Sending a short message prompts that java.lang.long cannot be forcibly converted to java.lang.string

For example, as follows, I will let you develop and solve bugs.

List & lt object & gt list = new ArrayList & lt> ();

L =1l;

list . add(l)；

String s =(String)list . get(0)；

Running this code will throw your exception:

Java.lang.ClassCastException: class java.lang.Long cannot be converted into class Java. lang. string (java.lang.long and java.lang.string are located in the java.base module of the loader "bootstrap").