hibernate-demo/src/test/java/com/ankurm/hibernatedemo/cache/MissingUpdateTimestampsRegionTest.java

package com.ankurm.hibernatedemo.cache;

import static org.assertj.core.api.Assertions.assertThat;

import org.hibernate.boot.Metadata;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.junit.jupiter.api.Test;

/**
 * Checks the original article's claim -- "Missing default-update-timestamps-region: Required for
 * the Query Cache -- omitting it causes startup errors" -- by actually omitting it, rather than
 * repeating the warning unverified. The claim is FALSE for this stack: {@code SessionFactory}
 * builds with no error at all.
 *
 * <p>{@code hibernate-jcache}'s default {@code MissingCacheStrategy} is {@code CREATE_WARN}
 * (external representation {@code "create-warn"}, confirmed by disassembling {@code
 * MissingCacheStrategy.class} in {@code hibernate-jcache-7.4.5.Final.jar}): a missing region is
 * created on the fly with provider-specific default policies, and Hibernate only logs {@code
 * HHH90001006}. Setting {@code hibernate.javax.cache.missing_cache_strategy} to {@code "fail"}
 * turns this into the hard startup error the article describes; {@code "create"} keeps the
 * auto-create behavior but silences the warning.
 *
 * <p>Docs: docs/18-ehcache-l2-configuration.md
 */
class MissingUpdateTimestampsRegionTest {

    @Test
    void queryCacheEnabled_withNoUpdateTimestampsRegionInEhcacheXml_buildsFineWithOnlyAWarning() {
        StandardServiceRegistry registry = new StandardServiceRegistryBuilder()
                .applySetting("hibernate.connection.driver_class", "org.h2.Driver")
                .applySetting("hibernate.connection.url", "jdbc:h2:mem:missingtimestamps;DB_CLOSE_DELAY=-1")
                .applySetting("hibernate.connection.username", "sa")
                .applySetting("hibernate.hbm2ddl.auto", "create")
                .applySetting("hibernate.cache.use_second_level_cache", "true")
                .applySetting("hibernate.cache.use_query_cache", "true")
                .applySetting("hibernate.cache.region.factory_class", "jcache")
                .applySetting("hibernate.javax.cache.provider", "org.ehcache.jsr107.EhcacheCachingProvider")
                .applySetting("hibernate.javax.cache.uri", "ehcache-chapter18-missing-timestamps.xml")
                .build();
        try {
            Metadata metadata = new MetadataSources(registry)
                    .addAnnotatedClass(CacheProduct.class)
                    .buildMetadata();

            Throwable thrown = catchThrowableFromBuildSessionFactory(metadata);

            System.out.println("RESULT[cache-missing-timestamps-region]: "
                    + (thrown == null
                            ? "SessionFactory built with NO error -- contrary to the original article, the "
                                    + "default MissingCacheStrategy (CREATE_WARN) auto-creates the missing "
                                    + "default-update-timestamps-region and only logs HHH90001006"
                            : thrown.getClass().getName() + ": " + rootMessage(thrown)));

            assertThat(thrown)
                    .as("corrected finding: with the default missing_cache_strategy, a missing "
                            + "default-update-timestamps-region does NOT fail SessionFactory startup")
                    .isNull();
        } finally {
            StandardServiceRegistryBuilder.destroy(registry);
        }
    }

    @Test
    void settingMissingCacheStrategyToFail_reproducesTheHardStartupErrorTheArticleDescribed() {
        StandardServiceRegistry registry = new StandardServiceRegistryBuilder()
                .applySetting("hibernate.connection.driver_class", "org.h2.Driver")
                .applySetting("hibernate.connection.url", "jdbc:h2:mem:missingtimestampsfail;DB_CLOSE_DELAY=-1")
                .applySetting("hibernate.connection.username", "sa")
                .applySetting("hibernate.hbm2ddl.auto", "create")
                .applySetting("hibernate.cache.use_second_level_cache", "true")
                .applySetting("hibernate.cache.use_query_cache", "true")
                .applySetting("hibernate.cache.region.factory_class", "jcache")
                .applySetting("hibernate.javax.cache.provider", "org.ehcache.jsr107.EhcacheCachingProvider")
                .applySetting("hibernate.javax.cache.uri", "ehcache-chapter18-missing-timestamps.xml")
                .applySetting("hibernate.javax.cache.missing_cache_strategy", "fail")
                .build();
        try {
            Metadata metadata = new MetadataSources(registry)
                    .addAnnotatedClass(CacheProduct.class)
                    .buildMetadata();

            Throwable thrown = catchThrowableFromBuildSessionFactory(metadata);

            System.out.println("RESULT[cache-missing-timestamps-region-strict]: "
                    + "hibernate.javax.cache.missing_cache_strategy=fail -> "
                    + (thrown == null ? "SessionFactory built with NO error"
                            : thrown.getClass().getName() + ": " + rootMessage(thrown))
                    + " -- this is how to opt into the hard-failure behavior the original article assumed "
                    + "was the default.");

            assertThat(thrown)
                    .as("with missing_cache_strategy explicitly set to fail, a missing "
                            + "default-update-timestamps-region does cause a startup error -- this is an "
                            + "opt-in, not the default")
                    .isNotNull();
        } finally {
            StandardServiceRegistryBuilder.destroy(registry);
        }
    }

    private static Throwable catchThrowableFromBuildSessionFactory(Metadata metadata) {
        try {
            metadata.buildSessionFactory().close();
            return null;
        } catch (Throwable t) {
            return t;
        }
    }

    private static String rootMessage(Throwable t) {
        Throwable cause = t;
        while (cause.getCause() != null) {
            cause = cause.getCause();
        }
        return cause.getMessage();
    }
}