只需将文件直接移动到调用 Java 的项目文件夹(以及您制作的蓝色模糊条纹下的东西:P).

Just move the file directly to the project folder which calls Java (and something under the blue-blurred stripe you made :P).

如果这没有帮助，则将 test123.txt 文件移动到 FirstJavaProgram 目录.

If that doesn't help, then move the test123.txt file to FirstJavaProgram directory.

您还可以将文件名更改为以下之一:

You can also change filename to one of these:

1. src/test123.txt

FirstJavaProgram/src/test123.txt

我不确定哪一个适合你的情况.

I am not sure which one will be fine in your case.