<分区>
每次我进入我的服务类时，存储库似乎都没有 Autowiring ，因为它一直抛出 NullPointerException。任何人都可以帮助检查我缺少什么吗？
这是我的代码:
DemoApplication.java
package com.example;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.orm.jpa.EntityScan;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.stereotype.Controller;
import org.springframework.transaction.annotation.EnableTransactionManagement;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
@Configuration
@EnableAutoConfiguration
@ComponentScan({"com.example", "com.controller", "com.repositories", "com.service", "com.model"})
@EntityScan(basePackages = {"com.model"})
@EnableJpaRepositories(basePackages = {"com.repositories"})
@EnableTransactionManagement
public class DemoApplication {
public static void main(String[] args) {
SpringApplication.run(DemoApplication.class, args);
}
}
Person.java
package com.model;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
@Entity
public class Person {
@Id
@GeneratedValue(strategy=GenerationType.AUTO)
long id;
String firstName;
String lastName;
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
}
PersonRepository.java
package com.repositories;
import com.model.Person;
import org.springframework.data.repository.CrudRepository;
public interface PersonRepository extends CrudRepository<Person, Long> {
}
个人服务.java
package com.service;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.List;
import com.model.Person;
import com.repositories.PersonRepository;
@Service
public class PersonService {
private PersonRepository pr;
@Autowired
public void setPersonRepository(PersonRepository pr) {
this.pr = pr;
}
public List<Person> listAll() {
return null;
}
public Person getByName(String firstName, String lastName) {
return null;
}
public Person saveOrUpdate(Person p) {
pr.save(p);
return p;
}
}
应用程序属性
spring.datasource.url:jdbc:h2:mem:testdb
spring.datasource.username=sa
spring.datasource.password=
spring.datasource.driverClassName=org.h2.Driver
pom.xml
<?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>
<groupId>com.example</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>demo</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.3.3.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<java.version>1.7</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</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-thymeleaf</artifactId>
</dependency>
<dependency>
<groupId>org.hibernate.javax.persistence</groupId>
<artifactId>hibernate-jpa-2.1-api</artifactId>
<version>1.0.0.Final</version>
</dependency>
<dependency>
<groupId>org.eclipse.persistence</groupId>
<artifactId>javax.persistence</artifactId>
<version>2.0.0</version>
<scope>compile</scope>
</dependency>
<dependency>
<groupId>com.h2database</groupId>
<artifactId>h2</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
PersonController.java
package com.controller;
import javax.servlet.http.HttpServletRequest;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.ui.ModelMap;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.support.SessionStatus;
import com.model.Person;
import com.service.PersonService;
@Controller
public class PersonController {
@RequestMapping("/person")
public String person(Model model) {
PersonService ps = new PersonService();
Person p = ps.getByName("John", "Doe");
model.addAttribute("person", p);
return "personview";
}
@RequestMapping(value = "/", method = RequestMethod.GET)
public String getHomePage() {
return "homeview";
}
@RequestMapping(value = "/add", method = RequestMethod.GET)
public String getRegFormPage(ModelMap model) {
model.addAttribute("person", new Person());
return "addpersonview";
}
@RequestMapping(value="/add", method = RequestMethod.POST)
public String processRegFormPage(ModelMap model, @ModelAttribute("person") Person p, BindingResult result, SessionStatus status, HttpServletRequest request) throws Exception {
PersonService ps = new PersonService();
ps.saveOrUpdate(p);
model.addAttribute("person", p);
return "personview";
}
}