ArrayList get(int) Object Error

Error produced in debugger
Breakpoint condition 'test.get(0).get(0).equals("Work0")' error: Cannot evaluate because of compilation error(s): The method get(int) is undefined for the type Object.

Breakpoint created on line with System.out.println("End") used in debugger
test.get(0).get(0).equals("Work0")

Consolidated code
import java.util.ArrayList;

public class ArrayList2D {
public static void main(String[] args) {
ArrayList<ArrayList> test = new ArrayList<ArrayList>();
ArrayList subTest = new ArrayList();
subTest.add("Work0");
subTest.add("Work1");
subTest.add("Work2");
test.add(subTest);
System.out.println("Full ArrayList: " + test);
System.out.println("Targetted location of ArrayList: " + test.get(0).get(0));
if (test.get(0).get(0).equals("Work0")) {
System.out.println("Breakpoint should work!");
}
System.out.println("End");
}
}

Code Output without Debugger
Full ArrayList: [[Work0, Work1, Work2]]
Targetted location of ArrayList: Work0
Breakpoint should work!
End

Environment

• Operating System: Windows 10 x64
• JDK version: JDK 13.0.2
• Visual Studio Code version: 1.51.1
• Java extension version: 0.12.0
• Java Debugger extension version: 0.29.0

Steps To Reproduce

1. Run consolidated code
2. Setup a breakpoint at the End printout with test.get(0).get(0).equals("Work0")

Current Result

test.get(0).get(0): Cannot evaluate because of compilation error(s): The method get(int) is undefined for the type Object.

Expected Result

test.get(0).get(0): "Work0"

Additional Information

I have a program that uses 2D ArrayLists, and I commonly will track down issues utilizing the debugger. I have not used the debugger in a few months, but since I came back to my setup (same breakpoints as before) the debugger has changed behavior.

首先使用整合后的 ArrayList2D 代码、JDK 13.0.2 和 Java Debugger 扩展重现该问题，然后跟踪调试器对 test.get(0).get(0) 的条件表达式求值过程。当断点条件成功求值并显示 "Work0"，而不是报告 get(int) 对 Object 未定义时，该 Issue 即完成。