Implementation method of Java verification code function

1、 Foreword

It can be said that the verification code has been very common in our life. Any website and any app will have this function, but why do we have this? How can we do it? The following small series will lead you to complete the function of a verification code in Java.

2、 Function of verification code

Generally, it can prevent someone from using the robot to automatically register in batches and continuously log in and fill water for specific registered users by means of violent cracking of specific programs. Because the verification code is a picture mixed with numbers and symbols, it seems difficult for human eyes, and it is even more difficult for machines to recognize it.

3、 Java implementation

3.1 servlet class for establishing verification code:

3.2 web under WEB-INF file XML configuration Servlet

3.3 foreground call Servlet

Jsp code:

js：

4、 Summary

Through this study of verification code, I also have a certain understanding of the interaction and data transmission between the whole servlet and foreground code. Therefore, I still need to learn more about these skills and summarize more in the future. In this way, knowledge will be solid.

The above is the whole content of this article. I hope it will be helpful to your study, and I hope you can support programming tips.