Adds JNI Simulator interface and updated Sim API (#1002)

The simulator was generated by https://github.com/ThadHouse/SimulatorGenerator

wpilibj/src/test/java/edu/wpi/first/wpilibj/sim/AnalogInputSimTest.java

@@ -0,0 +1,47 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) 2018 FIRST. All Rights Reserved.                             */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+package edu.wpi.first.wpilibj.sim;
+
+import static org.junit.Assert.assertEquals;
+
+import org.junit.Test;
+
+import edu.wpi.first.wpilibj.AnalogInput;
+import edu.wpi.first.wpilibj.hal.HAL;
+
+public class AnalogInputSimTest {
+  static class DoubleStore {
+    public boolean wasTriggered = false;
+    public boolean wasCorrectType = false;
+    public double setValue = 0;
+  }
+
+  @Test
+  public void testSetCallback() {
+    HAL.initialize(500, 0);
+
+
+    AnalogInput input = new AnalogInput(5);
+
+    AnalogInSim inputSim = input.getSimObject();
+
+    for (double i = 0; i < 5.0; i+=0.1) {
+      inputSim.setVoltage(0);
+
+      assertEquals(input.getVoltage(), 0, 0.001);
+
+      inputSim.setVoltage(i);
+
+      assertEquals(input.getVoltage(), i, 0.001);
+
+    }
+
+
+
+  }
+}

wpilibj/src/test/java/edu/wpi/first/wpilibj/sim/AnalogOutputSimTest.java

@@ -0,0 +1,69 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) 2018 FIRST. All Rights Reserved.                             */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+package edu.wpi.first.wpilibj.sim;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+import org.junit.Test;
+
+import edu.wpi.first.wpilibj.AnalogOutput;
+import edu.wpi.first.wpilibj.hal.HAL;
+
+public class AnalogOutputSimTest {
+  static class DoubleStore {
+    public boolean wasTriggered = false;
+    public boolean wasCorrectType = false;
+    public double setValue = -1;
+
+    public void reset() {
+      wasCorrectType = false;
+      wasTriggered = false;
+      setValue = -1;
+    }
+  }
+
+  @Test
+  public void testSetCallback() {
+    HAL.initialize(500, 0);
+
+
+    AnalogOutput output = new AnalogOutput(0);
+    output.setVoltage(0.5);
+
+    AnalogOutSim outputSim = output.getSimObject();
+
+    DoubleStore store = new DoubleStore();
+
+    try (CallbackStore cb = outputSim.registerVoltageCallback((s, v) -> {
+      store.wasTriggered = true;
+      store.wasCorrectType = true;
+      store.setValue = v.getDouble();
+    }, false)) {
+      assertFalse(store.wasTriggered);
+
+      for (double i = 0.1; i < 5.0; i+=0.1) {
+        store.reset();
+
+        output.setVoltage(0);
+
+        assertTrue(store.wasTriggered);
+        assertEquals(store.setValue, 0, 0.001);
+
+        store.reset();
+
+        output.setVoltage(i);
+
+        assertTrue(store.wasTriggered);
+        assertEquals(store.setValue, i, 0.001);
+
+      }
+    }
+  }
+}