fix conflicts

2019-05-10 23:22:52 +03:00
parent ba8fce515b 01492d1674
commit 6f7ebf8574
1803 changed files with 33727 additions and 6129 deletions
@@ -76,4 +76,5 @@ persistence-modules/hibernate5/transaction.log
 apache-avro/src/main/java/com/baeldung/avro/model/
 jta/transaction-logs/
 software-security/sql-injection-samples/derby.log
-spring-soap/src/main/java/com/baeldung/springsoap/gen/
+spring-soap/src/main/java/com/baeldung/springsoap/gen/
+/report-*.json
@@ -60,7 +60,6 @@
    <properties>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
-		<junit.version>4.10</junit.version>
 		<meecrowave-junit.version>1.2.0</meecrowave-junit.version>
 		<okhttp.version>3.10.0</okhttp.version>
 		<meecrowave-jpa.version>1.2.1</meecrowave-jpa.version>
@@ -0,0 +1,21 @@
+##  OData test URLs
+
+This following table contains test URLs that can be used with the Olingo V2 demo project.
+
+| URL                                      | Description                                     |
+|------------------------------------------|-------------------------------------------------|
+| `http://localhost:8180/odata/$metadata`  | fetch OData metadata document |
+| `http://localhost:8180/odata/CarMakers?$top=10&$skip=10` | Get 10 entities starting at offset 10 |
+| `http://localhost:8180/odata/CarMakers?$count` | Return total count of entities in this set |
+| `http://localhost:8180/odata/CarMakers?$filter=startswith(Name,'B')` | Return entities where the *Name* property starts with 'B' |
+| `http://localhost:8180/odata/CarModels?$filter=Year eq 2008 and CarMakerDetails/Name eq 'BWM'` | Return *CarModel* entities where the *Name* property of its maker  starts with 'B' |
+| `http://localhost:8180/odata/CarModels(1L)?$expand=CarMakerDetails` | Return the *CarModel* with primary key '1', along with its maker|
+| `http://localhost:8180/odata/CarModels(1L)?$select=Name,Sku` | Return the *CarModel* with primary key '1', returing only its *Name* and *Sku* properties |
+| `http://localhost:8180/odata/CarModels?$orderBy=Name asc,Sku desc` | Return *CarModel* entities, ordered by the their *Name* and *Sku* properties |
+| `http://localhost:8180/odata/CarModels?$format=json` | Return *CarModel* entities, using a JSON representation|
+
+
+
+
+
+
@@ -0,0 +1,29 @@
+HELP.md
+/target/
+!.mvn/wrapper/maven-wrapper.jar
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+/build/
+
+### VS Code ###
+.vscode/
@@ -0,0 +1,108 @@
+<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>2.1.3.RELEASE</version>
+		<relativePath /> <!-- lookup parent from repository -->
+	</parent>
+	<groupId>org.baeldung.examples.olingo2</groupId>
+	<artifactId>olingo2-sample</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<name>olingo2-sample</name>
+	<description>Sample Olingo 2 Project</description>
+
+	<properties>
+		<java.version>1.8</java.version>
+		<olingo2.version>2.0.11</olingo2.version>
+	</properties>
+
+	<dependencies>
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-jersey</artifactId>
+		</dependency>
+
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-data-jpa</artifactId>
+		</dependency>
+
+
+		<dependency>
+			<groupId>com.h2database</groupId>
+			<artifactId>h2</artifactId>
+			<scope>runtime</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-configuration-processor</artifactId>
+			<optional>true</optional>
+		</dependency>
+		<dependency>
+			<groupId>org.projectlombok</groupId>
+			<artifactId>lombok</artifactId>
+			<optional>true</optional>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+
+		<!-- Olingo 2 Dependencies -->
+		<dependency>
+			<groupId>org.apache.olingo</groupId>
+			<artifactId>olingo-odata2-core</artifactId>
+			<version>${olingo2.version}</version>
+			<!-- Avoid jax-rs version conflict by excluding Olingo's version -->
+			<exclusions>
+				<exclusion>
+					<groupId>javax.ws.rs</groupId>
+					<artifactId>javax.ws.rs-api</artifactId>
+				</exclusion>
+			</exclusions>
+		</dependency>
+		<dependency>
+			<groupId>org.apache.olingo</groupId>
+			<artifactId>olingo-odata2-api</artifactId>
+			<version>${olingo2.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>org.apache.olingo</groupId>
+			<artifactId>olingo-odata2-jpa-processor-api</artifactId>
+			<version>${olingo2.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>org.apache.olingo</groupId>
+			<artifactId>olingo-odata2-jpa-processor-core</artifactId>
+			<version>${olingo2.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>org.apache.olingo</groupId>
+			<artifactId>olingo-odata2-jpa-processor-ref</artifactId>
+			<version>${olingo2.version}</version>
+			<exclusions>
+				<exclusion>
+					<groupId>org.eclipse.persistence</groupId>
+					<artifactId>eclipselink</artifactId>
+				</exclusion>
+			</exclusions>
+		</dependency>
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+			</plugin>
+		</plugins>
+	</build>
+
+</project>
@@ -0,0 +1,298 @@
+package org.baeldung.examples.olingo2;
+
+import java.util.List;
+import java.util.Map;
+
+import javax.persistence.EntityGraph;
+import javax.persistence.EntityManager;
+import javax.persistence.EntityManagerFactory;
+import javax.persistence.EntityTransaction;
+import javax.persistence.FlushModeType;
+import javax.persistence.LockModeType;
+import javax.persistence.Persistence;
+import javax.persistence.Query;
+import javax.persistence.StoredProcedureQuery;
+import javax.persistence.SynchronizationType;
+import javax.persistence.TypedQuery;
+import javax.persistence.criteria.CriteriaBuilder;
+import javax.persistence.criteria.CriteriaDelete;
+import javax.persistence.criteria.CriteriaQuery;
+import javax.persistence.criteria.CriteriaUpdate;
+import javax.persistence.metamodel.Metamodel;
+import javax.servlet.http.HttpServletRequest;
+
+import org.apache.olingo.odata2.api.processor.ODataContext;
+import org.apache.olingo.odata2.jpa.processor.api.ODataJPAContext;
+import org.apache.olingo.odata2.jpa.processor.api.ODataJPAServiceFactory;
+import org.apache.olingo.odata2.jpa.processor.api.exception.ODataJPARuntimeException;
+import org.baeldung.examples.olingo2.JerseyConfig.EntityManagerFilter;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.orm.jpa.EntityManagerFactoryUtils;
+import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
+import org.springframework.stereotype.Component;
+
+/**
+ * ODataJPAServiceFactory implementation for our sample domain 
+ * @author Philippe
+ *
+ */
+@Component
+public class CarsODataJPAServiceFactory extends ODataJPAServiceFactory {
+
+    private static final Logger log = LoggerFactory.getLogger(CarsODataJPAServiceFactory.class);
+
+    public CarsODataJPAServiceFactory() {
+        // Enable detailed error messages (useful for debugging)
+        setDetailErrors(true);
+    }
+
+    /**
+     * This method will be called by Olingo on every request to
+     * initialize the ODataJPAContext that will be used. 
