I am using Spring Boot to create a courses and Topics database. I am having trouble with a bunch of errors that showed up once I made changes to my Courses classes. I am not sure what's wrong. Here are the error messages:
ERROR 1136 --- [ main] org.hibernate.tool.hbm2ddl.SchemaExport : HHH000389: Unsuccessful: alter table course drop constraint FKokaxyfpv8p583w8yspapfb2ar
ERROR 1136 --- [ main] org.hibernate.tool.hbm2ddl.SchemaExport : Schema 'SA' does not exist
ERROR 1136 --- [ main] org.hibernate.tool.hbm2ddl.SchemaExport : HHH000389: Unsuccessful: drop table course
ERROR 1136 --- [ main] org.hibernate.tool.hbm2ddl.SchemaExport : Schema 'SA' does not exist
ERROR 1136 --- [ main] org.hibernate.tool.hbm2ddl.SchemaExport : HHH000389: Unsuccessful: drop table topic
ERROR 1136 --- [ main] org.hibernate.tool.hbm2ddl.SchemaExport : Schema 'SA' does not exist
WARN 1136 --- [ main] o.h.engine.jdbc.spi.SqlExceptionHelper : SQL Warning Code: 10000, SQLState: 01J01
WARN 1136 --- [ main] o.h.engine.jdbc.spi.SqlExceptionHelper :
Database 'memory:testdb' not created, connection made to existing database instead.
Also, here is my Course code, the topics code is alright I think but I am having trouble with this. I am using an internal database.
package ...
@Entity
public class Course {
// here generate constructors and getters/setters
@Id
private String id;
private String Name;
private String description;
@ManyToOne
private Topic topic; //use it to tie this class to the Topic class, to make it easier for the user
public Topic getTopic() {
return topic;
}
public void setTopic(Topic topic) {
this.topic = topic;
}
public Course() {
}
public Course(String id, String name, String description, String topicId) {
super();
this.id = id;
Name = name;
this.description = description;
this.topic = new Topic(topicId,"","");
}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return Name;
}
public void setName(String name) {
Name = name;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
}
Also my Controller:
@RestController() //makes anything a rest controller, every time you build a class and add this on top of it
public class CourseController {
@Autowired // it marks the courseService as something that needs dependency inj.
private CourseService courseService;// To create a service you need a private courseService variable
//GETALL
@RequestMapping("/topics/{id}/courses")
public List<Course> getAllcourses(@PathVariable String id){
return courseService.getAllCourses(id); //getAllCourses for the topic ID
}
//GET
@RequestMapping("/topics/{topicId}/courses/{id}")
public Course getCourse(@PathVariable String id) {
return courseService.getCourse(id);
}
//POST
@RequestMapping(method = RequestMethod.POST, value = "/topics/{topicId}/courses")
public void addCourse(@RequestBody Course course, @PathVariable String topicId) {
course.setTopic(new Topic(topicId, "", ""));
courseService.addCourse(course);
}
//PUT
@RequestMapping(method = RequestMethod.PUT, value = "/topics/{topicId}/courses/{id}")
public void updateCourse(@RequestBody Course course, @PathVariable String id, @PathVariable String topicId) {
course.setTopic(new Topic(topicId, "", ""));
courseService.updateCourse(course);
}
//DELETE
@RequestMapping(method = RequestMethod.DELETE, value = "/topics/{topicId}/courses/{id}")
public void deletecourse(@PathVariable String id, @PathVariable String topicId) {
courseService.deleteCourse(id);
}
}
And finally my Service class:
package io.msela.springbootstarter.course;
import java.util.ArrayList;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
@Service
public class CourseService {
@Autowired // it injects the courseRepository as it's initialized
private CourseRepository courseRepository;
public List<Course> getAllCourses(String topicId){ //getting all is not good!
List<Course> courses = new ArrayList<>() ;
courseRepository.findByTopicId(topicId).forEach(courses::add);
return courses;
}
public Course getCourse(String id) {
return courseRepository.findOne(id);
}
public void addCourse(Course course) {
courseRepository.save(course); //save a course to the database
}
public void updateCourse(Course course) {
courseRepository.save(course);
//save does both add and update
}
public void deleteCourse(String id) {
courseRepository.delete(id);
}
}
EDIT: Here's my pom.xml file as well
http://maven.apache.org/xsd/maven-4.0.0.xsd"> 4.0.0
<groupId>io.msela</groupId>
<artifactId>course-api-data</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>course-api-data</name>
<description>Course API with Spring Data</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.4.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.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-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.apache.derby</groupId>
<artifactId>derby</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
EDIT 2
The Actual error seems to be the following:
Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'courseController': Unsatisfied dependency expressed through field 'courseService'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'courseService': Unsatisfied dependency expressed through field 'courseRepository'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'courseRepository': Invocation of init method failed; nested exception is java.lang.IllegalArgumentException: Could not create query metamodel for method public abstract java.util.List io.msela.springbootstarter.course.CourseRepository.findByName(java.lang.String)!
This error appears in Derby only. It is because your Properties default is set to:
spring.jpa.hibernate.ddl-auto=create-drop
You have to set it to:
spring.jpa.hibernate.ddl-auto=update
Any further information can be found here: https://github.com/spring-projects/spring-boot/issues/7706