Extension incorrectly runs cached `.class` file from another class of same name with no `package`

Bug report

Suppose there is a file structure:

folder1/
    Main.java
folder2/
    Main.java

// folder1/Main.java
public class Main {
    public static void main(String[] args) {
        System.out.println("Main 1");
    }
}

// folder2/Main.java
public class Main {
    public static void main(String[] args) {
        System.out.println("Main 2");
    }
}

No package statements; the projects are not connected at all.

When folder1/Main.java is run first, it gives the correct output Main 1.
But if folder2/Main.java is then run, it gives the wrong output of Main 1 instead of Main 2; the first built file is run instead.
folder1/Main.java 'shadows' folder2/Main.java, since the class name is the same and there are no package statements.
Another file structure that causes this is ./Main.java, ./folder/Main.java

This bug is inconvenient when multiple different, unrelated Java projects are in the same workspace.

通过运行 folder1/Main.java，然后运行 folder2/Main.java 来重现该问题，同时包括 ./Main.java 和 ./folder/Main.java 的布局。跟踪扩展如何选择缓存的已编译类；完成的标准是每个不相关的 Main.java 都运行其自身的输出，包括在另一个文件已经运行之后。