+     */
+    @Override
+    public ODataJPAContext initializeODataJPAContext() throws ODataJPARuntimeException {
+
+        log.info("[I32] >>> initializeODataJPAContext()");
+        ODataJPAContext ctx = getODataJPAContext();
+        ODataContext octx = ctx.getODataContext();
+        HttpServletRequest request = (HttpServletRequest)octx.getParameter(ODataContext.HTTP_SERVLET_REQUEST_OBJECT);
+        EntityManager em = (EntityManager)request.getAttribute(EntityManagerFilter.EM_REQUEST_ATTRIBUTE);
+                
+        // Here we're passing the EM that was created by the EntityManagerFilter (see JerseyConfig)
+        ctx.setEntityManager(new EntityManagerWrapper(em));
+        ctx.setPersistenceUnitName("default");
+        
+        // We're managing the EM's lifecycle, so we must inform Olingo that it should not
+        // try to manage transactions and/or persistence sessions
+        ctx.setContainerManaged(true);                
+        return ctx;
+    }
+
+    static class EntityManagerWrapper implements EntityManager {
+
+        private EntityManager delegate;
+
+        public void persist(Object entity) {
+            log.info("[I68] persist: entity.class=" + entity.getClass()
+                .getSimpleName());
+            delegate.persist(entity);
+            // delegate.flush();
+        }
+
+        public <T> T merge(T entity) {
+            log.info("[I74] merge: entity.class=" + entity.getClass()
+                .getSimpleName());
+            return delegate.merge(entity);
+        }
+
+        public void remove(Object entity) {
+            log.info("[I78] remove: entity.class=" + entity.getClass()
+                .getSimpleName());
+            delegate.remove(entity);
+        }
+
+        public <T> T find(Class<T> entityClass, Object primaryKey) {
+            return delegate.find(entityClass, primaryKey);
+        }
+
+        public <T> T find(Class<T> entityClass, Object primaryKey, Map<String, Object> properties) {
+            return delegate.find(entityClass, primaryKey, properties);
+        }
+
+        public <T> T find(Class<T> entityClass, Object primaryKey, LockModeType lockMode) {
+            return delegate.find(entityClass, primaryKey, lockMode);
+        }
+
+        public <T> T find(Class<T> entityClass, Object primaryKey, LockModeType lockMode, Map<String, Object> properties) {
+            return delegate.find(entityClass, primaryKey, lockMode, properties);
+        }
+
+        public <T> T getReference(Class<T> entityClass, Object primaryKey) {
+            return delegate.getReference(entityClass, primaryKey);
+        }
+
+        public void flush() {
+            delegate.flush();
+        }
+
+        public void setFlushMode(FlushModeType flushMode) {
+            delegate.setFlushMode(flushMode);
+        }
+
+        public FlushModeType getFlushMode() {
+            return delegate.getFlushMode();
+        }
+
+        public void lock(Object entity, LockModeType lockMode) {
+            delegate.lock(entity, lockMode);
+        }
+
+        public void lock(Object entity, LockModeType lockMode, Map<String, Object> properties) {
+            delegate.lock(entity, lockMode, properties);
+        }
+
+        public void refresh(Object entity) {
+            delegate.refresh(entity);
+        }
+
+        public void refresh(Object entity, Map<String, Object> properties) {
+            delegate.refresh(entity, properties);
+        }
+
+        public void refresh(Object entity, LockModeType lockMode) {
+            delegate.refresh(entity, lockMode);
+        }
+
+        public void refresh(Object entity, LockModeType lockMode, Map<String, Object> properties) {
+            delegate.refresh(entity, lockMode, properties);
+        }
+
+        public void clear() {
+            delegate.clear();
+        }
+
+        public void detach(Object entity) {
+            delegate.detach(entity);
+        }
+
+        public boolean contains(Object entity) {
+            return delegate.contains(entity);
+        }
+
+        public LockModeType getLockMode(Object entity) {
+            return delegate.getLockMode(entity);
+        }
+
+        public void setProperty(String propertyName, Object value) {
+            delegate.setProperty(propertyName, value);
+        }
+
+        public Map<String, Object> getProperties() {
+            return delegate.getProperties();
+        }
+
+        public Query createQuery(String qlString) {
+            return delegate.createQuery(qlString);
+        }
+
+        public <T> TypedQuery<T> createQuery(CriteriaQuery<T> criteriaQuery) {
+            return delegate.createQuery(criteriaQuery);
+        }
+
+        public Query createQuery(CriteriaUpdate updateQuery) {
+            return delegate.createQuery(updateQuery);
+        }
+
+        public Query createQuery(CriteriaDelete deleteQuery) {
+            return delegate.createQuery(deleteQuery);
+        }
+
+        public <T> TypedQuery<T> createQuery(String qlString, Class<T> resultClass) {
+            return delegate.createQuery(qlString, resultClass);
+        }
+
+        public Query createNamedQuery(String name) {
+            return delegate.createNamedQuery(name);
+        }
+
+        public <T> TypedQuery<T> createNamedQuery(String name, Class<T> resultClass) {
+            return delegate.createNamedQuery(name, resultClass);
+        }
+
+        public Query createNativeQuery(String sqlString) {
+            return delegate.createNativeQuery(sqlString);
+        }
+
+        public Query createNativeQuery(String sqlString, Class resultClass) {
+            return delegate.createNativeQuery(sqlString, resultClass);
+        }
+
+        public Query createNativeQuery(String sqlString, String resultSetMapping) {
+            return delegate.createNativeQuery(sqlString, resultSetMapping);
+        }
+
+        public StoredProcedureQuery createNamedStoredProcedureQuery(String name) {
+            return delegate.createNamedStoredProcedureQuery(name);
+        }
+
+        public StoredProcedureQuery createStoredProcedureQuery(String procedureName) {
+            return delegate.createStoredProcedureQuery(procedureName);
+        }
+
+        public StoredProcedureQuery createStoredProcedureQuery(String procedureName, Class... resultClasses) {
+            return delegate.createStoredProcedureQuery(procedureName, resultClasses);
+        }
+
+        public StoredProcedureQuery createStoredProcedureQuery(String procedureName, String... resultSetMappings) {
+            return delegate.createStoredProcedureQuery(procedureName, resultSetMappings);
+        }
+
+        public void joinTransaction() {
+            delegate.joinTransaction();
+        }
+
+        public boolean isJoinedToTransaction() {
+            return delegate.isJoinedToTransaction();
+        }
+
+        public <T> T unwrap(Class<T> cls) {
+            return delegate.unwrap(cls);
+        }
+
+        public Object getDelegate() {
+            return delegate.getDelegate();
+        }
+
+        public void close() {
+            log.info("[I229] close");
+            delegate.close();
+        }
+
+        public boolean isOpen() {
+            boolean isOpen = delegate.isOpen();
+            log.info("[I236] isOpen: " + isOpen);
+            return isOpen;
+        }
+
+        public EntityTransaction getTransaction() {
+            log.info("[I240] getTransaction()");
+            return delegate.getTransaction();
+        }
+
+        public EntityManagerFactory getEntityManagerFactory() {
+            return delegate.getEntityManagerFactory();
+        }
+
+        public CriteriaBuilder getCriteriaBuilder() {
+            return delegate.getCriteriaBuilder();
+        }
+
+        public Metamodel getMetamodel() {
+            return delegate.getMetamodel();
+        }
+
+        public <T> EntityGraph<T> createEntityGraph(Class<T> rootType) {
+            return delegate.createEntityGraph(rootType);
+        }
+
+        public EntityGraph<?> createEntityGraph(String graphName) {
+            return delegate.createEntityGraph(graphName);
+        }
+
+        public EntityGraph<?> getEntityGraph(String graphName) {
+            return delegate.getEntityGraph(graphName);
+        }
+
+        public <T> List<EntityGraph<? super T>> getEntityGraphs(Class<T> entityClass) {
+            return delegate.getEntityGraphs(entityClass);
+        }
+
+        public EntityManagerWrapper(EntityManager delegate) {
+            this.delegate = delegate;
+        }
+
+    }
+
+}
@@ -0,0 +1,125 @@
+    package org.baeldung.examples.olingo2;
+
+import java.io.IOException;
+
+import javax.persistence.EntityManager;
+import javax.persistence.EntityManagerFactory;
+import javax.persistence.EntityTransaction;
+import javax.servlet.ServletContext;
+import javax.servlet.http.HttpServletRequest;
+import javax.ws.rs.ApplicationPath;
+import javax.ws.rs.Path;
+import javax.ws.rs.container.ContainerRequestContext;
+import javax.ws.rs.container.ContainerRequestFilter;
+import javax.ws.rs.container.ContainerResponseContext;
+import javax.ws.rs.container.ContainerResponseFilter;
+import javax.ws.rs.core.Context;
+import javax.ws.rs.ext.Provider;
+
+import org.apache.olingo.odata2.api.ODataServiceFactory;
+import org.apache.olingo.odata2.core.rest.ODataRootLocator;
+import org.apache.olingo.odata2.core.rest.app.ODataApplication;
+import org.glassfish.jersey.server.ResourceConfig;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.stereotype.Component;
+
+/**
+ * Jersey JAX-RS configuration
+ * @author Philippe
+ *
+ */
+@Component
+@ApplicationPath("/odata")
+public class JerseyConfig extends ResourceConfig {
+    
+    
+    public JerseyConfig(CarsODataJPAServiceFactory serviceFactory, EntityManagerFactory emf) {        
+        
+        ODataApplication app = new ODataApplication();
+        
+        app
+          .getClasses()
+          .forEach( c -> {
+              // Avoid using the default RootLocator, as we want
+              // a Spring Managed one
+              if ( !ODataRootLocator.class.isAssignableFrom(c)) {
+                  register(c);
+              }
+          });
+        
+        register(new CarsRootLocator(serviceFactory)); 
+        register( new EntityManagerFilter(emf));
+    }
+    
+    /**
+     * This filter handles the EntityManager transaction lifecycle.
