Improve equals contract in Nucleus (#316)

* Update equals and hashCode in ActorId and corresponding tests

* Update equals and hashCode in DataManagerId and corresponding tests

* Update equals and hashCode in ReportId and corresponding tests

* Update equals and hashCode in SimplePluginId and corresponding tests

* Update equals and hashCode in SimulationState and corresponding tests

* Update equals and hashCode in AT_ActorContext

* Update equals and hashCode in TestScenarioReport and corresponding tests

* Update equals and hashCode in RunContinuityPluginData and corresponding tests

* Update equals and hashCode in ExperimentParameterData and corresponding tests

* Update equals and hashCode in FunctionalDimensionData and corresponding tests

* Update equals and hashCode in IdentifiableFunction and corresponding tests

* Update equals and hashCode in TestReportPlan and corresponding tests

* Update equals and hashCode in TestDataManagerPlan and corresponding tests

* Update equals and hashCode in TestActorPlan and corresponding tests

* Update equals and hashCode for TestDimensionData in AT_DimensionData

* Update equals and hashCode in Plugin and corresponding tests

* Update equals and hashCode in TestPluginData and corresponding tests

* Minor updates and typo corrections

---------

Co-authored-by: shawnhatch <hatchs@leidos.com>

Author: travisrieglerleidos

simulation/src/main/java/gov/hhs/aspr/ms/gcm/simulation/nucleus/ActorId.java

@@ -1,5 +1,7 @@
 package gov.hhs.aspr.ms.gcm.simulation.nucleus;
 
+import java.util.Objects;
+
 /**
  * The unique identifier for actors. Actors are constructed dynamically and ids
  * are distributed contiguously from 0.
@@ -35,31 +37,29 @@ public String toString() {
 	}
 
 	/**
-	 * Standard hash code implementation
-	 */
+     * Standard implementation consistent with the {@link #equals(Object)} method
+     */
 	@Override
 	public int hashCode() {
-		final int prime = 31;
-		int result = 1;
-		result = prime * result + id;
-		return result;
+		return Objects.hash(id);
 	}
 
 	/**
-	 * Actor Id instances are equal if and only if their values are equal
-	 */
+     * Two {@link ActorId} instances are equal if and only if
+     * their inputs are equal.
+     */
 	@Override
 	public boolean equals(Object obj) {
-		if (this == obj)
+		if (this == obj) {
 			return true;
-		if (obj == null)
+		}
+		if (obj == null) {
 			return false;
-		if (getClass() != obj.getClass())
+		}
+		if (getClass() != obj.getClass()) {
 			return false;
+		}
 		ActorId other = (ActorId) obj;
-		if (id != other.id)
-			return false;
-		return true;
+		return id == other.id;
 	}
-
 }

simulation/src/main/java/gov/hhs/aspr/ms/gcm/simulation/nucleus/DataManagerId.java

@@ -1,5 +1,7 @@
 package gov.hhs.aspr.ms.gcm.simulation.nucleus;
 
+import java.util.Objects;
+
 /**
  * The unique identifier for data managers. DataManagerId values are constructed
  * dynamically and are distributed contiguously from 0.
@@ -22,32 +24,30 @@ public final int getValue() {
 	}
 
 	/**
-	 * Standard hash code implementation
-	 */
+     * Standard implementation consistent with the {@link #equals(Object)} method
+     */
 	@Override
 	public int hashCode() {
-		final int prime = 31;
-		int result = 1;
-		result = prime * result + id;
-		return result;
+		return Objects.hash(id);
 	}
 
 	/**
-	 * DataManagerId instances are equal if and only if their values are equal
-	 */
+     * Two {@link DataManagerId} instances are equal if and only if
+     * their inputs are equal.
+     */
 	@Override
 	public boolean equals(Object obj) {
 		if (this == obj) {
 			return true;
 		}
-		if (!(obj instanceof DataManagerId)) {
+		if (obj == null) {
 			return false;
 		}
-		DataManagerId other = (DataManagerId) obj;
-		if (id != other.id) {
+		if (getClass() != obj.getClass()) {
 			return false;
 		}
-		return true;
+		DataManagerId other = (DataManagerId) obj;
+		return id == other.id;
 	}
 
