Add migration-5-to-7 module: Hibernate 5.6.15 vs 7.4.14 jar diff, compile checks, schema defaults and cheat-sheet snippets

Co-Authored-By: Claude Sonnet 5.5 <[email protected]> Claude-Session: https://claude.ai/code/session_01YPgGH6aMbSLANL3E2HHmS6
2026-10-25 19:17:24 +00:00
parent 357ba84e5c
commit aea104f021
57 changed files with 5187 additions and 0 deletions
@@ -0,0 +1,64 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <groupId>com.ankurm</groupId>
+  <artifactId>migration-h5</artifactId>
+  <version>1.0.0</version>
+  <name>migration-h5</name>
+  <description>The "before" side: Hibernate ORM 5.6.15.Final with javax.persistence, run against in-memory H2</description>
+
+  <properties>
+    <maven.compiler.release>17</maven.compiler.release>
+    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+    <hibernate.version>5.6.15.Final</hibernate.version>
+  </properties>
+
+  <dependencyManagement>
+    <dependencies>
+      <!-- Hibernate 5.6.15 pulls Byte Buddy 1.12.18, which does not know the JDK this runs on; a current one does -->
+      <dependency>
+        <groupId>net.bytebuddy</groupId>
+        <artifactId>byte-buddy</artifactId>
+        <version>1.17.7</version>
+      </dependency>
+    </dependencies>
+  </dependencyManagement>
+
+  <dependencies>
+    <dependency>
+      <!-- note the group id: org.hibernate here, org.hibernate.orm from 6.0 on -->
+      <groupId>org.hibernate</groupId>
+      <artifactId>hibernate-core</artifactId>
+      <version>${hibernate.version}</version>
+    </dependency>
+    <dependency>
+      <groupId>com.h2database</groupId>
+      <artifactId>h2</artifactId>
+      <version>2.4.240</version>
+    </dependency>
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter</artifactId>
+      <version>6.1.3</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.assertj</groupId>
+      <artifactId>assertj-core</artifactId>
+      <version>3.27.7</version>
+      <scope>test</scope>
+    </dependency>
+  </dependencies>
+
+  <build>
+    <plugins>
+      <plugin>
+        <artifactId>maven-surefire-plugin</artifactId>
+        <version>3.6.0</version>
+      </plugin>
+    </plugins>
+  </build>
+</project>
@@ -0,0 +1,68 @@
+package com.ankurm.migration;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.io.Serializable;
+import java.util.List;
+
+import org.hibernate.Session;
+import org.hibernate.criterion.Restrictions;
+import org.junit.jupiter.api.Test;
+
+/** The same probes as the Hibernate 7 module, run on 5.6.15.Final. Output goes to ../output. */
+class BaselineTest {
+
+    private static final String V = "5.6.15";
+
+    @Test
+    void schemaDefaults() {
+        try (Db db = new Db(Probe.class); Transcript t = new Transcript("06-schema-" + V)) {
+            t.line("Hibernate " + V + ", H2, @GeneratedValue with no strategy");
+            t.line("-- sequences (name, increment)");
+            List<String> seq = db.jdbc("select sequence_name, increment from information_schema.sequences order by 1");
+            seq.forEach(t::line);
+            t.line("-- columns of PROBE (name, type)");
+            List<String> cols = db.jdbc("select column_name, data_type from information_schema.columns where table_name = 'PROBE' order by column_name");
+            cols.forEach(t::line);
+            assertThat(seq).isNotEmpty();
+            assertThat(cols).hasSize(11);
+        }
+    }
+
+    @Test
+    void legacyQueries() {
+        try (Db db = new Db(Probe.class); Transcript t = new Transcript("07-legacy-queries-" + V)) {
+            t.line("Hibernate " + V);
+            try (Session s = db.sessionFactory.openSession()) {
+                s.beginTransaction();
+                Serializable id = s.save(new Probe("alpha"));
+                t.line("session.save(...) returned: " + id + " (" + id.getClass().getSimpleName() + ")");
+                s.getTransaction().commit();
+                assertThat(id).isNotNull();
+            }
+            try (Session s = db.sessionFactory.openSession()) {
+                String ordinal = outcome(() -> s.createQuery("from Probe p where p.name = ?1").setParameter(1, "alpha").list());
+                t.line("HQL with ?1                      : " + ordinal);
+                String bare = outcome(() -> s.createQuery("from Probe p where p.name = ?").setParameter(0, "alpha").list());
+                t.line("HQL with a bare ?                : " + bare);
+                String enumInt = outcome(() -> s.createQuery("from Probe p where p.byOrdinal = 0").list());
+                t.line("HQL enum compared with 0         : " + enumInt);
+                String criteria = outcome(() -> s.createCriteria(Probe.class).add(Restrictions.eq("name", "alpha")).list());
+                t.line("session.createCriteria(...)      : " + criteria);
+                assertThat(ordinal).startsWith("1 row");
+                assertThat(bare).startsWith("failed");
+                assertThat(enumInt).startsWith("0 row");
+                assertThat(criteria).startsWith("1 row");
+            }
+        }
+    }
+
+    static String outcome(java.util.function.Supplier<List<?>> query) {
+        try {
+            return query.get().size() + " row(s)";
+        } catch (RuntimeException e) {
+            String msg = String.valueOf(e.getMessage()).lines().findFirst().orElse("");
+            return "failed: " + e.getClass().getSimpleName() + ": " + (msg.length() > 140 ? msg.substring(0, 140) + "..." : msg);
+        }
+    }
+}
@@ -0,0 +1,66 @@
+package com.ankurm.migration;
+
+import org.hibernate.SessionFactory;