+     * @author Philippe
+     *
+     */
+    @Provider
+    public static class EntityManagerFilter implements ContainerRequestFilter, ContainerResponseFilter {
+
+        private static final Logger log = LoggerFactory.getLogger(EntityManagerFilter.class);
+        public static final String EM_REQUEST_ATTRIBUTE = EntityManagerFilter.class.getName() + "_ENTITY_MANAGER";
+
+        private final EntityManagerFactory emf;
+
+        @Context
+        private HttpServletRequest httpRequest;
+
+        public EntityManagerFilter(EntityManagerFactory emf) {
+            this.emf = emf;
+        }
+
+        @Override
+        public void filter(ContainerRequestContext ctx) throws IOException {
+            log.info("[I60] >>> filter");
+            EntityManager em = this.emf.createEntityManager();
+            httpRequest.setAttribute(EM_REQUEST_ATTRIBUTE, em);
+
+            // Start a new transaction unless we have a simple GET
+            if (!"GET".equalsIgnoreCase(ctx.getMethod())) {
+                em.getTransaction()
+                    .begin();
+            }
+        }
+
+        @Override
+        public void filter(ContainerRequestContext requestContext, ContainerResponseContext responseContext) throws IOException {
+
+            log.info("[I68] <<< filter");
+            EntityManager em = (EntityManager) httpRequest.getAttribute(EM_REQUEST_ATTRIBUTE);
+
+            if (!"GET".equalsIgnoreCase(requestContext.getMethod())) {
+                EntityTransaction t = em.getTransaction();
+                if (t.isActive()) {
+                    if (!t.getRollbackOnly()) {
+                        t.commit();
+                    }
+                }
+            }
+
+            em.close();
+
+        }
+
+    }
+
+    @Path("/")
+    public static class CarsRootLocator extends ODataRootLocator {
+
+        private CarsODataJPAServiceFactory serviceFactory;
+
+        public CarsRootLocator(CarsODataJPAServiceFactory serviceFactory) {
+            this.serviceFactory = serviceFactory;
+        }
+
+        @Override
+        public ODataServiceFactory getServiceFactory() {
+            return this.serviceFactory;
+        }
+
+    }
+
+}
@@ -0,0 +1,14 @@
+package org.baeldung.examples.olingo2;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.builder.SpringApplicationBuilder;
+import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;
+
+@SpringBootApplication
+public class Olingo2SampleApplication extends SpringBootServletInitializer {
+
+    public static void main(String[] args) {        
+        SpringApplication.run(Olingo2SampleApplication.class);
+    }
+}
@@ -0,0 +1,36 @@
+package org.baeldung.examples.olingo2.domain;
+
+import java.util.List;
+
+import javax.persistence.CascadeType;
+import javax.persistence.Column;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.OneToMany;
+import javax.persistence.Table;
+import javax.validation.constraints.NotNull;
+
+import lombok.Data;
+
+@Entity
+@Data
+@Table(name="car_maker")
+public class CarMaker {
+    
+    @Id
+    @GeneratedValue(strategy=GenerationType.IDENTITY)    
+    private Long id;
+    
+    @NotNull
+    @Column(name="name")
+    private String name;
+    
+    @OneToMany(mappedBy="maker",
+      orphanRemoval = true,
+      cascade=CascadeType.ALL)
+    private List<CarModel> models;
+    
+
+}
@@ -0,0 +1,38 @@
+package org.baeldung.examples.olingo2.domain;
+
+
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.JoinColumn;
+import javax.persistence.ManyToOne;
+import javax.persistence.Table;
+import javax.validation.constraints.NotNull;
+
+import lombok.Data;
+
+@Entity
+@Data
+@Table(name="car_model")
+public class CarModel {
+
+    @Id
+    @GeneratedValue(strategy=GenerationType.AUTO)
+    private Long id;
+    
+    @NotNull
+    private String name;
+    
+    @NotNull
+    private Integer year;
+    
+    @NotNull
+    private String sku;
+    
+    @ManyToOne(optional=false, fetch= FetchType.LAZY)
+    @JoinColumn(name="maker_fk")
+    private CarMaker maker;
+
+}
@@ -0,0 +1,12 @@
+server:
+  port: 8180
+  
+spring:
+  jersey:
+    application-path: /odata
+    
+  jpa:
+    show-sql: true
+    open-in-view: false
+    hibernate:
+      ddl-auto: update
@@ -0,0 +1,12 @@
+insert into car_maker(id,name) values (1,'Special Motors');
+insert into car_maker(id,name) values (2,'BWM');
+insert into car_maker(id,name) values (3,'Dolores');
+
+insert into car_model(id,maker_fk,name,sku,year) values(1,1,'Muze','SM001',2018);
+insert into car_model(id,maker_fk,name,sku,year) values(2,1,'Empada','SM002',2008);
+
+insert into car_model(id,maker_fk,name,sku,year) values(4,2,'BWM-100','BWM100',2008);
+insert into car_model(id,maker_fk,name,sku,year) values(5,2,'BWM-200','BWM200',2009);
+insert into car_model(id,maker_fk,name,sku,year) values(6,2,'BWM-300','BWM300',2008);
+
+alter sequence hibernate_sequence restart with 100;
@@ -0,0 +1,16 @@
+package org.baeldung.examples.olingo2;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit4.SpringRunner;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest
+public class Olingo2SampleApplicationTests {
+
+	@Test
+	public void contextLoads() {
+	}
+
+}
@@ -0,0 +1,256 @@
+{
+	"info": {
+		"_postman_id": "afa8e1e5-ab0e-4f1d-8b99-b7d1f091f975",
+		"name": "OLingo2 - Cars",
+		"schema": "https://schema.getpostman.com/json/collection/v2.0.0/collection.json"
+	},
+	"item": [
+		{
+			"name": "GET Metadata",
+			"request": {
+				"method": "GET",
+				"header": [],
+				"body": {
+					"mode": "raw",
+					"raw": ""
+				},
+				"url": "http://localhost:8080/odata/$metadata"
+			},
+			"response": []
+		},
+		{
+			"name": "GET All CarMakers",
+			"request": {
+				"method": "GET",
+				"header": [],
+				"body": {
+					"mode": "raw",
+					"raw": ""
+				},
+				"url": "http://localhost:8080/odata/CarMakers"
+			},
+			"response": []
+		},
+		{
+			"name": "GET Makers with Pagination",
+			"request": {
+				"method": "GET",
+				"header": [],
+				"body": {
+					"mode": "raw",
+					"raw": ""
+				},
+				"url": {
+					"raw": "http://localhost:8080/odata/CarMakers?$top=1&$orderby=Name&$skip=3",
+					"protocol": "http",
+					"host": [
+						"localhost"
+					],
+					"port": "8080",
+					"path": [
+						"odata",
+						"CarMakers"
+					],
+					"query": [
+						{
+							"key": "$top",
+							"value": "1"
+						},
+						{
+							"key": "$orderby",
+							"value": "Name"
+						},
+						{
+							"key": "$skip",
+							"value": "3"
+						}
+					]
+				}
+			},
+			"response": []
+		},
+		{
+			"name": "GET Makers and Models",
+			"request": {
+				"method": "GET",
+				"header": [],
+				"body": {
+					"mode": "raw",
+					"raw": ""
+				},
+				"url": {
+					"raw": "http://localhost:8080/odata/CarMakers?$expand=CarModelDetails",
+					"protocol": "http",
+					"host": [
+						"localhost"
+					],
+					"port": "8080",
+					"path": [
+						"odata",
+						"CarMakers"
+					],
+					"query": [
+						{
+							"key": "$expand",
+							"value": "CarModelDetails"
+						}
+					]
+				}
+			},
+			"response": []
+		},
+		{
+			"name": "GET Makers with filter",
+			"request": {
+				"method": "GET",
+				"header": [
+					{
+						"key": "Accept",
+						"value": "application/json",
