前文我们使用SPRING INITIALIZR快速构建了一个空的Spring Boot项目，并增加web模块实现了HTTP请求。
这一篇继续在该demo的基础上，增加JPA的功能。
JPA全称Java Persistence API.JPA通过JDK 5.0注解或XML描述对象关系表的映射关系，并将运行时的实体对象持久化到数据库中。
引入JPA模块
1.在POM文件中添加：
<!-- JPA模块 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<!-- mysql -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
2.在application.properties属性文件中定义好数据源（传统做法，这里不演示了）
2.(我们使用Spring推荐的yml来配置)新建application.yml文件，内容如下：
server:
port: 8000
spring:
application:
name: demo
jpa:
properties:
hibernate:
cache:
use_second_level_cache: false
use_query_cache: false
generate_statistics: true
cache.region.factory_class: org.hibernate.cache.ehcache.EhCacheRegionFactory
generate-ddl: false
hibernate:
ddl-auto: update
show-sql: true
datasource:
platform: mysql
url: jdbc:mysql://127.0.0.1:3306/demo?useUnicode=true&characterEncoding=utf8
username: root
password: 你的数据库密码
# schema: classpath:schema.sql
# data: classpath:data.sql
logging:
level:
root: info
相应的，在本地创建一个叫demo的数据库，用于我们的测试。
定义2个实体
1.新建包com.v5ent.demo.domain
2.在这个包下新建两个实体类Tag和Note，代码如下
/*
* 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 com.v5ent.demo.domain; import java.util.List; import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.ManyToMany;
import javax.persistence.SequenceGenerator; @Entity
public class Note { @Id
@SequenceGenerator(name="note_generator", sequenceName="note_sequence", initialValue = 5)
@GeneratedValue(generator = "note_generator")
private long id; private String title; private String body; @ManyToMany
private List<Tag> tags; protected Note() {}; public Note(String title, String body) {
this.title = title;
this.body = body;
} public long getId() {
return this.id;
} public void setId(long id) {
this.id = id;
} public String getTitle() {
return this.title;
} public void setTitle(String title) {
this.title = title;
} public String getBody() {
return this.body;
} public void setBody(String body) {
this.body = body;
} public List<Tag> getTags() {
return this.tags;
} public void setTags(List<Tag> tags) {
this.tags = tags;
} }
Tag：
/*
* 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 com.v5ent.demo.domain; import java.util.List; import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.ManyToMany;
import javax.persistence.SequenceGenerator; @Entity
public class Tag { @Id
@SequenceGenerator(name="tag_generator", sequenceName="tag_sequence", initialValue = 4)
@GeneratedValue(generator = "tag_generator")
private long id; private String name; @ManyToMany(mappedBy = "tags")
private List<Note> notes; public long getId() {
return this.id;
} public void setId(long id) {
this.id = id;
} public String getName() {
return this.name;
} public void setName(String name) {
this.name = name;
} public List<Note> getNotes() {
return this.notes;
} public void setNotes(List<Note> notes) {
this.notes = notes;
} }
这里我们定义了两个多对多的实体，笔记和标签。
定义2个实体的Jpa
1.新建包com.v5ent.demo.repository
2.在这个包下新建两个Jpa类TagRepository和NoteRepository，代码如下
package com.v5ent.demo.repository; import org.springframework.data.jpa.repository.JpaRepository; import com.v5ent.demo.domain.Tag; /**
* Spring Data JPA repository for the Tag entity.
*/
public interface TagRepository extends JpaRepository<Tag,Long> { }
package com.v5ent.demo.repository; import java.util.List; import org.springframework.data.jpa.repository.JpaRepository; import com.v5ent.demo.domain.Note; /**
* Spring Data JPA repository for the Note entity.
