merge: Extract scheduler from simulation coroutine dispatcher (#106)

This pull request extracts the scheduler from the `SimulationCoroutineDispatcher` into 
a separate `SimulationScheduler` class which allows users to re-use the scheduler 
between different coroutine dispatchers.

We implement the `SimulationScheduler` in Java, removing the explicit dependency on 
Kotlin or `kotlinx-coroutines`. The scheduler uses a separate specialized priority queue 
implementation that eliminates allocation in the hot path of the simulator.

## Implementation Notes :hammer_and_pick:

* Add Java-based simulator core
* Use SimulationScheduler in coroutine dispatcher
* Rename runBlockingSimulation to runSimulation

## External Dependencies :four_leaf_clover:

* N/A 

## Breaking API Changes :warning:

* The Kotlin API for simulation has been moved to `org.opendc.simulator.kotlin`.
* `runBlockingSImulation` renamed to `runSimulation`

3 files changed, 20 insertions, 20 deletions

diff --git a/opendc-simulator/opendc-simulator-power/src/test/kotlin/org/opendc/simulator/power/SimPduTest.kt b/opendc-simulator/opendc-simulator-power/src/test/kotlin/org/opendc/simulator/power/SimPduTest.kt
index 7cc4b801..29c50d3f 100644
--- a/opendc-simulator/opendc-simulator-power/src/test/kotlin/org/opendc/simulator/power/SimPduTest.kt
+++ b/opendc-simulator/opendc-simulator-power/src/test/kotlin/org/opendc/simulator/power/SimPduTest.kt
@@ -27,17 +27,17 @@ import io.mockk.verify
 import org.junit.jupiter.api.Assertions.assertEquals
 import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.assertThrows
-import org.opendc.simulator.core.runBlockingSimulation
 import org.opendc.simulator.flow.FlowEngine
 import org.opendc.simulator.flow.FlowSource
 import org.opendc.simulator.flow.source.FixedFlowSource
+import org.opendc.simulator.kotlin.runSimulation
 
 /**
  * Test suite for the [SimPdu] class.
  */
 internal class SimPduTest {
     @Test
-    fun testZeroOutlets() = runBlockingSimulation {
+    fun testZeroOutlets() = runSimulation {
         val engine = FlowEngine(coroutineContext, clock)
         val source = SimPowerSource(engine, capacity = 100.0)
         val pdu = SimPdu(engine)
@@ -47,7 +47,7 @@ internal class SimPduTest {
     }
 
     @Test
-    fun testSingleOutlet() = runBlockingSimulation {
+    fun testSingleOutlet() = runSimulation {
         val engine = FlowEngine(coroutineContext, clock)
         val source = SimPowerSource(engine, capacity = 100.0)
         val pdu = SimPdu(engine)
@@ -58,7 +58,7 @@ internal class SimPduTest {
     }
 
     @Test
-    fun testDoubleOutlet() = runBlockingSimulation {
+    fun testDoubleOutlet() = runSimulation {
         val engine = FlowEngine(coroutineContext, clock)
         val source = SimPowerSource(engine, capacity = 100.0)
         val pdu = SimPdu(engine)
@@ -71,7 +71,7 @@ internal class SimPduTest {
     }
 
     @Test
-    fun testDisconnect() = runBlockingSimulation {
+    fun testDisconnect() = runSimulation {
         val engine = FlowEngine(coroutineContext, clock)
         val source = SimPowerSource(engine, capacity = 100.0)
         val pdu = SimPdu(engine)
@@ -89,7 +89,7 @@ internal class SimPduTest {
     }
 
     @Test
-    fun testLoss() = runBlockingSimulation {
+    fun testLoss() = runSimulation {
         val engine = FlowEngine(coroutineContext, clock)
         val source = SimPowerSource(engine, capacity = 100.0)
         // https://download.schneider-electric.com/files?p_Doc_Ref=SPD_NRAN-66CK3D_EN
@@ -100,7 +100,7 @@ internal class SimPduTest {
     }
 
     @Test
-    fun testOutletClose() = runBlockingSimulation {
+    fun testOutletClose() = runSimulation {
         val engine = FlowEngine(coroutineContext, clock)
         val source = SimPowerSource(engine, capacity = 100.0)
         val pdu = SimPdu(engine)
diff --git a/opendc-simulator/opendc-simulator-power/src/test/kotlin/org/opendc/simulator/power/SimPowerSourceTest.kt b/opendc-simulator/opendc-simulator-power/src/test/kotlin/org/opendc/simulator/power/SimPowerSourceTest.kt
index 4f319e65..b83b6ba7 100644
--- a/opendc-simulator/opendc-simulator-power/src/test/kotlin/org/opendc/simulator/power/SimPowerSourceTest.kt
+++ b/opendc-simulator/opendc-simulator-power/src/test/kotlin/org/opendc/simulator/power/SimPowerSourceTest.kt
@@ -30,17 +30,17 @@ import org.junit.jupiter.api.Assertions.*
 import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.assertDoesNotThrow
 import org.junit.jupiter.api.assertThrows
-import org.opendc.simulator.core.runBlockingSimulation
 import org.opendc.simulator.flow.FlowEngine
 import org.opendc.simulator.flow.FlowSource
 import org.opendc.simulator.flow.source.FixedFlowSource
+import org.opendc.simulator.kotlin.runSimulation
 
