[hal] Add method to detect if the CAN Stream has overflowed (#6105)

hal/src/main/java/edu/wpi/first/hal/can/CANJNI.java

@@ -31,5 +31,6 @@ public class CANJNI extends JNIWrapper {
   public static native void closeCANStreamSession(int sessionHandle);
 
   public static native int readCANStreamSession(
-      int sessionHandle, CANStreamMessage[] messages, int messagesToRead);
+      int sessionHandle, CANStreamMessage[] messages, int messagesToRead)
+      throws CANStreamOverflowException;
 }

hal/src/main/java/edu/wpi/first/hal/can/CANStreamOverflowException.java

@@ -0,0 +1,35 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+package edu.wpi.first.hal.can;
+
+import edu.wpi.first.hal.CANStreamMessage;
+import java.io.IOException;
+
+public class CANStreamOverflowException extends IOException {
+  private final CANStreamMessage[] m_messages;
+  private final int m_messagesRead;
+
+  /**
+   * Constructs a new CANStreamOverflowException.
+   *
+   * @param messages The messages
+   * @param messagesRead The length of messages read
+   */
+  @SuppressWarnings("PMD.ArrayIsStoredDirectly")
+  public CANStreamOverflowException(CANStreamMessage[] messages, int messagesRead) {
+    super("A CAN Stream has overflowed. Data will be missed");
+    this.m_messages = messages;
+    this.m_messagesRead = messagesRead;
+  }
+
+  @SuppressWarnings("PMD.MethodReturnsInternalArray")
+  public CANStreamMessage[] getMessages() {
+    return m_messages;
+  }
+
+  public int getMessagesRead() {
+    return m_messagesRead;
+  }
+}