*/
public interface NoteRepository extends JpaRepository<Note,Long> { }
至此，所有的工作就完成了。
大家可以看一下仓库类的父类，常用的数据库访问操作都默认实现了。
JPA的查询方法
在JPA中有三种方式可以进行数据的查询（1,方法命名查询 2,@NamedQuery查询 3,@Query查询），
第一种：方法命名查询
1. Spring Data JPA支持通过定义在Repository接口的方法来定义查询，方法名字是根据实体类的属性名来确定的，示例如下：
/**
* Spring Data JPA repository for the Note entity.
*/
public interface NoteRepository extends JpaRepository<Note,Long> { List<Note> findByBody(String body);
List<Note> findByTitleAndBody(String title,String body);
}
从代码可以看出，使用findBy这样的关键字，就可以直接实现根据字段查询。（这里的findBy也可以用find,getBy,query,read代替）而And就相当于sql语句中的and。
2.用关键字限制结果数量，用top和first来实现，示例：
/*
*查询符合条件的前十条记录
*/
List<Note> findFirst10ByTitle(String title)
/*
*查询符合条件的前30条记录
*/
List<Note> findTop30ByTitle(String title);
第二种：@NamedQuery查询
Spring Data JPA 支持@NameQuery来定义查询方法，即一个名称映射一个查询语句(要在实体类上写，不是接口里写)，示例如下：
@Entity
@NamedQuery(name="Note.findByTitle",
query="select p from Note p where p.title=?1")
public class Note{ }
如果要将多个方法都进行重新定义，可以使用@NameQueries标签,示例如下：
@Entity
@NamedQueries({
@NamedQuery(name="Note.findByTitle",
query="select p from Note p where p.title=?1"),
@NamedQuery(name = "Note.withTitleAndBodyQuery",
query = "select p from Note p where p.title=?1 and body=?2")
})
public class Note{ }
这个时候，接口里定义的findByName方法就是上面的方法了，不再是方法命名查询的方法了。
第三种：@Query查询
Spring Data JPA 支持@Query来定义查询方法，使用方法是将@Query写在接口的方法上面，示例如下：
public interface NoteRepository extends JpaRepository<Note, Long> {
@Query("select p from Note p where p.title like ?1 ")
List<Note> anyQuery(String title);
}
这里的参数是根据索引号来进行查询的。
当然我们也是可以根据名称来进行匹配，然后进行查询的，示例如下：
public interface NoteRepository extends JpaRepository<Note, Long> {
@Query("select p from Note p where p.title like :title")
List<Note> anyQuery(@Param("title")String title); }
如果是模糊匹配呢，这么写：
@Query("select p from Note p where p.title like %:title%")
List<Note> anyQuery(@Param("title")String title);
我们再来看看更新是如何写的。
Spring Data JPA支持使用@Modifying和@Query注解组合来进行更新查询，示例如下：
@Modifying
@Transcational
@Query("update Note p set p.title=?1 ")
int setTitle(String title);
int表示的是更新语句所影响的行数。
来测试看看
1.我们不准使用之前的测试类，我准备直接在启动的时候测试。首先在DemoApplication中增加如下测试代码：
@Bean
public CommandLineRunner demo(final NoteRepository repository) {
return new CommandLineRunner() { @Override
public void run(String... args) throws Exception {
// save a couple of Notes
repository.save(new Note("Have a nice Day", "Don’t let mental blocks control you. Set yourself free. Confront your fear and turn the mental blocks into building blocks."));
repository.save(new Note("x-Notes", "Chloe O'Brian,Kim Bauer"));
repository.save(new Note("Some Others", "No news is good news")); // fetch all Notes
log.info("Notes found with findAll():");
log.info("-------------------------------");
for (Note note : repository.findAll()) {
log.info(note.toString());
} // fetch an individual note by ID
Note note = repository.findOne(1L);
log.info("Note found with findOne(1L):");
log.info("--------------------------------");
log.info(note.toString()); // fetch Notes by last name
log.info("Note found with anyQuery(\"Some\"):");
log.info("--------------------------------------------");
for (Note bauer : repository.anyQuery("Some")) {
log.info(bauer.toString());
}
}
};
}
2.执行main方法跑起来，我们可以看到控制台输出了我们的操作日志。
-- ::07.820 INFO --- [ main] com.v5ent.demo.DemoApplication : Note found with findOne(1L):
-- ::07.820 INFO --- [ main] com.v5ent.demo.DemoApplication : --------------------------------
-- ::07.820 INFO --- [ main] com.v5ent.demo.DemoApplication : com.v5ent.demo.domain.Note@7893c715
-- ::07.820 INFO --- [ main] com.v5ent.demo.DemoApplication : Note found with anyQuery("Some"):
-- ::07.820 INFO --- [ main] com.v5ent.demo.DemoApplication : --------------------------------------------
补充
不得不提，在此基础上，实现Rest化API很简单。下面来展开实验：
在当前的情况下，我们看一下mvc方面的日志：
-- ::45.980 INFO --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/hello]}" onto public java.lang.String com.v5ent.demo.web.HelloController.index()