+						"type": "text"
+					}
+				],
+				"body": {
+					"mode": "raw",
+					"raw": ""
+				},
+				"url": {
+					"raw": "http://localhost:8080/odata/CarMakers?$filter=Name eq 'BWM'&$expand=CarModelDetails",
+					"protocol": "http",
+					"host": [
+						"localhost"
+					],
+					"port": "8080",
+					"path": [
+						"odata",
+						"CarMakers"
+					],
+					"query": [
+						{
+							"key": "$filter",
+							"value": "Name eq 'BWM'"
+						},
+						{
+							"key": "$expand",
+							"value": "CarModelDetails"
+						}
+					]
+				}
+			},
+			"response": []
+		},
+		{
+			"name": "Create CarMaker",
+			"request": {
+				"method": "POST",
+				"header": [
+					{
+						"key": "Content-Type",
+						"name": "Content-Type",
+						"value": "application/atom+xml",
+						"type": "text"
+					},
+					{
+						"key": "Accept",
+						"value": "application/atom+xml",
+						"type": "text"
+					}
+				],
+				"body": {
+					"mode": "raw",
+					"raw": "<?xml version=\"1.0\" encoding=\"utf-8\" ?> \r\n<entry xmlns:d=\"http://schemas.microsoft.com/ado/2007/08/dataservices\"\r\n    xmlns:m=\"http://schemas.microsoft.com/ado/2007/08/dataservices/metadata\" \r\n    xmlns=\"http://www.w3.org/2005/Atom\">\r\n  <title type=\"text\"></title> \r\n  <updated>2019-04-02T21:36:47Z</updated>\r\n  <author> \r\n    <name /> \r\n  </author> \r\n  <category term=\"default.CarMaker\"\r\n      scheme=\"http://schemas.microsoft.com/ado/2007/08/dataservices/scheme\" /> \r\n  <content type=\"application/xml\"> \r\n    <m:properties>\r\n      <d:Name>Lucien</d:Name>\r\n    </m:properties> \r\n  </content> \r\n</entry>"
+				},
+				"url": "http://localhost:8080/odata/CarMakers"
+			},
+			"response": []
+		},
+		{
+			"name": "Create CarModel",
+			"request": {
+				"method": "POST",
+				"header": [
+					{
+						"key": "Content-Type",
+						"name": "Content-Type",
+						"type": "text",
+						"value": "application/atom+xml"
+					},
+					{
+						"key": "Accept",
+						"type": "text",
+						"value": "application/atom+xml"
+					}
+				],
+				"body": {
+					"mode": "raw",
+					"raw": "<?xml version=\"1.0\" encoding=\"utf-8\" ?> \r\n<entry xmlns:d=\"http://schemas.microsoft.com/ado/2007/08/dataservices\"\r\n    xmlns:m=\"http://schemas.microsoft.com/ado/2007/08/dataservices/metadata\" \r\n    xmlns=\"http://www.w3.org/2005/Atom\">\r\n  <title type=\"text\"></title> \r\n  <updated>2019-04-02T21:36:47Z</updated>\r\n  <author> \r\n    <name /> \r\n  </author> \r\n  <link href=\"CarModels(1L)/CarMakerDetails\" \r\n    rel=\"http://schemas.microsoft.com/ado/2007/08/dataservices/related/CarMakerDetails\" \r\n    title=\"CarMakerDetails\" \r\n    type=\"application/atom+xml;type=entry\"></link>  \r\n  <category term=\"default.CarModel\"\r\n      scheme=\"http://schemas.microsoft.com/ado/2007/08/dataservices/scheme\" /> \r\n  <content type=\"application/xml\"> \r\n    <m:properties>\r\n\t    <d:Name>Tata</d:Name>\r\n\t    <d:Sku>TT101</d:Sku>\r\n\t    <d:Year>2018</d:Year>\r\n    </m:properties> \r\n  </content> \r\n</entry>"
+				},
+				"url": "http://localhost:8080/odata/CarModels"
+			},
+			"response": []
+		},
+		{
+			"name": "Update CarMaker",
+			"request": {
+				"method": "PUT",
+				"header": [
+					{
+						"key": "Content-Type",
+						"name": "Content-Type",
+						"type": "text",
+						"value": "application/atom+xml"
+					},
+					{
+						"key": "Accept",
+						"type": "text",
+						"value": "application/atom+xml"
+					}
+				],
+				"body": {
+					"mode": "raw",
+					"raw": "<?xml version=\"1.0\" encoding=\"utf-8\" ?> \r\n<entry xmlns:d=\"http://schemas.microsoft.com/ado/2007/08/dataservices\"\r\n    xmlns:m=\"http://schemas.microsoft.com/ado/2007/08/dataservices/metadata\" \r\n    xmlns=\"http://www.w3.org/2005/Atom\">\r\n  <title type=\"text\"></title> \r\n  <updated>2019-04-02T21:36:47Z</updated>\r\n  <author> \r\n    <name /> \r\n  </author> \r\n  <category term=\"default.CarMaker\"\r\n      scheme=\"http://schemas.microsoft.com/ado/2007/08/dataservices/scheme\" /> \r\n  <content type=\"application/xml\"> \r\n    <m:properties>\r\n      <d:Id>5</d:Id>\r\n      <d:Name>KaiserWagen</d:Name>\r\n    </m:properties> \r\n  </content> \r\n</entry>"
+				},
+				"url": "http://localhost:8080/odata/CarMakers(5L)"
+			},
+			"response": []
+		},
+		{
+			"name": "All CarModels",
+			"request": {
+				"method": "GET",
+				"header": [],
+				"body": {
+					"mode": "raw",
+					"raw": ""
+				},
+				"url": "http://localhost:8080/odata/CarModels"
+			},
+			"response": []
+		},
+		{
+			"name": "Delete CarModel",
+			"request": {
+				"method": "DELETE",
+				"header": [
+					{
+						"key": "Content-Type",
+						"name": "Content-Type",
+						"type": "text",
+						"value": "application/atom+xml"
+					},
+					{
+						"key": "Accept",
+						"type": "text",
+						"value": "application/atom+xml"
+					}
+				],
+				"body": {
+					"mode": "raw",
+					"raw": ""
+				},
+				"url": "http://localhost:8080/odata/CarModels(100L)"
+			},
+			"response": []
+		}
+	]
+}
@@ -0,0 +1,29 @@
+HELP.md
+/target/
+!.mvn/wrapper/maven-wrapper.jar
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+/build/
+
+### VS Code ###
+.vscode/
@@ -0,0 +1,95 @@
+<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>2.1.3.RELEASE</version>
+		<relativePath /> <!-- lookup parent from repository -->
+	</parent>
+	<groupId>org.baeldung.examples.olingo4</groupId>
+	<artifactId>olingo4-sample</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<name>olingo4-sample</name>
+	<description>Sample Olingo 4 Project</description>
+
+	<properties>
+		<java.version>1.8</java.version>
+		<odata.version>4.5.0</odata.version>
+	</properties>
+
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-data-jpa</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-configuration-processor</artifactId>
+			<optional>true</optional>
+		</dependency>
+
+		<dependency>
+			<groupId>com.h2database</groupId>
+			<artifactId>h2</artifactId>
+			<scope>runtime</scope>
+		</dependency>
+
+		<dependency>
+			<groupId>org.projectlombok</groupId>
+			<artifactId>lombok</artifactId>
+			<optional>true</optional>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-web</artifactId>
+		</dependency>
+		
+		<dependency>
+			<groupId>org.apache.olingo</groupId>
+			<artifactId>odata-server-api</artifactId>
+			<version>${odata.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>org.apache.olingo</groupId>
+			<artifactId>odata-server-core</artifactId>
+			<version>${odata.version}</version>
+			<scope>runtime</scope>
+		</dependency>
+
+		<dependency>
+			<groupId>org.apache.olingo</groupId>
+			<artifactId>odata-commons-api</artifactId>
+			<version>${odata.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>org.apache.olingo</groupId>
+			<artifactId>odata-commons-core</artifactId>
+			<version>${odata.version}</version>
+		</dependency>
+		
+		<dependency>
+			<groupId>commons-beanutils</groupId>
+			<artifactId>commons-beanutils</artifactId>
+			<version>1.9.3</version>
+		</dependency>
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+			</plugin>
+		</plugins>
+	</build>
+
+</project>
@@ -0,0 +1,20 @@
+package org.baeldung.examples.olingo4;
+
