Why WHOIS Is Dead in Modern Java (And How to Check Domains with RDAP)

说明与用途

在 Java 中，用 RDAP 替代传统 WHOIS：通过 HTTPS 请求、JSON 响应、HTTP 200/404 状态码，并通过 IANA 自动发现服务器。轻量级 rdap-java 库（约 5 KB）简化代码，消除 43 端口问题。

问题

Java developers need to programmatically check domain registration status or authoritative nameservers, but legacy WHOIS requires raw TCP sockets, unstructured parsing, and is fragile.

结果

Migrating from WHOIS to RDAP in Java reduces code complexity, eliminates firewall issues, and provides reliable domain status checks with minimal dependencies (~5 KB).

工作流

• Add rdap-java dependency to Maven or Gradle
• Instantiate RDAPClient
• Call checkDomain(domain) to get RDAPResult
• Use isRegistered() to determine availability
• Access getDomain(), getServerUrl(), getNameservers() for details
• Handle RDAPException for failures
• Optionally register custom RDAP servers with registerServer()

证据

RDAP modernizes registry lookups by replacing ad-hoc text streams with established web standards

来源

To solve this, I built rdap-java—a lightweight (~5 KB) client built on top of native Java 11+ HttpClient and basic JSON parsing.

来源