-- ::45.985 INFO --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error]}" onto public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String, java.lang.Object>> org.springframework.boot.autoconfigure.web.BasicErrorController.error(javax.servlet.http.HttpServletRequest)
-- ::45.985 INFO --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],produces=[text/html]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse)
-- ::46.024 INFO --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-05-18 12:13:46.024 INFO 12664 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-05-18 12:13:46.078 INFO 12664 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
-- ::46.354 INFO --- [ main] o.s.j.e.a.AnnotationMBeanExporter : Registering beans for JMX exposure on startup
-- ::46.421 INFO --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): (http)
可以看到/hello这个我们之前实现的controller，如果我们要实现note和tag的对外api，当然也要自己写controller。但是Sring就是专门把这些固定的做法实现的机构，所以Spring已经封装了rest风格api所需要的controller实现。
简单来讲，我们只需要在pom文件中增加：
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-rest</artifactId>
</dependency>
ok，现在启动看看日志：
-- ::36.876 INFO --- [ main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@72a7c7e0: startup date [Thu May :: CST ]; root of context hierarchy
-- ::36.954 INFO --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/hello]}" onto public java.lang.String com.v5ent.demo.web.HelloController.index()
-- ::36.958 INFO --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error]}" onto public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String, java.lang.Object>> org.springframework.boot.autoconfigure.web.BasicErrorController.error(javax.servlet.http.HttpServletRequest)
-- ::36.959 INFO --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],produces=[text/html]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse)
-- ::36.994 INFO --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-05-18 12:55:36.995 INFO 7124 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-05-18 12:55:37.010 INFO 7124 --- [ main] .m.m.a.ExceptionHandlerExceptionResolver : Detected @ExceptionHandler methods in repositoryRestExceptionHandler
2017-05-18 12:55:37.102 INFO 7124 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
-- ::37.262 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@72a7c7e0: startup date [Thu May :: CST ]; root of context hierarchy
-- ::37.275 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/ || ],methods=[OPTIONS],produces=[application/hal+json || application/json]}" onto public org.springframework.http.HttpEntity<?> org.springframework.data.rest.webmvc.RepositoryController.optionsForRepositories()
-- ::37.276 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/ || ],methods=[HEAD],produces=[application/hal+json || application/json]}" onto public org.springframework.http.ResponseEntity<?> org.springframework.data.rest.webmvc.RepositoryController.headForRepositories()
-- ::37.277 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/ || ],methods=[GET],produces=[application/hal+json || application/json]}" onto public org.springframework.http.HttpEntity<org.springframework.data.rest.webmvc.RepositoryLinksResource> org.springframework.data.rest.webmvc.RepositoryController.listRepositories()
-- ::37.280 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}/{id}],methods=[DELETE],produces=[application/hal+json || application/json]}" onto public org.springframework.http.ResponseEntity<?> org.springframework.data.rest.webmvc.RepositoryEntityController.deleteItemResource(org.springframework.data.rest.webmvc.RootResourceInformation,java.io.Serializable,org.springframework.data.rest.webmvc.support.ETag) throws org.springframework.data.rest.webmvc.ResourceNotFoundException,org.springframework.web.HttpRequestMethodNotSupportedException