+import org.apache.olingo.server.api.OData;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
+import org.springframework.stereotype.Component;
+
+/**
+ * Default implementation for ODataFactory 
+ * @author Philippe
+ *
+ */
+@Component
+public class DefaultODataFactory implements ODataFactory {
+
+    @Override
+    public OData newInstance() {
+        return OData.newInstance();
+    }
+
+}
@@ -0,0 +1,8 @@
+package org.baeldung.examples.olingo4;
+
+import org.apache.olingo.server.api.OData;
+
+public interface ODataFactory {
+
+    public OData newInstance();
+}
@@ -0,0 +1,8 @@
+package org.baeldung.examples.olingo4;
+
+import org.apache.olingo.server.api.ODataHttpHandler;
+
+public interface ODataHttpHandlerFactory {
+
+    ODataHttpHandler newInstance();
+}
@@ -0,0 +1,42 @@
+package org.baeldung.examples.olingo4;
+
+import java.util.Collections;
+import java.util.List;
+
+import org.apache.olingo.commons.api.edm.provider.CsdlEdmProvider;
+import org.apache.olingo.server.api.OData;
+import org.apache.olingo.server.api.ODataHttpHandler;
+import org.apache.olingo.server.api.ServiceMetadata;
+import org.apache.olingo.server.api.processor.Processor;
+
+import lombok.Builder;
+
+@Builder
+public class ODataHttpHandlerFactoryImpl implements ODataHttpHandlerFactory {
+    
+    
+    private final ODataFactory odataFactory;
+    private final CsdlEdmProvider edmProvider;
+    private final List<Processor> processors;
+
+    public ODataHttpHandlerFactoryImpl(ODataFactory odataFactory,CsdlEdmProvider edmProvider, List<Processor> processors) {
+        this.odataFactory = odataFactory;
+        this.edmProvider = edmProvider;
+        this.processors = processors;
+    }
+
+    @Override
+    public ODataHttpHandler newInstance() {
+        
+        OData odata = odataFactory.newInstance();
+        ServiceMetadata metadata = odata.createServiceMetadata(edmProvider, Collections.emptyList());
+        ODataHttpHandler handler = odata.createHandler(metadata);
+        
+        // Register all available processors
+        processors.forEach(p -> handler.register(p));
+        
+        
+        return handler;
+    }
+
+}
@@ -0,0 +1,35 @@
+package org.baeldung.examples.olingo4;
+
+import java.util.List;
+
+import javax.persistence.EntityManagerFactory;
+import javax.servlet.http.HttpServlet;
+
+import org.apache.olingo.commons.api.edm.provider.CsdlEdmProvider;
+import org.apache.olingo.server.api.processor.Processor;
+import org.baeldung.examples.olingo4.ODataHttpHandlerFactoryImpl.ODataHttpHandlerFactoryImplBuilder;
+import org.springframework.boot.web.servlet.ServletRegistrationBean;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+public class ODataServiceConfiguration {
+
+    @Bean
+    public ServletRegistrationBean<HttpServlet> odataServletRegistration(ODataHttpHandlerFactory factory) {
+        ServletRegistrationBean<HttpServlet> srb = 
+          new ServletRegistrationBean<>(new ODataServlet(factory), "/odata/*");
+        srb.setLoadOnStartup(1);
+        return srb;
+    }
+
+    @Bean
+    public ODataHttpHandlerFactory httpHandlerFactory(CsdlEdmProvider edmProvider, ODataFactory odataFactory, List<Processor> processors) {
+        return new ODataHttpHandlerFactoryImplBuilder()
+          .edmProvider(edmProvider)
+          .odataFactory(odataFactory)
+          .processors(processors)
+          .build();
+    }
+
+}
@@ -0,0 +1,38 @@
+/**
+ * 
+ */
+package org.baeldung.examples.olingo4;
+
+import java.io.IOException;
+
+import javax.persistence.EntityManager;
+import javax.persistence.EntityManagerFactory;
+import javax.persistence.EntityTransaction;
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServlet;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+
+import org.apache.olingo.server.api.ODataHttpHandler;
+
+/**
+ * @author Philippe
+ *
+ */
+public class ODataServlet extends HttpServlet {
+
+    private static final long serialVersionUID = 1L;
+    private final ODataHttpHandlerFactory odataHttpHandlerFactory;
+    
+    
+    public ODataServlet(ODataHttpHandlerFactory factory) {
+        this.odataHttpHandlerFactory = factory;
+    }
+
+    @Override
+    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+
+        ODataHttpHandler handler = odataHttpHandlerFactory.newInstance();
+        handler.process(req, resp);
+    }
+}
@@ -0,0 +1,13 @@
+package org.baeldung.examples.olingo4;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class Olingo4SampleApplication {
+
+    public static void main(String[] args) {
+        SpringApplication.run(Olingo4SampleApplication.class, args);
+    }
+
+}
@@ -0,0 +1,36 @@
+package org.baeldung.examples.olingo4.domain;
+
+import java.util.List;
+
+import javax.persistence.CascadeType;
+import javax.persistence.Column;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.OneToMany;
+import javax.persistence.Table;
+import javax.validation.constraints.NotNull;
+
+import lombok.Data;
+
+@Entity
+@Data
+@Table(name="car_maker")
+public class CarMaker {
+    
+    @Id
+    @GeneratedValue(strategy=GenerationType.IDENTITY)    
+    private Long id;
+    
+    @NotNull
+    @Column(name="name")
+    private String name;
+    
+    @OneToMany(mappedBy="maker",
+      orphanRemoval = true,
+      cascade=CascadeType.ALL)
+    private List<CarModel> models;
+    
+
+}
@@ -0,0 +1,38 @@
+package org.baeldung.examples.olingo4.domain;
+
+
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.JoinColumn;
+import javax.persistence.ManyToOne;
+import javax.persistence.Table;
+import javax.validation.constraints.NotNull;
+
+import lombok.Data;
+
+@Entity
+@Data
+@Table(name="car_model")
+public class CarModel {
+
+    @Id
+    @GeneratedValue(strategy=GenerationType.AUTO)
+    private Long id;
+    
+    @NotNull
+    private String name;
+    
+    @NotNull
+    private Integer year;
+    
+    @NotNull
+    private String sku;
+    
+    @ManyToOne(optional=false, fetch= FetchType.EAGER   )
+    @JoinColumn(name="maker_fk")
+    private CarMaker maker;
+
+}
@@ -0,0 +1,46 @@
+package org.baeldung.examples.olingo4.edm;
+
+import java.util.Collections;
+import java.util.Date;
+import java.util.Map;
+import java.util.UUID;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+import java.sql.Time;
+import java.util.AbstractMap.SimpleEntry;
+
+import org.apache.olingo.commons.api.edm.EdmPrimitiveTypeKind;
+import org.springframework.stereotype.Component;
+
+@Component
+public class EdmTypeMapper {
+
+    public EdmPrimitiveTypeKind java2edm(Class<?> clazz) {
+        EdmPrimitiveTypeKind result = java2edm.get(clazz);
+        if ( result == null ) {
+            throw new IllegalArgumentException("[E19] Unsupported class mapping: class=" + clazz);
+        }
+        else {
+            return result;
+        }
+    }
+    
+    // Static map used generate attribute metadada based on Java types
+    static Map<Class<?>,EdmPrimitiveTypeKind> java2edm = Collections
+      .unmodifiableMap(Stream.of(
+        new SimpleEntry<>(Boolean.class,EdmPrimitiveTypeKind.Boolean),
+        new SimpleEntry<>(Byte.class,EdmPrimitiveTypeKind.SByte),
+        new SimpleEntry<>(Date.class,EdmPrimitiveTypeKind.Date),
+        new SimpleEntry<>(Time.class,EdmPrimitiveTypeKind.TimeOfDay),
