Add support for JPA mapping resources

Closes gh-10684

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/orm/jpa/JpaBaseConfiguration.java

@@ -130,7 +130,8 @@ public abstract class JpaBaseConfiguration implements BeanFactoryAware {
 		Map<String, Object> vendorProperties = getVendorProperties();
 		customizeVendorProperties(vendorProperties);
 		return factoryBuilder.dataSource(this.dataSource).packages(getPackagesToScan())
-				.properties(vendorProperties).jta(isJta()).build();
+				.properties(vendorProperties).mappingResources(getMappingResources())
+				.jta(isJta()).build();
 	}
 
 	protected abstract AbstractJpaVendorAdapter createJpaVendorAdapter();
@@ -158,6 +159,11 @@ public abstract class JpaBaseConfiguration implements BeanFactoryAware {
 		return packages.toArray(new String[packages.size()]);
 	}
 
+	private String[] getMappingResources() {
+		List<String> mappingResources = this.properties.getMappingResources();
+		return mappingResources.toArray(new String[mappingResources.size()]);
+	}
+
 	/**
 	 * Return the JTA transaction manager.
 	 * @return the transaction manager or {@code null}

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/orm/jpa/JpaProperties.java

@@ -16,7 +16,9 @@
 
 package org.springframework.boot.autoconfigure.orm.jpa;
 
+import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Map;
 
 import javax.sql.DataSource;
@@ -43,6 +45,11 @@ public class JpaProperties {
 	 */
 	private Map<String, String> properties = new HashMap<>();
 
+	/**
+	 * Mapping resources (equivalent to "mapping-file" entries in persistence.xml).
+	 */
+	private final List<String> mappingResources = new ArrayList<>();
+
 	/**
 	 * Name of the target database to operate on, auto-detected by default. Can be
 	 * alternatively set using the "Database" enum.
@@ -75,6 +82,10 @@ public class JpaProperties {
 		this.properties = properties;
 	}
 
+	public List<String> getMappingResources() {
+		return this.mappingResources;
+	}
+
 	public String getDatabasePlatform() {
 		return this.databasePlatform;
 	}

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/orm/jpa/HibernateJpaAutoConfigurationTests.java

@@ -45,6 +45,7 @@ import org.springframework.boot.autoconfigure.flyway.FlywayAutoConfiguration;
 import org.springframework.boot.autoconfigure.jdbc.DataSourceTransactionManagerAutoConfiguration;
 import org.springframework.boot.autoconfigure.jdbc.XADataSourceAutoConfiguration;
 import org.springframework.boot.autoconfigure.liquibase.LiquibaseAutoConfiguration;
+import org.springframework.boot.autoconfigure.orm.jpa.mapping.NonAnnotatedEntity;
 import org.springframework.boot.autoconfigure.orm.jpa.test.City;
 import org.springframework.boot.autoconfigure.transaction.jta.JtaAutoConfiguration;
 import org.springframework.boot.orm.jpa.hibernate.SpringJtaPlatform;
@@ -255,6 +256,22 @@ public class HibernateJpaAutoConfigurationTests
 				});
 	}
 
+	@Test
+	public void customResourceMapping() {
+		contextRunner()
+				.withClassLoader(new HideDataScriptClassLoader())
+				.withPropertyValues(
+						"spring.datasource.data:classpath:/db/non-annotated-data.sql",
+						"spring.jpa.mapping-resources=META-INF/mappings/non-annotated.xml")
+				.run((context) -> {
+					EntityManager em = context.getBean(EntityManagerFactory.class)
+							.createEntityManager();
+					NonAnnotatedEntity found = em.find(NonAnnotatedEntity.class, 2000L);
+					assertThat(found).isNotNull();
+					assertThat(found.getValue()).isEqualTo("Test");
+				});
+	}
+
 	@Configuration
 	@TestAutoConfigurationPackage(City.class)
 	static class TestInitializedJpaConfiguration {