-- ::37.280 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}/{id}],methods=[PATCH],produces=[application/hal+json || application/json]}" onto public org.springframework.http.ResponseEntity<org.springframework.hateoas.ResourceSupport> org.springframework.data.rest.webmvc.RepositoryEntityController.patchItemResource(org.springframework.data.rest.webmvc.RootResourceInformation,org.springframework.data.rest.webmvc.PersistentEntityResource,java.io.Serializable,org.springframework.data.rest.webmvc.PersistentEntityResourceAssembler,org.springframework.data.rest.webmvc.support.ETag,java.lang.String) throws org.springframework.web.HttpRequestMethodNotSupportedException,org.springframework.data.rest.webmvc.ResourceNotFoundException
-- ::37.280 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}],methods=[OPTIONS],produces=[application/hal+json || application/json]}" onto public org.springframework.http.ResponseEntity<?> org.springframework.data.rest.webmvc.RepositoryEntityController.optionsForCollectionResource(org.springframework.data.rest.webmvc.RootResourceInformation)
-- ::37.281 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}],methods=[HEAD],produces=[application/hal+json || application/json]}" onto public org.springframework.http.ResponseEntity<?> org.springframework.data.rest.webmvc.RepositoryEntityController.headCollectionResource(org.springframework.data.rest.webmvc.RootResourceInformation,org.springframework.data.rest.webmvc.support.DefaultedPageable) throws org.springframework.web.HttpRequestMethodNotSupportedException
-- ::37.281 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}],methods=[GET],produces=[application/hal+json || application/json]}" onto public org.springframework.hateoas.Resources<?> org.springframework.data.rest.webmvc.RepositoryEntityController.getCollectionResource(org.springframework.data.rest.webmvc.RootResourceInformation,org.springframework.data.rest.webmvc.support.DefaultedPageable,org.springframework.data.domain.Sort,org.springframework.data.rest.webmvc.PersistentEntityResourceAssembler) throws org.springframework.data.rest.webmvc.ResourceNotFoundException,org.springframework.web.HttpRequestMethodNotSupportedException
-- ::37.281 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}],methods=[GET],produces=[application/x-spring-data-compact+json || text/uri-list]}" onto public org.springframework.hateoas.Resources<?> org.springframework.data.rest.webmvc.RepositoryEntityController.getCollectionResourceCompact(org.springframework.data.rest.webmvc.RootResourceInformation,org.springframework.data.rest.webmvc.support.DefaultedPageable,org.springframework.data.domain.Sort,org.springframework.data.rest.webmvc.PersistentEntityResourceAssembler) throws org.springframework.data.rest.webmvc.ResourceNotFoundException,org.springframework.web.HttpRequestMethodNotSupportedException
-- ::37.281 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}],methods=[POST],produces=[application/hal+json || application/json]}" onto public org.springframework.http.ResponseEntity<org.springframework.hateoas.ResourceSupport> org.springframework.data.rest.webmvc.RepositoryEntityController.postCollectionResource(org.springframework.data.rest.webmvc.RootResourceInformation,org.springframework.data.rest.webmvc.PersistentEntityResource,org.springframework.data.rest.webmvc.PersistentEntityResourceAssembler,java.lang.String) throws org.springframework.web.HttpRequestMethodNotSupportedException
-- ::37.282 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}/{id}],methods=[OPTIONS],produces=[application/hal+json || application/json]}" onto public org.springframework.http.ResponseEntity<?> org.springframework.data.rest.webmvc.RepositoryEntityController.optionsForItemResource(org.springframework.data.rest.webmvc.RootResourceInformation)
-- ::37.282 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}/{id}],methods=[HEAD],produces=[application/hal+json || application/json]}" onto public org.springframework.http.ResponseEntity<?> org.springframework.data.rest.webmvc.RepositoryEntityController.headForItemResource(org.springframework.data.rest.webmvc.RootResourceInformation,java.io.Serializable,org.springframework.data.rest.webmvc.PersistentEntityResourceAssembler) throws org.springframework.web.HttpRequestMethodNotSupportedException
