Consider full origin path for joins in JpqlQueryBuilder.

We now consider the full join path in JpqlQueryBuilder to fix the cache key used to capture joins. Previously, we only considered the property name (a single property path segment) causing omission of joins using the same property name.

Closes #3989

Author: mp911de

spring-data-jpa/src/main/java/org/springframework/data/jpa/repository/query/JpqlQueryBuilder.java

@@ -44,6 +44,7 @@
  *
  * @author Mark Paluch
  * @author Choi Wang Gyu
+ * @since 4.0
  */
 @SuppressWarnings("JavadocDeclaration")
 public final class JpqlQueryBuilder {
@@ -804,7 +805,7 @@ public Select join(Join join) {
 				join(parent);
 			}
 
-			this.joins.put(join.joinType() + "_" + join.getName() + "_" + join.path(), join);
+			this.joins.put(join.joinType() + "_" + join.getPath(), join);
 			return this;
 		}
 
@@ -1001,6 +1002,14 @@ public interface Origin {
 		 */
 		String getName();
 
+		/**
+		 * Returns the path in dot-path notation to identify the origin uniquely. Entities typically return their entity
+		 * name while joins return a dot-path.
+		 *
+		 * @return the dot-path of this origin.
+		 */
+		String getPath();
+
 	}
 
 	/**
@@ -1028,6 +1037,11 @@ public String getName() {
 			return entity;
 		}
 
+		@Override
+		public String getPath() {
+			return getName();
+		}
+
 		public String getAlias() {
 			return alias;
 		}
@@ -1083,6 +1097,11 @@ public String getName() {
 			return path;
 		}
 
+		@Override
+		public String getPath() {
+			return source.getPath() + "." + getName();
+		}
+
 		@Override
 		public String render(RenderContext context) {
 			return "%s %s %s".formatted(joinType, context.getAlias(source), path);

spring-data-jpa/src/test/java/org/springframework/data/jpa/repository/query/JpqlQueryBuilderUnitTests.java

@@ -18,19 +18,27 @@
 import static org.assertj.core.api.Assertions.*;
 import static org.springframework.data.jpa.repository.query.JpqlQueryBuilder.*;
 
+import jakarta.persistence.Embeddable;
+import jakarta.persistence.EmbeddedId;
 import jakarta.persistence.Id;
 import jakarta.persistence.ManyToOne;
 import jakarta.persistence.OneToMany;
+import jakarta.persistence.metamodel.EntityType;
 
 import java.util.Date;
+import java.util.HashSet;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 
 import org.assertj.core.api.AbstractStringAssert;
 import org.assertj.core.api.Assertions;
 import org.junit.jupiter.api.Test;
 
+import org.springframework.data.core.PropertyPath;
+import org.springframework.data.jpa.util.TestMetaModel;
+
 /**
  * Unit tests for {@link JpqlQueryBuilder}.
  *
@@ -200,7 +208,7 @@ void joins() {
 		String fragment = JpqlQueryBuilder.where(productName).eq(literal("ex30"))
 				.and(JpqlQueryBuilder.where(personName).eq(literal("ex40"))).render(ctx(entity));
 
-		assertThat(fragment).isEqualTo("p.name = 'ex30' AND join_0.name = 'ex40'");
+		assertThat(fragment).isEqualTo("p.name = 'ex30' AND p_0.name = 'ex40'");
 	}
 
 	@Test // GH-3588
@@ -219,6 +227,27 @@ void joinOnPaths() {
 		assertThat(fragment).isEqualTo("p.name = 'ex30' AND join_0.name = 'cstrobl'");
 	}
 
+	@Test // GH-3989
+	void shouldRenderJoinsWithSamePathSegmentCorrectly() {
+
+		TestMetaModel model = TestMetaModel.hibernateModel(WithCompositeId.class, CompositeId.class, Groups.class,
+				Group.class, Person.class);
+		Entity entity = entity(WithCompositeId.class);
+
+		EntityType<WithCompositeId> entityType = model.entity(WithCompositeId.class);
+		JpqlQueryBuilder.PathExpression pas = JpqlUtils.toExpressionRecursively(model, entity, entityType,
+				PropertyPath.from("id.groups.groups.id.person.id", WithCompositeId.class));
+		String jpql = JpqlQueryBuilder.selectFrom(entity).entity().where(JpqlQueryBuilder.where(pas).isNotNull()).render();
+
+		assertThat(jpql).isEqualTo("SELECT w FROM JpqlQueryBuilderUnitTests$WithCompositeId w " //
+				+ "INNER JOIN w.id i_0 " //
+				+ "LEFT JOIN i_0.groups g " //
+				+ "LEFT JOIN g.groups g_0 " //
+				+ "INNER JOIN g_0.id i " //
+				+ "WHERE i.person.id IS NOT NULL");
+
+	}
+
 	static ContextualAssert contextual(RenderContext context) {
 		return new ContextualAssert(context);
 	}
@@ -294,4 +323,41 @@ static class Product {
 		String productType;
 
 	}
+
+	@jakarta.persistence.Entity
+	static class WithCompositeId {
+
+		@EmbeddedId CompositeId id;
+
+	}
+
+	@Embeddable
+	static class CompositeId {
+
+		@ManyToOne Groups groups;
+
+	}
+
+	@jakarta.persistence.Entity
+	static class Groups {
+
+		@Id long id;
+		@OneToMany Set<Group> groups = new HashSet<>();
+
+	}
+
+	@jakarta.persistence.Entity
+	static class Group {
+
+		@EmbeddedId GroupId id;
+
+	}
+
+	@Embeddable
+	static class GroupId {
+
+		@ManyToOne Person person;
+
+	}
+
 }