 	/**

simulation/src/main/java/gov/hhs/aspr/ms/gcm/simulation/nucleus/ExperimentParameterData.java

@@ -170,61 +170,38 @@ private Data(Data data) {
 			locked = data.locked;
 		}
 
+		/**
+		 * Standard implementation consistent with the {@link #equals(Object)} method
+		 */
 		@Override
 		public int hashCode() {
-			final int prime = 31;
-			int result = 1;
-			result = prime * result + (continueFromProgressLog ? 1231 : 1237);
-			result = prime * result + ((experimentProgressLogPath == null) ? 0 : experimentProgressLogPath.hashCode());
-			result = prime * result + ((explicitScenarioIds == null) ? 0 : explicitScenarioIds.hashCode());
-			result = prime * result + (haltOnException ? 1231 : 1237);
-			result = prime * result + ((simulationHaltTime == null) ? 0 : simulationHaltTime.hashCode());
-			result = prime * result + (stateRecordingIsScheduled ? 1231 : 1237);
-			result = prime * result + threadCount;
-			return result;
+			return Objects.hash(threadCount, stateRecordingIsScheduled, simulationHaltTime, haltOnException,
+					experimentProgressLogPath, continueFromProgressLog, explicitScenarioIds);
 		}
 
+		/**
+		 * Two {@link Data} instances are equal if and only if
+		 * their inputs are equal.
+		 */
 		@Override
 		public boolean equals(Object obj) {
 			if (this == obj) {
 				return true;
 			}
-			if (!(obj instanceof Data)) {
-				return false;
-			}
-			Data other = (Data) obj;
-			if (continueFromProgressLog != other.continueFromProgressLog) {
-				return false;
-			}
-			if (experimentProgressLogPath == null) {
-				if (other.experimentProgressLogPath != null) {
-					return false;
-				}
-			} else if (!experimentProgressLogPath.equals(other.experimentProgressLogPath)) {
-				return false;
-			}
-			if (!explicitScenarioIds.equals(other.explicitScenarioIds)) {
-				return false;
-			}
-			if (haltOnException != other.haltOnException) {
-				return false;
-			}
-			if (simulationHaltTime == null) {
-				if (other.simulationHaltTime != null) {
-					return false;
-				}
-			} else if (!simulationHaltTime.equals(other.simulationHaltTime)) {
+			if (obj == null) {
 				return false;
 			}
-			if (stateRecordingIsScheduled != other.stateRecordingIsScheduled) {
+			if (getClass() != obj.getClass()) {
 				return false;
 			}
-			if (threadCount != other.threadCount) {
-				return false;
-			}
-			return true;
+			Data other = (Data) obj;
+			return threadCount == other.threadCount && stateRecordingIsScheduled == other.stateRecordingIsScheduled
+					&& Objects.equals(simulationHaltTime, other.simulationHaltTime)
+					&& haltOnException == other.haltOnException
+					&& Objects.equals(experimentProgressLogPath, other.experimentProgressLogPath)
+					&& continueFromProgressLog == other.continueFromProgressLog
+					&& Objects.equals(explicitScenarioIds, other.explicitScenarioIds);
 		}
-
 	}
 
 	/**
@@ -316,11 +293,18 @@ public static boolean checkVersionSupported(String version) {
 		return StandardVersioning.checkVersionSupported(version);
 	}
 
+	/**
+	 * Standard implementation consistent with the {@link #equals(Object)} method
+	 */
 	@Override
 	public int hashCode() {
 		return Objects.hash(data);
 	}
 
+	/**
+	 * Two {@link ExperimentParameterData} instances are equal if and only if
+	 * their inputs are equal.
+	 */
 	@Override
 	public boolean equals(Object obj) {
 		if (this == obj) {

simulation/src/main/java/gov/hhs/aspr/ms/gcm/simulation/nucleus/FunctionalDimensionData.java

@@ -5,6 +5,7 @@
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 import java.util.function.Function;
 
 import gov.hhs.aspr.ms.util.errors.ContractException;
@@ -166,16 +167,18 @@ private Data(Data data) {
             locked = data.locked;
         }
 