 /**
  * Test suite for the [SimPowerSource]
  */
 internal class SimPowerSourceTest {
     @Test
-    fun testInitialState() = runBlockingSimulation {
+    fun testInitialState() = runSimulation {
         val engine = FlowEngine(coroutineContext, clock)
         val source = SimPowerSource(engine, capacity = 100.0)
 
@@ -50,7 +50,7 @@ internal class SimPowerSourceTest {
     }
 
     @Test
-    fun testDisconnectIdempotent() = runBlockingSimulation {
+    fun testDisconnectIdempotent() = runSimulation {
         val engine = FlowEngine(coroutineContext, clock)
         val source = SimPowerSource(engine, capacity = 100.0)
 
@@ -59,7 +59,7 @@ internal class SimPowerSourceTest {
     }
 
     @Test
-    fun testConnect() = runBlockingSimulation {
+    fun testConnect() = runSimulation {
         val engine = FlowEngine(coroutineContext, clock)
         val source = SimPowerSource(engine, capacity = 100.0)
         val inlet = SimpleInlet()
@@ -74,7 +74,7 @@ internal class SimPowerSourceTest {
     }
 
     @Test
-    fun testDisconnect() = runBlockingSimulation {
+    fun testDisconnect() = runSimulation {
         val engine = FlowEngine(coroutineContext, clock)
         val source = SimPowerSource(engine, capacity = 100.0)
         val consumer = spyk(FixedFlowSource(100.0, utilization = 1.0))
@@ -89,7 +89,7 @@ internal class SimPowerSourceTest {
     }
 
     @Test
-    fun testDisconnectAssertion() = runBlockingSimulation {
+    fun testDisconnectAssertion() = runSimulation {
         val engine = FlowEngine(coroutineContext, clock)
         val source = SimPowerSource(engine, capacity = 100.0)
         val inlet = mockk<SimPowerInlet>(relaxUnitFun = true)
@@ -105,7 +105,7 @@ internal class SimPowerSourceTest {
     }
 
     @Test
-    fun testOutletAlreadyConnected() = runBlockingSimulation {
+    fun testOutletAlreadyConnected() = runSimulation {
         val engine = FlowEngine(coroutineContext, clock)
         val source = SimPowerSource(engine, capacity = 100.0)
         val inlet = SimpleInlet()
@@ -119,7 +119,7 @@ internal class SimPowerSourceTest {
     }
 
     @Test
-    fun testInletAlreadyConnected() = runBlockingSimulation {
+    fun testInletAlreadyConnected() = runSimulation {
         val engine = FlowEngine(coroutineContext, clock)
         val source = SimPowerSource(engine, capacity = 100.0)
         val inlet = mockk<SimPowerInlet>(relaxUnitFun = true)
diff --git a/opendc-simulator/opendc-simulator-power/src/test/kotlin/org/opendc/simulator/power/SimUpsTest.kt b/opendc-simulator/opendc-simulator-power/src/test/kotlin/org/opendc/simulator/power/SimUpsTest.kt
index e19e72fa..2b2921d7 100644
--- a/opendc-simulator/opendc-simulator-power/src/test/kotlin/org/opendc/simulator/power/SimUpsTest.kt
+++ b/opendc-simulator/opendc-simulator-power/src/test/kotlin/org/opendc/simulator/power/SimUpsTest.kt
@@ -27,17 +27,17 @@ import io.mockk.verify
 import org.junit.jupiter.api.Assertions.assertAll
 import org.junit.jupiter.api.Assertions.assertEquals
 import org.junit.jupiter.api.Test
-import org.opendc.simulator.core.runBlockingSimulation
 import org.opendc.simulator.flow.FlowEngine
 import org.opendc.simulator.flow.FlowSource
 import org.opendc.simulator.flow.source.FixedFlowSource
+import org.opendc.simulator.kotlin.runSimulation
 
 /**
  * Test suite for the [SimUps] class.
  */
 internal class SimUpsTest {
     @Test
-    fun testSingleInlet() = runBlockingSimulation {
+    fun testSingleInlet() = runSimulation {
         val engine = FlowEngine(coroutineContext, clock)
         val source = SimPowerSource(engine, capacity = 100.0)
         val ups = SimUps(engine)
@@ -48,7 +48,7 @@ internal class SimUpsTest {
     }
 
     @Test
-    fun testDoubleInlet() = runBlockingSimulation {
+    fun testDoubleInlet() = runSimulation {
         val engine = FlowEngine(coroutineContext, clock)
         val source1 = SimPowerSource(engine, capacity = 100.0)
         val source2 = SimPowerSource(engine, capacity = 100.0)
@@ -65,7 +65,7 @@ internal class SimUpsTest {
     }
 
     @Test
-    fun testLoss() = runBlockingSimulation {
+    fun testLoss() = runSimulation {
         val engine = FlowEngine(coroutineContext, clock)
         val source = SimPowerSource(engine, capacity = 100.0)
         // https://download.schneider-electric.com/files?p_Doc_Ref=SPD_NRAN-66CK3D_EN
@@ -77,7 +77,7 @@ internal class SimUpsTest {
     }
 
     @Test
-    fun testDisconnect() = runBlockingSimulation {
+    fun testDisconnect() = runSimulation {
         val engine = FlowEngine(coroutineContext, clock)
         val source1 = SimPowerSource(engine, capacity = 100.0)
         val source2 = SimPowerSource(engine, capacity = 100.0)