+import org.hibernate.boot.MetadataSources;
+import org.hibernate.boot.registry.StandardServiceRegistry;
+import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Statement;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.atomic.AtomicInteger;
+
+/** Plain-Hibernate bootstrap against in-memory H2. */
+final class Db implements AutoCloseable {
+
+    private static final AtomicInteger SEQ = new AtomicInteger();
+    final SessionFactory sessionFactory;
+    private final String url;
+
+    Db(Class<?>... entities) {
+        this.url = "jdbc:h2:mem:mig" + SEQ.incrementAndGet() + ";DB_CLOSE_DELAY=-1";
+        StandardServiceRegistry registry = new StandardServiceRegistryBuilder()
+                .applySetting("hibernate.connection.url", url)
+                .applySetting("hibernate.connection.username", "sa")
+                .applySetting("hibernate.connection.password", "")
+                .applySetting("hibernate.hbm2ddl.auto", "create-drop")
+                .build();
+        MetadataSources sources = new MetadataSources(registry);
+        for (Class<?> e : entities) {
+            sources.addAnnotatedClass(e);
+        }
+        this.sessionFactory = sources.buildMetadata().buildSessionFactory();
+    }
+
+    /** Raw JDBC against the same in-memory database; columns joined with a space. */
+    List<String> jdbc(String query) {
+        List<String> rows = new ArrayList<>();
+        try (Connection c = DriverManager.getConnection(url, "sa", "");
+             Statement st = c.createStatement();
+             ResultSet rs = st.executeQuery(query)) {
+            int n = rs.getMetaData().getColumnCount();
+            while (rs.next()) {
+                StringBuilder sb = new StringBuilder();
+                for (int i = 1; i <= n; i++) {
+                    if (i > 1) {
+                        sb.append(' ');
+                    }
+                    sb.append(rs.getString(i));
+                }
+                rows.add(sb.toString());
+            }
+        } catch (SQLException e) {
+            throw new IllegalStateException(e);
+        }
+        return rows;
+    }
+
+    @Override
+    public void close() {
+        sessionFactory.close();
+    }
+}
@@ -0,0 +1,39 @@
+package com.ankurm.migration;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.nio.file.Files;
+import java.nio.file.Path;
+
+import org.hibernate.Session;
+import org.hibernate.SessionFactory;
+import org.hibernate.boot.MetadataSources;
+import org.hibernate.boot.registry.StandardServiceRegistry;
+import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
+import org.junit.jupiter.api.Test;
+
+/** Creates the schema Hibernate 5.6.15 generates, in an H2 file database that the Hibernate 7 module opens later. */
+class LegacySchemaTest {
+
+    @Test
+    void createSchemaFile() throws Exception {
+        Path dir = Path.of("..", "target", "legacy-db");
+        Files.createDirectories(dir);
+        for (var f : dir.toFile().listFiles()) {
+            f.delete();
+        }
+        StandardServiceRegistry registry = new StandardServiceRegistryBuilder()
+                .applySetting("hibernate.connection.url", "jdbc:h2:file:" + dir.toAbsolutePath().normalize() + "/probe")
+                .applySetting("hibernate.connection.username", "sa")
+                .applySetting("hibernate.connection.password", "")
+                .applySetting("hibernate.hbm2ddl.auto", "create")
+                .build();
+        try (SessionFactory sf = new MetadataSources(registry).addAnnotatedClass(Probe.class).buildMetadata().buildSessionFactory();
+             Session s = sf.openSession()) {
+            s.beginTransaction();
+            s.persist(new Probe("legacy row"));
+            s.getTransaction().commit();
+        }
+        assertThat(Files.exists(dir.resolve("probe.mv.db"))).isTrue();
+    }
+}
@@ -0,0 +1,46 @@
+package com.ankurm.migration;
+
+import javax.persistence.Entity;
+import javax.persistence.EnumType;
+import javax.persistence.Enumerated;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+
+import java.math.BigDecimal;
+import java.time.Duration;
+import java.time.Instant;
+import java.time.LocalDateTime;
+import java.util.UUID;
+
+/** One field of each type whose default column mapping is worth comparing, and a generated id. */
+@Entity
+public class Probe {
+
+    @Id
+    @GeneratedValue
+    Long id;
+
+    String name;
+    boolean active;
+    Instant createdAt;
+    LocalDateTime occurredAt;
+    UUID uuid;
+    Duration span;
+    BigDecimal price;
+    byte[] payload;
+
+    @Enumerated(EnumType.ORDINAL)
+    Colour byOrdinal;
+
+    @Enumerated(EnumType.STRING)
+    Colour byName;
+
+    public enum Colour { RED, GREEN }
+
+    public Probe() {
+    }
+
+    Probe(String name) {
+        this.name = name;
+    }
+}
@@ -0,0 +1,33 @@
+package com.ankurm.migration;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.List;
+
+/** Collects lines and writes them to output/NN-name.txt when closed. The tests assert what they print. */
+final class Transcript implements AutoCloseable {
+
+    private final Path file;
+    private final List<String> lines = new ArrayList<>();
+
+    Transcript(String name) {
+        this.file = Path.of("..", "output", name + ".txt");
+    }
+
+    Transcript line(String s) {
+        lines.add(s);
+        return this;
+    }
+
+    @Override
+    public void close() {
+        try {
+            Files.createDirectories(file.getParent());
+            Files.write(file, lines);
+        } catch (IOException e) {
+            throw new IllegalStateException(e);
+        }
+    }
+}