+        new SimpleEntry<>(Number.class,EdmPrimitiveTypeKind.Decimal),
+        new SimpleEntry<>(Float.class,EdmPrimitiveTypeKind.Single),
+        new SimpleEntry<>(Double.class,EdmPrimitiveTypeKind.Double),
+        new SimpleEntry<>(UUID.class,EdmPrimitiveTypeKind.Guid),
+        new SimpleEntry<>(Short.class,EdmPrimitiveTypeKind.Int16),
+        new SimpleEntry<>(Integer.class,EdmPrimitiveTypeKind.Int32),
+        new SimpleEntry<>(Long.class,EdmPrimitiveTypeKind.Int64),
+        new SimpleEntry<>(String.class,EdmPrimitiveTypeKind.String)
+      
+      ).collect(Collectors.toMap((e)-> e.getKey(),(e)-> e.getValue())));
+
+}
@@ -0,0 +1,269 @@
+package org.baeldung.examples.olingo4.edm;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.stream.Collectors;
+
+import javax.persistence.EntityManagerFactory;
+import javax.persistence.metamodel.Attribute.PersistentAttributeType;
+import javax.persistence.metamodel.EntityType;
+import javax.persistence.metamodel.Metamodel;
+import javax.persistence.metamodel.PluralAttribute;
+import javax.persistence.metamodel.SingularAttribute;
+
+import org.apache.olingo.commons.api.edm.FullQualifiedName;
+import org.apache.olingo.commons.api.edm.provider.CsdlAbstractEdmProvider;
+import org.apache.olingo.commons.api.edm.provider.CsdlEntityContainer;
+import org.apache.olingo.commons.api.edm.provider.CsdlEntityContainerInfo;
+import org.apache.olingo.commons.api.edm.provider.CsdlEntitySet;
+import org.apache.olingo.commons.api.edm.provider.CsdlEntityType;
+import org.apache.olingo.commons.api.edm.provider.CsdlNavigationProperty;
+import org.apache.olingo.commons.api.edm.provider.CsdlProperty;
+import org.apache.olingo.commons.api.edm.provider.CsdlPropertyRef;
+import org.apache.olingo.commons.api.edm.provider.CsdlSchema;
+import org.apache.olingo.commons.api.ex.ODataException;
+import org.springframework.stereotype.Component;
+
+@Component
+public class JpaEdmProvider extends CsdlAbstractEdmProvider {
+
+    EntityManagerFactory emf;
+
+    //
+    private EdmTypeMapper typeMapper;
+
+    // Service Namespace
+    public static final String NAMESPACE = "Baeldung.OData";
+
+    // EDM Container
+    public static final String CONTAINER_NAME = "Cars";
+    public static final FullQualifiedName CONTAINER = new FullQualifiedName(NAMESPACE, CONTAINER_NAME);
+    
+    // Caches of OData types by it fully qualified name
+    private Map<FullQualifiedName, CsdlEntityType> cdslName2Type = new HashMap<>();
+
+    public JpaEdmProvider(EntityManagerFactory emf, EdmTypeMapper mapper) {
+        this.emf = emf;
+        this.typeMapper = mapper;
+    }
+
+    /* (non-Javadoc)
+     * @see org.apache.olingo.commons.api.edm.provider.CsdlAbstractEdmProvider#getEntitySet(org.apache.olingo.commons.api.edm.FullQualifiedName, java.lang.String)
+     */
+    @Override
+    public CsdlEntitySet getEntitySet(FullQualifiedName entityContainer, String entitySetName) throws ODataException {
+
+        if (entityContainer.equals(CONTAINER)) {
+
+            EntityType<?> e = emf.getMetamodel()
+                .getEntities()
+                .stream()
+                .filter((ent) -> (ent.getName() + "s")
+                    .equals(entitySetName))
+                .findFirst()
+                .orElse(null);
+
+            if (e != null) {
+                CsdlEntitySet entitySet = new CsdlEntitySet();
+                entitySet
+                  .setName(entitySetName)
+                  .setType(new FullQualifiedName(NAMESPACE, e.getName()));
+                return entitySet;
+            }
+        }
+
+        return null;
+    }
+
+    /* (non-Javadoc)
+     * @see org.apache.olingo.commons.api.edm.provider.CsdlAbstractEdmProvider#getEntityContainerInfo(org.apache.olingo.commons.api.edm.FullQualifiedName)
+     */
+    @Override
+    public CsdlEntityContainerInfo getEntityContainerInfo(FullQualifiedName entityContainerName) throws ODataException {
+
+        // This method is invoked when displaying the Service Document at e.g. http://localhost:8080/DemoService/DemoService.svc
+        if (entityContainerName == null || entityContainerName.equals(CONTAINER)) {
+            CsdlEntityContainerInfo entityContainerInfo = new CsdlEntityContainerInfo();
+            entityContainerInfo.setContainerName(CONTAINER);
+            return entityContainerInfo;
+        }
+
+        return null;
+    }
+
+    /* (non-Javadoc)
+     * @see org.apache.olingo.commons.api.edm.provider.CsdlAbstractEdmProvider#getSchemas()
+     */
+    @Override
+    public List<CsdlSchema> getSchemas() throws ODataException {
+        // create Schema
+        CsdlSchema schema = new CsdlSchema();
+        schema.setNamespace(NAMESPACE);
+
+        // add EntityTypes
+        List<CsdlEntityType> entityTypes = emf.getMetamodel()
+            .getEntities()
+            .stream()
+            .map((e) -> {
+                try {
+                    return getEntityType(new FullQualifiedName(NAMESPACE, e.getName()));
+                } catch (ODataException oe) {
+                    throw new RuntimeException(oe);
+                }
+            })
+            .collect(Collectors.toList());
+
+        schema.setEntityTypes(entityTypes);
+
+        // add EntityContainer
+        schema.setEntityContainer(getEntityContainer());
+
+        // finally
+        List<CsdlSchema> schemas = new ArrayList<CsdlSchema>();
+        schemas.add(schema);
+
+        return schemas;
+    }
+
+    /* (non-Javadoc)
+     * @see org.apache.olingo.commons.api.edm.provider.CsdlAbstractEdmProvider#getEntityContainer()
+     */
+    @Override
+    public CsdlEntityContainer getEntityContainer() throws ODataException {
+        
+        
+        // add EntityTypes
+        List<CsdlEntitySet> entitySets = emf.getMetamodel()
+            .getEntities()
+            .stream()
+            .map((e) -> {
+                try {
+                    // Here we use a simple mapping strategy to map entity types to entity set names:
+                    return getEntitySet(CONTAINER, e.getName() + "s");
+                } catch (ODataException oe) {
+                    throw new RuntimeException(oe);
+                }
+            })
+            .collect(Collectors.toList());
+        
+        // create EntityContainer
+        CsdlEntityContainer entityContainer = new CsdlEntityContainer();
+        entityContainer.setName(CONTAINER_NAME);
+        entityContainer.setEntitySets(entitySets);
+
+        return entityContainer;
+    }
+
+    @Override
+    public CsdlEntityType getEntityType(FullQualifiedName entityTypeName) throws ODataException {
+        
+        CsdlEntityType result = cdslName2Type.get(entityTypeName);
+        if ( result != null ) {
+            return result;
+        }
+
+        Metamodel mm = emf.getMetamodel();
+        result = mm.getEntities()
+            .stream()
+            .filter(et -> entityTypeName.equals(new FullQualifiedName(NAMESPACE, et.getName())))
+            .map(et -> buildODataType(et))
+            .findFirst()
+            .orElse(null);
+
+        // save for future use
+        cdslName2Type.put(entityTypeName, result);
+        return result;
+        
+    }
+
+    /**
+     * Maps a JPA type to its OData counterpart.
