How to sanitize and validate user input to pass a Checkmarx scan

in .Net framework > 4.0 use AntiXSS

AntiXssEncoder.HtmlEncode()

HtmlUtils from spring-web got the job done with:

HtmlUtils.htmlEscape(x)

Maven dependency:

<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-web</artifactId>
    <version>5.1.7.RELEASE</version>
</dependency>