From 45b766a5dc0820f7fb6ff7d940f1fd322f8844e7 Mon Sep 17 00:00:00 2001
From: Thad House <ThadHouse@users.noreply.github.com>
Date: Mon, 7 Oct 2019 20:45:33 -0700
Subject: [PATCH] Fix main thread ID being potentially incorrect for simulation
 (#1923)

---
 .../src/main/java/edu/wpi/first/wpilibj/RobotBase.java   | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/wpilibj/src/main/java/edu/wpi/first/wpilibj/RobotBase.java b/wpilibj/src/main/java/edu/wpi/first/wpilibj/RobotBase.java
index c541f9a578..b40e1b862e 100644
--- a/wpilibj/src/main/java/edu/wpi/first/wpilibj/RobotBase.java
+++ b/wpilibj/src/main/java/edu/wpi/first/wpilibj/RobotBase.java
@@ -38,7 +38,7 @@ public abstract class RobotBase implements AutoCloseable {
    * The ID of the main Java thread.
    */
   // This is usually 1, but it is best to make sure
-  public static final long MAIN_THREAD_ID = Thread.currentThread().getId();
+  private static long m_threadId = -1;
 
   private static void setupCameraServerShared() {
     CameraServerShared shared = new CameraServerShared() {
@@ -65,7 +65,7 @@ public abstract class RobotBase implements AutoCloseable {
 
       @Override
       public Long getRobotMainThreadId() {
-        return MAIN_THREAD_ID;
+        return RobotBase.getMainThreadId();
       }
 
       @Override
@@ -90,6 +90,7 @@ public abstract class RobotBase implements AutoCloseable {
    */
   protected RobotBase() {
     NetworkTableInstance inst = NetworkTableInstance.getDefault();
+    m_threadId = Thread.currentThread().getId();
     setupCameraServerShared();
     inst.setNetworkIdentity("Robot");
     inst.startServer("/home/lvuser/networktables.ini");
@@ -100,6 +101,10 @@ public abstract class RobotBase implements AutoCloseable {
     Shuffleboard.disableActuatorWidgets();
   }
 
+  public static long getMainThreadId() {
+    return m_threadId;
+  }
+
   @Deprecated
   public void free() {
   }