compute/kernel/SimHypervisor.java
+++ b/opendc-simulator/opendc-simulator-compute/src/main/java/org/opendc/simulator/compute/kernel/SimHypervisor.java
@@ -22,7 +22,7 @@
 
 package org.opendc.simulator.compute.kernel;
 
-import java.time.Clock;
+import java.time.InstantSource;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
@@ -253,7 +253,7 @@ public final class SimHypervisor implements SimWorkload {
         private final FlowMultiplexer multiplexer;
         private final FlowStage stage;
         private final List<ScalingGovernor> scalingGovernors;
-        private final Clock clock;
+        private final InstantSource clock;
         private final HvCounters counters;
 
         private long lastCounterUpdate;
@@ -526,7 +526,7 @@ public final class SimHypervisor implements SimWorkload {
         private final VmInterferenceMember interferenceMember;
         private final FlowStage stage;
         private final FlowMultiplexer multiplexer;
-        private final Clock clock;
+        private final InstantSource clock;
 
         private final List<VCpu> cpus;
         private final SimAbstractMachine.Memory memory;