Tamper-evident verification
Verify donation ledger integrity
This page recalculates every block hash and checks whether each previousHash matches the block before it. If someone changes a record, the chain breaks.
Ledger status
Run verification to calculate the current ledger proof.
Verify one hash
Paste a hash copied from the records table to find its exact donation record.
Matched record
Search for a copied hash to display the verified record details here.
How your Java version can explain blockchain
1. Store a block
A DonationRecord object stores donor code, blood group, hospital, date, and previousHash.
2. Generate SHA-256
Java MessageDigest converts record data into a fixed hash string.
3. Verify chain
Recalculate hashes and compare previousHash values to detect tampering.