Java implementation of picture verification code specific code

This example shares the java image verification code for your reference. The specific contents are as follows

Web page display effect:

index. JSP uses two methods to force picture update: 1. Do not cache when setting picture output. 2. Change the requested address with JS.

Java code for automatically generating verification code

Key classes (the following classes are the contents of the basic part) bufferedimageio graphics / graphics2d

web. xml