portable way to generate the identifier for managed entity with either sequene generator or identity generator( if the database does not support former one)

jpa-one-to-many-demo/Hibernate one to many mapping example.postman_collection.json

@@ -0,0 +1,183 @@
+{
+	"id": "50f06778-83f3-3359-8bc5-cc3d0bdf582d",
+	"name": "Hibernate one to many mapping example",
+	"description": "",
+	"order": [
+		"15826d80-cf0a-78c9-1acf-36fef67d89fc",
+		"095e803e-c84e-6e66-c785-83930184de23",
+		"1086cdf7-fb9e-305a-1118-b4a1e3335453",
+		"df740598-560e-5b22-8c65-f719411d1d24"
+	],
+	"folders": [],
+	"folders_order": [],
+	"timestamp": 1569687636029,
+	"owner": "2037757",
+	"public": false,
+	"requests": [
+		{
+			"id": "095e803e-c84e-6e66-c785-83930184de23",
+			"headers": "Content-Type: application/json\n",
+			"headerData": [
+				{
+					"key": "Content-Type",
+					"value": "application/json",
+					"description": "",
+					"enabled": true
+				}
+			],
+			"url": "localhost:8080/v1/posts?page=0&size=3&sort=createdAt,desc",
+			"queryParams": [
+				{
+					"key": "page",
+					"value": "0",
+					"equals": true,
+					"description": "",
+					"enabled": true
+				},
+				{
+					"key": "size",
+					"value": "3",
+					"equals": true,
+					"description": "",
+					"enabled": true
+				},
+				{
+					"key": "sort",
+					"value": "createdAt,desc",
+					"equals": true,
+					"description": "",
+					"enabled": true
+				}
+			],
+			"preRequestScript": null,
+			"pathVariables": {},
+			"pathVariableData": [],
+			"method": "GET",
+			"data": null,
+			"dataMode": "params",
+			"version": 2,
+			"tests": null,
+			"currentHelper": "normal",
+			"helperAttributes": {},
+			"time": 1569689480899,
+			"name": "Retrieve all posts",
+			"description": "",
+			"collectionId": "50f06778-83f3-3359-8bc5-cc3d0bdf582d",
+			"responses": []
+		},
+		{
+			"id": "1086cdf7-fb9e-305a-1118-b4a1e3335453",
+			"headers": "Content-Type: application/json\n",
+			"headerData": [
+				{
+					"key": "Content-Type",
+					"value": "application/json",
+					"description": "",
+					"enabled": true
+				}
+			],
+			"url": "localhost:8080/v1/posts/1/comments",
+			"queryParams": [],
+			"pathVariables": {},
+			"pathVariableData": [],
+			"preRequestScript": null,
+			"method": "POST",
+			"collectionId": "50f06778-83f3-3359-8bc5-cc3d0bdf582d",
+			"data": [],
+			"dataMode": "raw",
+			"name": "Create comment",
+			"description": "",
+			"descriptionFormat": "html",
+			"time": 1569689148814,
+			"version": 2,
+			"responses": [],
+			"tests": null,
+			"currentHelper": "normal",
+			"helperAttributes": {},
+			"rawModeData": "{\n\t\"text\": \"it's nice post\"\n}"
+		},
+		{
+			"id": "15826d80-cf0a-78c9-1acf-36fef67d89fc",
+			"headers": "Content-Type: application/json\n",
+			"headerData": [
+				{
+					"key": "Content-Type",
+					"value": "application/json",
+					"description": "",
+					"enabled": true
+				}
+			],
+			"url": "localhost:8080/v1/posts",
+			"queryParams": [],
+			"pathVariables": {},
+			"pathVariableData": [],
+			"preRequestScript": null,
+			"method": "POST",
+			"collectionId": "50f06778-83f3-3359-8bc5-cc3d0bdf582d",
+			"data": [],
+			"dataMode": "raw",
+			"name": "Create post",
+			"description": "",
+			"descriptionFormat": "html",
+			"time": 1569687903992,
+			"version": 2,
+			"responses": [],
+			"tests": null,
+			"currentHelper": "normal",
+			"helperAttributes": {},
+			"rawModeData": "{\n\t\"title\": \"post 1\",\n\t\"description\": \"post 1 description\",\n\t\"content\": \"post 1 content\"\n}"
+		},
+		{
+			"id": "df740598-560e-5b22-8c65-f719411d1d24",
+			"headers": "Content-Type: application/json\n",
+			"headerData": [
+				{
+					"key": "Content-Type",
+					"value": "application/json",
+					"description": "",
+					"enabled": true
+				}
+			],
+			"url": "localhost:8080/v1/posts/1/comments?page=0&size=3&sort=createdAt,desc",
+			"queryParams": [
+				{
+					"key": "page",
+					"value": "0",
+					"equals": true,
+					"description": "",
+					"enabled": true
+				},
+				{
+					"key": "size",
+					"value": "3",
+					"equals": true,
+					"description": "",
+					"enabled": true
+				},
+				{
+					"key": "sort",
+					"value": "createdAt,desc",
+					"equals": true,
+					"description": "",
+					"enabled": true
+				}
+			],
+			"pathVariables": {},
+			"pathVariableData": [],
+			"preRequestScript": null,
+			"method": "GET",
+			"collectionId": "50f06778-83f3-3359-8bc5-cc3d0bdf582d",
+			"data": null,
+			"dataMode": "params",
+			"name": "Retrieve all comments of a post",
+			"description": "",
+			"descriptionFormat": "html",
+			"time": 1569689513143,
+			"version": 2,
+			"responses": [],
+			"tests": null,
+			"currentHelper": "normal",
+			"helperAttributes": {}
+		}
+	]
+}

