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PDF fraud is a backend problem, and in enterprise fintech, lending, banking, and insurance the backend runs on the JVM. A Spring Boot service ingests an uploaded bank statement, a payslip, or a claim packet, writes a row, and hands the document to underwriting — and by the time your @RestController has returned 201, the document’s claims have already propagated into your business logic. Your KYC provider verified that the applicant is a real person with a valid identity. It said nothing about whether the PDF they uploaded was edited after the bank generated it. That structural-tampering layer is invisible to identity verification, and the right place to catch it is at ingress: before your service trusts the file, not after.
This guide walks through integrating the PDF tamper detection API into a Spring Boot application — from the first curl command to an idiomatic @Service built on Spring’s RestClient, with a typed record DTO, @ConfigurationProperties for the API key, error handling that distinguishes a configuration failure from a transient one, and a small bank-statement gate that decides accept / reject / review. The patterns target Spring Boot 3.2+ / Spring Framework 6.1+ (where RestClient is stable); a WebClient variant is included for reactive stacks. Treat the code as a reference architecture — it runs the real request flow against the documented error codes, but you should adapt and harden it for your own traffic profile and threat model. (If you want the conceptual overview first, start with How to Detect PDF Tampering Programmatically. Integrating from another stack? See the Go, Node.js, Python, and Laravel / PHP guides.)