+     * @param et
+     * @return
+     */
+    protected CsdlEntityType buildODataType(EntityType<?> et) {
+
+        CsdlEntityType result = new CsdlEntityType();
+        result.setName(et.getName());
+
+        // Process simple properties
+        List<CsdlProperty> properties = et.getDeclaredSingularAttributes()
+            .stream()
+            .filter(attr -> attr.getPersistentAttributeType() == PersistentAttributeType.BASIC)
+            .map(attr -> buildBasicAttribute(et, attr))
+            .collect(Collectors.toList());
+
+        result.setProperties(properties);
+
+        // Process Ids
+        List<CsdlPropertyRef> ids = et.getDeclaredSingularAttributes()
+            .stream()
+            .filter(attr -> attr.getPersistentAttributeType() == PersistentAttributeType.BASIC && attr.isId())
+            .map(attr -> buildRefAttribute(et, attr))
+            .collect(Collectors.toList());
+
+        result.setKey(ids);
+
+        // Process 1:N navs
+        List<CsdlNavigationProperty> navs = et.getDeclaredPluralAttributes()
+            .stream()
+            .map(attr -> buildNavAttribute(et, attr))
+            .collect(Collectors.toList());
+        result.setNavigationProperties(navs);
+        
+        // Process N:1 navs
+        List<CsdlNavigationProperty> navs2 = et.getDeclaredSingularAttributes()
+            .stream()
+            .filter(attr -> attr.getPersistentAttributeType() == PersistentAttributeType.MANY_TO_ONE)
+            .map(attr -> buildNavAttribute(et, attr))
+            .collect(Collectors.toList());
+
+        result.getNavigationProperties().addAll(navs2);
+        
+
+        return result;
+    }
+
+    private CsdlProperty buildBasicAttribute(EntityType<?> et, SingularAttribute<?, ?> attr) {
+
+        CsdlProperty p = new CsdlProperty().setName(attr.getName())
+            .setType(typeMapper.java2edm(attr.getJavaType())
+                .getFullQualifiedName())
+            .setNullable(et.getDeclaredSingularAttribute(attr.getName())
+                .isOptional());
+
+        return p;
+    }
+
+    private CsdlPropertyRef buildRefAttribute(EntityType<?> et, SingularAttribute<?, ?> attr) {
+
+        CsdlPropertyRef p = new CsdlPropertyRef().setName(attr.getName());
+
+        return p;
+    }
+
+    // Build NavProperty for 1:N or M:N associations
+    private CsdlNavigationProperty buildNavAttribute(EntityType<?> et, PluralAttribute<?, ?, ?> attr) {
+
+        CsdlNavigationProperty p = new CsdlNavigationProperty().setName(attr.getName())
+            .setType(new FullQualifiedName(NAMESPACE, attr.getBindableJavaType().getSimpleName()))
+            .setCollection(true)
+            .setNullable(false); 
+
+        return p;
+    }
+
+    // Build NavProperty for N:1 associations
+    private CsdlNavigationProperty buildNavAttribute(EntityType<?> et, SingularAttribute<?, ?> attr) {
+
+        CsdlNavigationProperty p = new CsdlNavigationProperty().setName(attr.getName())
+            .setType(new FullQualifiedName(NAMESPACE, attr.getBindableJavaType().getSimpleName()))
+            .setCollection(false)
+            .setNullable(attr.isOptional());
+
+        return p;
+    }
+    
+}
@@ -0,0 +1,161 @@
+package org.baeldung.examples.olingo4.processor;
+
+import java.io.ByteArrayInputStream;
+import java.io.InputStream;
+import java.lang.reflect.InvocationTargetException;
+import java.net.URI;
+import java.net.URISyntaxException;
+import java.util.Collection;
+import java.util.List;
+
+import javax.persistence.EntityManagerFactory;
+import javax.persistence.metamodel.EntityType;
+import javax.persistence.metamodel.SingularAttribute;
+
+import org.apache.commons.beanutils.PropertyUtils;
+import org.apache.olingo.commons.api.data.ContextURL;
+import org.apache.olingo.commons.api.data.Entity;
+import org.apache.olingo.commons.api.data.EntityCollection;
+import org.apache.olingo.commons.api.data.Property;
+import org.apache.olingo.commons.api.data.ValueType;
+import org.apache.olingo.commons.api.edm.EdmEntitySet;
+import org.apache.olingo.commons.api.edm.EdmEntityType;
+import org.apache.olingo.commons.api.edm.EdmNavigationProperty;
+import org.apache.olingo.commons.api.ex.ODataRuntimeException;
+import org.apache.olingo.commons.api.format.ContentType;
+import org.apache.olingo.commons.api.http.HttpHeader;
+import org.apache.olingo.commons.api.http.HttpStatusCode;
+import org.apache.olingo.server.api.OData;
+import org.apache.olingo.server.api.ODataApplicationException;
+import org.apache.olingo.server.api.ODataLibraryException;
+import org.apache.olingo.server.api.ODataRequest;
+import org.apache.olingo.server.api.ODataResponse;
+import org.apache.olingo.server.api.ServiceMetadata;
+import org.apache.olingo.server.api.processor.CountEntityCollectionProcessor;
+import org.apache.olingo.server.api.processor.EntityCollectionProcessor;
+import org.apache.olingo.server.api.serializer.EntityCollectionSerializerOptions;
+import org.apache.olingo.server.api.serializer.ODataSerializer;
+import org.apache.olingo.server.api.serializer.SerializerResult;
+import org.apache.olingo.server.api.uri.UriInfo;
+import org.apache.olingo.server.api.uri.UriParameter;
+import org.apache.olingo.server.api.uri.UriResource;
+import org.apache.olingo.server.api.uri.UriResourceEntitySet;
+import org.baeldung.examples.olingo4.repository.RepositoryRegistry;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Component;
+
+@Component
+public class JpaEntityCollectionProcessor implements CountEntityCollectionProcessor {
+
+    private OData odata;
+    private ServiceMetadata serviceMetadata;
+    private EntityManagerFactory emf;
+    private RepositoryRegistry repositoryRegistry;
+    private JpaEntityMapper entityMapper;
+
+    public JpaEntityCollectionProcessor(EntityManagerFactory emf, RepositoryRegistry repositoryRegistry, JpaEntityMapper entityMapper) {
+        this.emf = emf;
+        this.repositoryRegistry = repositoryRegistry;
+        this.entityMapper = entityMapper;
+    }
+
+    @Override
+    public void init(OData odata, ServiceMetadata serviceMetadata) {
+        this.odata = odata;
+        this.serviceMetadata = serviceMetadata;
+    }
+
+    @Override
+    public void readEntityCollection(ODataRequest request, ODataResponse response, UriInfo uriInfo, ContentType responseFormat) throws ODataApplicationException, ODataLibraryException {
+
+        // 1st we have retrieve the requested EntitySet from the uriInfo object (representation of the parsed service URI)
+        List<UriResource> resourcePaths = uriInfo.getUriResourceParts();
+        UriResourceEntitySet uriResourceEntitySet = (UriResourceEntitySet) resourcePaths.get(0); // in our example, the first segment is the EntitySet
+        EdmEntitySet edmEntitySet = uriResourceEntitySet.getEntitySet();