jpa-one-to-many-demo/pom.xml

@@ -38,6 +38,13 @@
 			<groupId>mysql</groupId>
 			<artifactId>mysql-connector-java</artifactId>
 			<scope>runtime</scope>
+			<version>8.0.13</version>
+		</dependency>
+		<!-- https://mvnrepository.com/artifact/org.hibernate/hibernate-core -->
+		<dependency>
+			<groupId>org.hibernate</groupId>
+			<artifactId>hibernate-core</artifactId>
+			<version>5.3.1.Final</version>
 		</dependency>
 		<dependency>
 			<groupId>org.springframework.boot</groupId>

jpa-one-to-many-demo/src/main/java/com/example/jpa/JpaOneToManyDemoApplication.java → jpa-one-to-many-demo/src/main/java/com/amit/jpa/JpaOneToManyDemoApplication.java

@@ -1,9 +1,13 @@
-package com.example.jpa;
+package com.amit.jpa;
 
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 import org.springframework.data.jpa.repository.config.EnableJpaAuditing;
-
+/**
+*
+* @author Amit Patil
+*
+**/
 @SpringBootApplication
 @EnableJpaAuditing
 public class JpaOneToManyDemoApplication {

jpa-one-to-many-demo/src/main/java/com/example/jpa/controller/CommentController.java → jpa-one-to-many-demo/src/main/java/com/amit/jpa/controller/CommentController.java

@@ -1,18 +1,24 @@
-package com.example.jpa.controller;
+package com.amit.jpa.controller;
+
+import com.amit.jpa.exception.ResourceNotFoundException;
+import com.amit.jpa.model.Comment;
+import com.amit.jpa.repository.CommentRepository;
+import com.amit.jpa.repository.PostRepository;
 
-import com.example.jpa.exception.ResourceNotFoundException;
-import com.example.jpa.model.Comment;
-import com.example.jpa.repository.CommentRepository;
-import com.example.jpa.repository.PostRepository;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Pageable;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.*;
 
 import javax.validation.Valid;
-
+/**
+*
+* @author Amit Patil
+*
+**/
 @RestController
+@RequestMapping("/v1")
 public class CommentController {
 
     @Autowired

jpa-one-to-many-demo/src/main/java/com/example/jpa/controller/PostController.java → jpa-one-to-many-demo/src/main/java/com/amit/jpa/controller/PostController.java

@@ -1,17 +1,23 @@
-package com.example.jpa.controller;
+package com.amit.jpa.controller;
+
+import com.amit.jpa.exception.ResourceNotFoundException;
+import com.amit.jpa.model.Post;
+import com.amit.jpa.repository.PostRepository;
 
-import com.example.jpa.exception.ResourceNotFoundException;
-import com.example.jpa.model.Post;
-import com.example.jpa.repository.PostRepository;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Pageable;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.*;
 
 import javax.validation.Valid;
-
+/**
+*
+* @author Amit Patil
+*
+**/
 @RestController
+@RequestMapping("/v1")
 public class PostController {
 
     @Autowired

jpa-one-to-many-demo/src/main/java/com/example/jpa/exception/ResourceNotFoundException.java → jpa-one-to-many-demo/src/main/java/com/amit/jpa/exception/ResourceNotFoundException.java

@@ -1,11 +1,20 @@
-package com.example.jpa.exception;
+package com.amit.jpa.exception;
 
 import org.springframework.http.HttpStatus;
 import org.springframework.web.bind.annotation.ResponseStatus;
-
+/**
+*
+* @author Amit Patil
+*
+**/
 @ResponseStatus(HttpStatus.NOT_FOUND)
 public class ResourceNotFoundException extends RuntimeException {
-    public ResourceNotFoundException() {
+    /**
+	 * 
+	 */
+	private static final long serialVersionUID = -6284714764240841538L;
+
+	public ResourceNotFoundException() {
         super();
     }
 

jpa-one-to-many-demo/src/main/java/com/example/jpa/model/AuditModel.java → jpa-one-to-many-demo/src/main/java/com/amit/jpa/model/AuditModel.java

@@ -1,23 +1,37 @@
-package com.example.jpa.model;
+package com.amit.jpa.model;
+
+import java.io.Serializable;
+import java.util.Date;
+
+import javax.persistence.Column;
+import javax.persistence.EntityListeners;
+import javax.persistence.MappedSuperclass;
+import javax.persistence.Temporal;
+import javax.persistence.TemporalType;
 
-import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
 import org.springframework.data.annotation.CreatedDate;
 import org.springframework.data.annotation.LastModifiedDate;
 import org.springframework.data.jpa.domain.support.AuditingEntityListener;
 
-import javax.persistence.*;
-import javax.validation.constraints.NotNull;
-import java.io.Serializable;
-import java.util.Date;
-
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+/**
+*
+* @author Amit Patil
+*
+**/
 @MappedSuperclass
 @EntityListeners(AuditingEntityListener.class)
 @JsonIgnoreProperties(
         value = {"createdAt", "updatedAt"},
         allowGetters = true
 )
 public abstract class AuditModel implements Serializable {
-    @Temporal(TemporalType.TIMESTAMP)
+    /**
+	 * 
+	 */
+	private static final long serialVersionUID = -3515832039273653354L;
+
+	@Temporal(TemporalType.TIMESTAMP)
     @Column(name = "created_at", nullable = false, updatable = false)
     @CreatedDate
     private Date createdAt;