resolves #668

hypersistence-utils-hibernate-62/src/main/java/io/hypersistence/utils/hibernate/query/SQLExtractor.java

@@ -13,6 +13,9 @@
 import org.hibernate.query.sqm.tree.select.SqmSelectStatement;
 import org.hibernate.sql.exec.spi.JdbcOperationQuerySelect;
 
+import java.lang.reflect.Field;
+import java.lang.reflect.InvocationHandler;
+import java.lang.reflect.Proxy;
 import java.util.function.Supplier;
 
 /**
@@ -36,20 +39,21 @@ protected SQLExtractor() {
      * @return the underlying SQL generated by the provided JPA query
      */
     public static String from(Query query) {
-        if(query instanceof SqmInterpretationsKey.InterpretationsKeySource &&
-           query instanceof QueryImplementor &&
-           query instanceof QuerySqmImpl) {
-            QueryInterpretationCache.Key cacheKey = SqmInterpretationsKey.createInterpretationsKey((SqmInterpretationsKey.InterpretationsKeySource) query);
-            QuerySqmImpl querySqm = (QuerySqmImpl) query;
+        Query hibernateQuery = getHibernateQuery(query);
+        if (hibernateQuery instanceof SqmInterpretationsKey.InterpretationsKeySource &&
+            hibernateQuery instanceof QueryImplementor &&
+            hibernateQuery instanceof QuerySqmImpl) {
+            QueryInterpretationCache.Key cacheKey = SqmInterpretationsKey.createInterpretationsKey((SqmInterpretationsKey.InterpretationsKeySource) hibernateQuery);
+            QuerySqmImpl querySqm = (QuerySqmImpl) hibernateQuery;
             Supplier buildSelectQueryPlan = () -> ReflectionUtils.invokeMethod(querySqm, "buildSelectQueryPlan");
-            SelectQueryPlan plan = cacheKey != null ? ((QueryImplementor) query).getSession().getFactory().getQueryEngine()
+            SelectQueryPlan plan = cacheKey != null ? ((QueryImplementor) hibernateQuery).getSession().getFactory().getQueryEngine()
                 .getInterpretationCache()
                 .resolveSelectQueryPlan(cacheKey, buildSelectQueryPlan) :
                 (SelectQueryPlan) buildSelectQueryPlan.get();
-            if(plan instanceof ConcreteSqmSelectQueryPlan) {
+            if (plan instanceof ConcreteSqmSelectQueryPlan) {
                 ConcreteSqmSelectQueryPlan selectQueryPlan = (ConcreteSqmSelectQueryPlan) plan;
                 Object cacheableSqmInterpretation = ReflectionUtils.getFieldValueOrNull(selectQueryPlan, "cacheableSqmInterpretation");
-                if(cacheableSqmInterpretation == null) {
+                if (cacheableSqmInterpretation == null) {
                     DomainQueryExecutionContext domainQueryExecutionContext = DomainQueryExecutionContext.class.cast(querySqm);
                     cacheableSqmInterpretation = ReflectionUtils.invokeStaticMethod(
                         ReflectionUtils.getMethod(
@@ -72,6 +76,30 @@ public static String from(Query query) {
                 }
             }
         }
-        return ReflectionUtils.invokeMethod(query, "getQueryString");
+        return ReflectionUtils.invokeMethod(hibernateQuery, "getQueryString");
+    }
+
+    /**
+     * Get the unproxied hibernate query underlying the provided query object.
+     *
+     * @param query JPA query
+     * @return the unproxied Hibernate query, or original query
+     */
+    private static Query getHibernateQuery(Query query) {
+        try {
+            if (query instanceof QuerySqmImpl || !Proxy.isProxyClass(query.getClass())) {
+                return query;
+            }
+            // is proxyied, get it out
+            InvocationHandler invocationHandler = Proxy.getInvocationHandler(query);
+            Class<?> innerClass = invocationHandler.getClass();
+            Field targetField = innerClass.getDeclaredField("target");
+            targetField.setAccessible(true);
+            return (Query) targetField.get(invocationHandler);
+        } catch (NoSuchFieldException exception) {
+            return query; // seems it cannot extract it, probably not a hibernate proxy
+        } catch (IllegalAccessException exception) {
+            throw new RuntimeException(exception);
+        }
     }
 }

hypersistence-utils-hibernate-62/src/test/java/io/hypersistence/utils/hibernate/query/SQLExtractorTest.java