+        /**
+         * Standard implementation consistent with the {@link #equals(Object)} method
+         */
         @Override
         public int hashCode() {
-            final int prime = 31;
-            int result = 1;
-            result = prime * result + ((levelNames == null) ? 0 : levelNames.hashCode());
-            result = prime * result + ((values == null) ? 0 : values.hashCode());
-            result = prime * result + ((metaData == null) ? 0 : metaData.hashCode());
-            return result;
+            return Objects.hash(levelNames, values, metaData);
         }
 
+        /**
+         * Two {@link Data} instances are equal if and only if
+         * their inputs are equal.
+         */
         @Override
         public boolean equals(Object obj) {
             if (this == obj) {
@@ -188,22 +191,8 @@ public boolean equals(Object obj) {
                 return false;
             }
             Data other = (Data) obj;
-            if (levelNames == null) {
-                if (other.levelNames != null)
-                    return false;
-            } else if (!levelNames.equals(other.levelNames))
-                return false;
-            if (values == null) {
-                if (other.values != null)
-                    return false;
-            } else if (!values.equals(other.values))
-                return false;
-            if (metaData == null) {
-                if (other.metaData != null)
-                    return false;
-            } else if (!metaData.equals(other.metaData))
-                return false;
-            return true;
+            return Objects.equals(levelNames, other.levelNames) && Objects.equals(values, other.values)
+                    && Objects.equals(metaData, other.metaData);
         }
 
         @Override
@@ -271,29 +260,31 @@ public static boolean checkVersionSupported(String version) {
         return StandardVersioning.checkVersionSupported(version);
     }
 
+    /**
+     * Standard implementation consistent with the {@link #equals(Object)} method
+     */
     @Override
     public int hashCode() {
-        final int prime = 31;
-        int result = 1;
-        result = prime * result + ((data == null) ? 0 : data.hashCode());
-        return result;
+        return Objects.hash(data);
     }
 
+    /**
+     * Two {@link FunctionalDimensionData} instances are equal if and only if
+     * their inputs are equal.
+     */
     @Override
     public boolean equals(Object obj) {
-        if (this == obj)
+        if (this == obj) {
             return true;
-        if (obj == null)
+        }
+        if (obj == null) {
             return false;
-        if (getClass() != obj.getClass())
+        }
+        if (getClass() != obj.getClass()) {
             return false;
+        }
         FunctionalDimensionData other = (FunctionalDimensionData) obj;
-        if (data == null) {
-            if (other.data != null)
-                return false;
-        } else if (!data.equals(other.data))
-            return false;
-        return true;
+        return Objects.equals(data, other.data);
     }
 
     @Override

simulation/src/main/java/gov/hhs/aspr/ms/gcm/simulation/nucleus/IdentifiableFunction.java

@@ -1,5 +1,6 @@
 package gov.hhs.aspr.ms.gcm.simulation.nucleus;
 
+import java.util.Objects;
 import java.util.function.Function;
 
 import gov.hhs.aspr.ms.util.errors.ContractException;
@@ -26,31 +27,30 @@ public Function<N, Object> getFunction() {
 		return function;
 	}
 
+	/**
+	 * Standard implementation consistent with the {@link #equals(Object)} method
+	 */
 	@Override
 	public int hashCode() {
-		final int prime = 31;
-		int result = 1;
-		result = prime * result + ((functionId == null) ? 0 : functionId.hashCode());
-		return result;
+		return Objects.hash(functionId);
 	}
 
+	/**
+	 * Two {@link IdentifiableFunction} instances are equal if and only if
+	 * their functionIds are equal.
+	 */
 	@Override
 	public boolean equals(Object obj) {
 		if (this == obj) {
 			return true;
 		}
-		if (!(obj instanceof IdentifiableFunction)) {
+		if (obj == null) {
 			return false;
 		}
-		IdentifiableFunction<?> other = (IdentifiableFunction<?>) obj;
-		if (functionId == null) {
-			if (other.functionId != null) {
-				return false;
-			}
-		} else if (!functionId.equals(other.functionId)) {
+		if (getClass() != obj.getClass()) {
 			return false;
 		}
-		return true;
+		IdentifiableFunction<?> other = (IdentifiableFunction<?>) obj;
+		return Objects.equals(functionId, other.functionId);
 	}
-
 }