java - 重构/优化 Java 代码以获取 HostNameVerifier

Question

我有下面的java类，它检查instance是否不为空并且匹配dev/qa/stg/staging/prod 和 hostnameVerification 为 true，然后 getHostnameVerifierForInstance 返回自定义的 主机名 validator

public class SSLConfig {
    private static final String PROD_INSTANCE = "Prod";
    private static final String STG_INSTANCE1 = "Staging";
    private static final String STG_INSTANCE2 = "Stg";
    private static final String QA_INSTANCE = "QA";
    private static final String DEV_INSTANCE = "DEV";

     private static HostnameVerifier getHostnameVerifierForInstance(String instance, String hostnameVerification) {
        LOGGER.info("HostnameVerifier For Instance = {}, hostnameVerification = {}",instance,hostnameVerification);
        HostnameVerifier hostnameVerifier = new HostnameVerifier() {
            public boolean verify(String hostname, SSLSession session) {
                return true;
            }
        };
        if(StringUtils.isNotBlank(instance)) {
            if ((instance.trim().toLowerCase().startsWith(PROD_INSTANCE.toLowerCase()) || instance.trim().toLowerCase().startsWith(STG_INSTANCE1.toLowerCase()) || instance.trim().toLowerCase().startsWith(STG_INSTANCE2.toLowerCase()) || instance.trim().toLowerCase().startsWith(QA_INSTANCE.toLowerCase()) || instance.trim().toLowerCase().startsWith(DEV_INSTANCE.toLowerCase())) && StringUtils.isNotBlank(hostnameVerification) && hostnameVerification.trim().toLowerCase().equalsIgnoreCase("true")) {
                hostnameVerifier = new HostnameVerifier() {
                    public boolean verify(String hostname, SSLSession session) {
                        DefaultHostnameVerifier verifier = new DefaultHostnameVerifier();
                        return verifier.verify(hostname, session);
                    }
                };
            }
        }
        return hostnameVerifier;
    }
}

我想知道这个方法可以重构/改进为更好的版本吗？

Answer 1

重构后的代码应该是这样的:

public class SSLConfig {
    private static final String PROD_INSTANCE = "Prod";
    private static final String STG_INSTANCE1 = "Staging";
    private static final String STG_INSTANCE2 = "Stg";
    private static final String QA_INSTANCE = "QA";
    private static final String DEV_INSTANCE = "DEV";

    private static HostnameVerifier getHostnameVerifierForInstance(String instance,
                                                                   String enabled){
        return Boolean.parseBoolean(enabled)&&reject(instance) ? denyAll() 
                : permitAll();
    }

    private static boolean reject(String instance) {
        return rejections().anyMatch(instance.trim().toLowerCase()::startsWith);
    }

    private static Stream<String> rejections() {
        return Stream.of(PROD_INSTANCE, STG_INSTANCE1,
                STG_INSTANCE2, QA_INSTANCE, DEV_INSTANCE).map(String::toLowerCase);
    }

    private static HostnameVerifier denyAll() {
        return (hostname, session) -> false;
    }

    private static HostnameVerifier permitAll() {
        return (hostname, session) -> true;
    }
}