@@ -1,13 +1,24 @@
 package io.hypersistence.utils.hibernate.query;
 
 import io.hypersistence.utils.hibernate.util.AbstractPostgreSQLIntegrationTest;
-import jakarta.persistence.*;
+import jakarta.persistence.Column;
+import jakarta.persistence.Entity;
+import jakarta.persistence.EntityManager;
+import jakarta.persistence.FetchType;
+import jakarta.persistence.Id;
+import jakarta.persistence.ManyToOne;
+import jakarta.persistence.Query;
+import jakarta.persistence.Table;
+import jakarta.persistence.Tuple;
 import jakarta.persistence.criteria.CriteriaBuilder;
 import jakarta.persistence.criteria.CriteriaQuery;
 import jakarta.persistence.criteria.Join;
 import jakarta.persistence.criteria.Root;
 import org.junit.Test;
 
+import java.lang.reflect.InvocationHandler;
+import java.lang.reflect.Method;
+import java.lang.reflect.Proxy;
 import java.time.LocalDate;
 
 import static org.junit.Assert.assertNotNull;
@@ -53,24 +64,27 @@ public void testJPQL() {
     @Test
     public void testCriteriaAPI() {
         doInJPA(entityManager -> {
-            CriteriaBuilder builder = entityManager.getCriteriaBuilder();
+            Query criteriaQuery = createTestQuery(entityManager);
 
-            CriteriaQuery<PostComment> criteria = builder.createQuery(PostComment.class);
-
-            Root<PostComment> postComment = criteria.from(PostComment.class);
-            Join<PostComment, Post> post = postComment.join("post");
+            String sql = SQLExtractor.from(criteriaQuery);
 
-            criteria.where(
-                builder.like(post.get("title"), "%Java%")
-            );
+            assertNotNull(sql);
 
-            criteria.orderBy(
-                builder.asc(postComment.get("id"))
+            LOGGER.info(
+                "The Criteria API query: [\n{}\n]\ngenerates the following SQL query: [\n{}\n]",
+                criteriaQuery.unwrap(org.hibernate.query.Query.class).getQueryString(),
+                sql
             );
+        });
+    }
 
-            Query criteriaQuery = entityManager.createQuery(criteria);
+    @Test
+    public void testCriteriaAPIWithProxy() {
+        doInJPA(entityManager -> {
+            Query criteriaQuery = createTestQuery(entityManager);
+            Query proxiedQuery = proxy(criteriaQuery);
 
-            String sql = SQLExtractor.from(criteriaQuery);
+            String sql = SQLExtractor.from(proxiedQuery);
 
             assertNotNull(sql);
 
@@ -82,6 +96,29 @@ public void testCriteriaAPI() {
         });
     }
 
+    private static Query proxy(Query criteriaQuery) {
+        return (Query) Proxy.newProxyInstance(Query.class.getClassLoader(), new Class[]{Query.class}, new HibernateLikeInvocationHandler(criteriaQuery));
+    }
+
+    private static Query createTestQuery(EntityManager entityManager) {
+        CriteriaBuilder builder = entityManager.getCriteriaBuilder();
+
+        CriteriaQuery<PostComment> criteria = builder.createQuery(PostComment.class);
+
+        Root<PostComment> postComment = criteria.from(PostComment.class);
+        Join<PostComment, Post> post = postComment.join("post");
+
+        criteria.where(
+            builder.like(post.get("title"), "%Java%")
+        );
+
+        criteria.orderBy(
+            builder.asc(postComment.get("id"))
+        );
+
+        return entityManager.createQuery(criteria);
+    }
+
     @Entity(name = "Post")
     @Table(name = "post")
     public static class Post {
@@ -161,4 +198,17 @@ public PostComment setReview(String review) {
             return this;
         }
     }
+
+    private static class HibernateLikeInvocationHandler implements InvocationHandler {
+        private final Query target; // has to be named "target" because this is how Hibernate implements it, and the extracting code has to be quite invasive to get the query from the Hibernate proxy
+
+        public HibernateLikeInvocationHandler(Query query) {
+            this.target = query;
+        }
+
+        @Override
+        public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
+            return method.invoke(target, args);
+        }
+    }
 }