-- ::37.282 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}/{id}],methods=[GET],produces=[application/hal+json || application/json]}" onto public org.springframework.http.ResponseEntity<org.springframework.hateoas.Resource<?>> org.springframework.data.rest.webmvc.RepositoryEntityController.getItemResource(org.springframework.data.rest.webmvc.RootResourceInformation,java.io.Serializable,org.springframework.data.rest.webmvc.PersistentEntityResourceAssembler,org.springframework.http.HttpHeaders) throws org.springframework.web.HttpRequestMethodNotSupportedException
-- ::37.283 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}/{id}],methods=[PUT],produces=[application/hal+json || application/json]}" onto public org.springframework.http.ResponseEntity<? extends org.springframework.hateoas.ResourceSupport> org.springframework.data.rest.webmvc.RepositoryEntityController.putItemResource(org.springframework.data.rest.webmvc.RootResourceInformation,org.springframework.data.rest.webmvc.PersistentEntityResource,java.io.Serializable,org.springframework.data.rest.webmvc.PersistentEntityResourceAssembler,org.springframework.data.rest.webmvc.support.ETag,java.lang.String) throws org.springframework.web.HttpRequestMethodNotSupportedException
-- ::37.285 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}/{id}/{property}],methods=[DELETE],produces=[application/hal+json || application/json]}" onto public org.springframework.http.ResponseEntity<? extends org.springframework.hateoas.ResourceSupport> org.springframework.data.rest.webmvc.RepositoryPropertyReferenceController.deletePropertyReference(org.springframework.data.rest.webmvc.RootResourceInformation,java.io.Serializable,java.lang.String) throws java.lang.Exception
-- ::37.286 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}/{id}/{property}],methods=[GET],produces=[application/x-spring-data-compact+json || text/uri-list]}" onto public org.springframework.http.ResponseEntity<org.springframework.hateoas.ResourceSupport> org.springframework.data.rest.webmvc.RepositoryPropertyReferenceController.followPropertyReferenceCompact(org.springframework.data.rest.webmvc.RootResourceInformation,java.io.Serializable,java.lang.String,org.springframework.data.rest.webmvc.PersistentEntityResourceAssembler) throws java.lang.Exception
-- ::37.286 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}/{id}/{property}],methods=[GET],produces=[application/hal+json || application/json]}" onto public org.springframework.http.ResponseEntity<org.springframework.hateoas.ResourceSupport> org.springframework.data.rest.webmvc.RepositoryPropertyReferenceController.followPropertyReference(org.springframework.data.rest.webmvc.RootResourceInformation,java.io.Serializable,java.lang.String,org.springframework.data.rest.webmvc.PersistentEntityResourceAssembler) throws java.lang.Exception
-- ::37.286 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}/{id}/{property}/{propertyId}],methods=[GET],produces=[application/hal+json || application/json]}" onto public org.springframework.http.ResponseEntity<org.springframework.hateoas.ResourceSupport> org.springframework.data.rest.webmvc.RepositoryPropertyReferenceController.followPropertyReference(org.springframework.data.rest.webmvc.RootResourceInformation,java.io.Serializable,java.lang.String,java.lang.String,org.springframework.data.rest.webmvc.PersistentEntityResourceAssembler) throws java.lang.Exception
-- ::37.286 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}/{id}/{property}/{propertyId}],methods=[DELETE],produces=[application/hal+json || application/json]}" onto public org.springframework.http.ResponseEntity<org.springframework.hateoas.ResourceSupport> org.springframework.data.rest.webmvc.RepositoryPropertyReferenceController.deletePropertyReferenceId(org.springframework.data.rest.webmvc.RootResourceInformation,java.io.Serializable,java.lang.String,java.lang.String) throws java.lang.Exception