+
+        // 2nd: fetch the data from backend for this requested EntitySetName
+        // it has to be delivered as EntitySet object
+        EntityCollection entitySet = getData(edmEntitySet, uriInfo);
+
+        // 3rd: create a serializer based on the requested format (json)
+        ODataSerializer serializer = odata.createSerializer(responseFormat);
+
+        // 4th: Now serialize the content: transform from the EntitySet object to InputStream
+        EdmEntityType edmEntityType = edmEntitySet.getEntityType();
+        ContextURL contextUrl = ContextURL.with()
+            .entitySet(edmEntitySet)
+            .build();
+
+        final String id = request.getRawBaseUri() + "/" + edmEntitySet.getName();
+        EntityCollectionSerializerOptions opts = EntityCollectionSerializerOptions.with()
+            .id(id)
+            .contextURL(contextUrl)
+            .build();
+        SerializerResult serializerResult = serializer.entityCollection(serviceMetadata, edmEntityType, entitySet, opts);
+        InputStream serializedContent = serializerResult.getContent();
+
+        // Finally: configure the response object: set the body, headers and status code
+        response.setContent(serializedContent);
+        response.setStatusCode(HttpStatusCode.OK.getStatusCode());
+        response.setHeader(HttpHeader.CONTENT_TYPE, responseFormat.toContentTypeString());
+
+    }
+
+    @Override
+    public void countEntityCollection(ODataRequest request, ODataResponse response, UriInfo uriInfo) throws ODataApplicationException, ODataLibraryException {
+
+        // 1st we have retrieve the requested EntitySet from the uriInfo object (representation of the parsed service URI)
+        List<UriResource> resourcePaths = uriInfo.getUriResourceParts();
+        UriResourceEntitySet uriResourceEntitySet = (UriResourceEntitySet) resourcePaths.get(0); // in our example, the first segment is the EntitySet
+        EdmEntitySet edmEntitySet = uriResourceEntitySet.getEntitySet();
+
+        // 2nd: fetch the data from backend for this requested EntitySetName
+        Long count = getCount(edmEntitySet, uriInfo);
+
+        // Finally: configure the response object: set the body, headers and status code
+        response.setContent(new ByteArrayInputStream(count.toString().getBytes()));
+        response.setStatusCode(HttpStatusCode.OK.getStatusCode());
+        response.setHeader(HttpHeader.CONTENT_TYPE, "text/plain");
+
+    }
+
+    /**
+     * Helper method to retrieve all entities of an entity set from an the backend database
+     * @param edmEntitySet
+     * @param uriInfo
+     * @return
+     */
+    protected EntityCollection getData(EdmEntitySet edmEntitySet, UriInfo uriInfo) {
+
+        EdmEntityType type = edmEntitySet.getEntityType();
+        JpaRepository<?, ?> repo = (JpaRepository<?, ?>)repositoryRegistry.getRepositoryForEntity(type);
+        EntityCollection result = new EntityCollection();
+
+        repo.findAll()
+          .stream()
+          .forEach((it) -> result.getEntities()
+          .add(entityMapper.map2entity(edmEntitySet, it)));
+
+        return result;
+    }
+
+
+    /**
+     * Helper method to get the total size of an entity set
+     * @param edmEntitySet
+     * @param uriInfo
+     * @return
+     */
+    protected Long getCount(EdmEntitySet edmEntitySet, UriInfo uriInfo) {
+        
+        EdmEntityType type = edmEntitySet.getEntityType();
+        JpaRepository<?, ?> repo = (JpaRepository<?, ?>)repositoryRegistry.getRepositoryForEntity(type);
+        EntityCollection result = new EntityCollection();
+
+        return repo.count();
+    }
+    
+    
+
+
+}
@@ -0,0 +1,93 @@
+/**
+ * 
+ */
+package org.baeldung.examples.olingo4.processor;
+
+import java.lang.reflect.InvocationTargetException;
+import java.net.URI;
+import java.net.URISyntaxException;
+
+import javax.persistence.EntityManagerFactory;
+import javax.persistence.metamodel.EntityType;
+
+import org.apache.commons.beanutils.PropertyUtils;
+import org.apache.olingo.commons.api.data.Entity;
+import org.apache.olingo.commons.api.data.Property;
+import org.apache.olingo.commons.api.data.ValueType;
+import org.apache.olingo.commons.api.edm.EdmEntitySet;
+import org.apache.olingo.commons.api.ex.ODataRuntimeException;
+import org.springframework.stereotype.Component;
+
+/**
+ * <p>Helper class that converts a JPA entity into an OData entity using
+ * available metadata from the JPA's EntityManagerFactory.</p>
+ * 
+ * @author Philippe
+ *
+ */
+@Component
+public class JpaEntityMapper {
+    
+    private EntityManagerFactory emf;
+
+    public JpaEntityMapper(EntityManagerFactory emf) {
+        this.emf = emf;
+    }
+    
+    
+    public Entity map2entity(EdmEntitySet edmEntitySet, Object entry) {
+
+        EntityType<?> et = emf.getMetamodel()
+            .entity(entry.getClass());
+
+
+        Entity e = new Entity();
+        try {
+            et.getDeclaredSingularAttributes().stream()
+              .forEach( (attr) -> {
+                 if ( !attr.isAssociation()) {
+                     Object v = getPropertyValue(entry,attr.getName());
+                     Property p = new Property(null, attr.getName(),ValueType.PRIMITIVE,v);
+                     e.addProperty(p);
+
+                     if ( attr.isId()) {
+                         e.setId(createId(edmEntitySet.getName(),v));                     
+                     }                     
+                 }                 
+              });
+        } catch (Exception ex) {
+            throw new ODataRuntimeException("[E141] Unable to create OData entity", ex);
+        }
+
+        return e;
+    }
+    
+    
+    public Object getPropertyValue(Object entry, String name) {
+        try {
+            return PropertyUtils.getProperty(entry,name);
+        } catch (IllegalAccessException | InvocationTargetException | NoSuchMethodException e) {
+            throw new ODataRuntimeException("[E141] Unable to read property from entity, property=" + name, e);
+        }
+    }
+    
+    public void setPropertyValue(Object entry, String name,Object value) {
+        try {
+            PropertyUtils.setProperty(entry,name,value);
+        } catch (IllegalAccessException | InvocationTargetException | NoSuchMethodException e) {
+            throw new ODataRuntimeException("[E141] Unable to read property from entity, property=" + name, e);
+        }
+    }
+    
+
+    private URI createId(String entitySetName, Object id)  {
+        try {
+            return new URI(entitySetName + "(" + String.valueOf(id) + ")");
+        } catch (URISyntaxException e) {
+            throw new ODataRuntimeException("[E177] Unable to create URI", e);
+        }
+    }
+    
+
+
+}
--- a/Show More
+++ b/Show More