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/orm/jpa/mapping/NonAnnotatedEntity.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright 2012-2017 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.autoconfigure.orm.jpa.mapping;
+
+/**
+ * A non annotated entity that is handled by a custom "mapping-file".
+ *
+ * @author Stephane Nicoll
+ */
+public class NonAnnotatedEntity {
+
+	private Long id;
+
+	private String value;
+
+	protected NonAnnotatedEntity() {
+	}
+
+	public NonAnnotatedEntity(String value) {
+		this.value = value;
+	}
+
+	public Long getId() {
+		return this.id;
+	}
+
+	public void setId(Long id) {
+		this.id = id;
+	}
+
+	public String getValue() {
+		return this.value;
+	}
+
+	public void setValue(String value) {
+		this.value = value;
+	}
+
+}

spring-boot-project/spring-boot-autoconfigure/src/test/resources/META-INF/mappings/non-annotated.xml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<entity-mappings xmlns="http://xmlns.jcp.org/xml/ns/persistence/orm"
+				 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+				 xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence/orm http://xmlns.jcp.org/xml/ns/persistence/orm_2_1.xsd"
+				 version="2.1">
+	<entity class="org.springframework.boot.autoconfigure.orm.jpa.mapping.NonAnnotatedEntity">
+		<table name="NON_ANNOTATED"/>
+		<attributes>
+			<id name="id">
+				<column name="id"/>
+				<generated-value strategy="IDENTITY"/>
+			</id>
+			<basic name="value">
+				<column name="value"/>
+			</basic>
+		</attributes>
+	</entity>
+</entity-mappings>

spring-boot-project/spring-boot-autoconfigure/src/test/resources/db/non-annotated-data.sql

@@ -0,0 +1 @@
+INSERT INTO NON_ANNOTATED (ID, VALUE) values (2000, 'Test');

spring-boot-project/spring-boot-docs/src/main/asciidoc/appendix-application-properties.adoc

@@ -714,6 +714,7 @@ content into your application; rather pick only the properties that you need.
 	spring.jpa.hibernate.naming.implicit-strategy= # Hibernate 5 implicit naming strategy fully qualified name.
 	spring.jpa.hibernate.naming.physical-strategy= # Hibernate 5 physical naming strategy fully qualified name.
 	spring.jpa.hibernate.use-new-id-generator-mappings= # Use Hibernate's newer IdentifierGenerator for AUTO, TABLE and SEQUENCE.
+	spring.jpa.mapping-resources= # Mapping resources (equivalent to "mapping-file" entries in persistence.xml).
 	spring.jpa.open-in-view=true # Register OpenEntityManagerInViewInterceptor. Binds a JPA EntityManager to the thread for the entire processing of the request.
 	spring.jpa.properties.*= # Additional native properties to set on the JPA provider.
 	spring.jpa.show-sql=false # Enable logging of SQL statements.

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/orm/jpa/EntityManagerFactoryBuilder.java

@@ -113,6 +113,8 @@ public class EntityManagerFactoryBuilder {
 
 		private Map<String, Object> properties = new HashMap<>();
 
+		private String[] mappingResources;
+
 		private boolean jta;
 
 		private Builder(DataSource dataSource) {
@@ -166,6 +168,20 @@ public class EntityManagerFactoryBuilder {
 			return this;
 		}
 
+		/**
+		 * The mapping resources (equivalent to {@code <mapping-file>} entries in
+		 * {@code persistence.xml}) for the persistence unit.
+		 * <p>Note that mapping resources must be relative to the classpath root,
+		 * e.g. "META-INF/mappings.xml" or "com/mycompany/repository/mappings.xml",
+		 * so that they can be loaded through {@code ClassLoader.getResource}.
+		 * @param mappingResources the mapping resources to use
+		 * @return the builder for fluent usage
+		 */
+		public Builder mappingResources(String... mappingResources) {
+			this.mappingResources = mappingResources;
+			return this;
+		}
+
 		/**
 		 * Configure if using a JTA {@link DataSource}, i.e. if
 		 * {@link LocalContainerEntityManagerFactoryBean#setDataSource(DataSource)
@@ -203,6 +219,9 @@ public class EntityManagerFactoryBuilder {
 			entityManagerFactoryBean.getJpaPropertyMap()
 					.putAll(EntityManagerFactoryBuilder.this.jpaProperties);
 			entityManagerFactoryBean.getJpaPropertyMap().putAll(this.properties);
+			if (this.mappingResources != null) {
+				entityManagerFactoryBean.setMappingResources(this.mappingResources);
+			}
 			URL rootLocation = EntityManagerFactoryBuilder.this.persistenceUnitRootLocation;
 			if (rootLocation != null) {
 				entityManagerFactoryBean