Programming VIP

This is actually an online bug I encountered. I share it with you here. If you use reflection, it's very simple. After all, generics are only constrained at compile time and can't do anything at run time. Think about it, if you don't use reflection, is there any way to do it? Cause of problem In the actual business of our company, there is a co ...

Problem discovery At 9 a.m. on January 21, 2022, a large area of "system unknown error" was reported in the order system, resulting in some users unable to place orders normally. Query the background log and you can see a large number of duplicate class attempt s. java.lang.LinkageError-->loader (instance of org/springframework/bo ...

I Question: In our daily development, we may occasionally encounter operations that need to be in the loop (such as adding or modifying). If we directly use the for loop to traverse, it will lead to Abnormal error reporting: java.util.ConcurrentModificationException: null Case: In the official document, ConcurrentModificationExc ...

As a Java program ape, "communicating needs", "designing databases", "building tables" and "coding development" are common things. We have to do such work repeatedly almost every day, and some even enjoy it! (of course, if the money is in place ~ ~); But if you want to ask them what they are very sensitiv ...