Java和PHP语言中的Hash256返回的结果不同

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class HashExample {
    public static void main(String[] args) {
        try {
            String input = "Hello World";
            MessageDigest md = MessageDigest.getInstance("SHA-256");
            byte[] hashBytes = md.digest(input.getBytes());
            StringBuilder hexString = new StringBuilder();

            for (byte b : hashBytes) {
                String hex = Integer.toHexString(0xff & b);
                if (hex.length() == 1) hexString.append('0');
                hexString.append(hex);
            }

            System.out.println("Java Hash256 Result: " + hexString.toString());
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        }
    }
}

<?php
$input = "Hello World";
$hash = hash("sha256", $input);
echo "PHP Hash256 Result: " . $hash;
?>