-- ::37.287 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}/{id}/{property}],methods=[PATCH || PUT || POST],consumes=[application/json || application/x-spring-data-compact+json || text/uri-list],produces=[application/hal+json || application/json]}" onto public org.springframework.http.ResponseEntity<? extends org.springframework.hateoas.ResourceSupport> org.springframework.data.rest.webmvc.RepositoryPropertyReferenceController.createPropertyReference(org.springframework.data.rest.webmvc.RootResourceInformation,org.springframework.http.HttpMethod,org.springframework.hateoas.Resources<java.lang.Object>,java.io.Serializable,java.lang.String) throws java.lang.Exception
-- ::37.288 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}/search],methods=[GET],produces=[application/hal+json || application/json]}" onto public org.springframework.data.rest.webmvc.RepositorySearchesResource org.springframework.data.rest.webmvc.RepositorySearchController.listSearches(org.springframework.data.rest.webmvc.RootResourceInformation)
-- ::37.288 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}/search/{search}],methods=[HEAD],produces=[application/hal+json || application/json]}" onto public org.springframework.http.ResponseEntity<java.lang.Object> org.springframework.data.rest.webmvc.RepositorySearchController.headForSearch(org.springframework.data.rest.webmvc.RootResourceInformation,java.lang.String)
-- ::37.289 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}/search/{search}],methods=[GET],produces=[application/hal+json || application/json]}" onto public org.springframework.http.ResponseEntity<?> org.springframework.data.rest.webmvc.RepositorySearchController.executeSearch(org.springframework.data.rest.webmvc.RootResourceInformation,org.springframework.util.MultiValueMap<java.lang.String, java.lang.Object>,java.lang.String,org.springframework.data.rest.webmvc.support.DefaultedPageable,org.springframework.data.domain.Sort,org.springframework.data.rest.webmvc.PersistentEntityResourceAssembler,org.springframework.http.HttpHeaders)
-- ::37.289 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}/search],methods=[HEAD],produces=[application/hal+json || application/json]}" onto public org.springframework.http.HttpEntity<?> org.springframework.data.rest.webmvc.RepositorySearchController.headForSearches(org.springframework.data.rest.webmvc.RootResourceInformation)
-- ::37.290 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}/search/{search}],methods=[OPTIONS],produces=[application/hal+json || application/json]}" onto public org.springframework.http.ResponseEntity<java.lang.Object> org.springframework.data.rest.webmvc.RepositorySearchController.optionsForSearch(org.springframework.data.rest.webmvc.RootResourceInformation,java.lang.String)
-- ::37.291 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}/search/{search}],methods=[GET],produces=[application/x-spring-data-compact+json]}" onto public org.springframework.hateoas.ResourceSupport org.springframework.data.rest.webmvc.RepositorySearchController.executeSearchCompact(org.springframework.data.rest.webmvc.RootResourceInformation,org.springframework.http.HttpHeaders,org.springframework.util.MultiValueMap<java.lang.String, java.lang.Object>,java.lang.String,java.lang.String,org.springframework.data.rest.webmvc.support.DefaultedPageable,org.springframework.data.domain.Sort,org.springframework.data.rest.webmvc.PersistentEntityResourceAssembler)
-- ::37.291 INFO --- [ main] o.s.d.r.w.RepositoryRestHandlerMapping : Mapped "{[/{repository}/search],methods=[OPTIONS],produces=[application/hal+json || application/json]}" onto public org.springframework.http.HttpEntity<?> org.springframework.data.rest.webmvc.RepositorySearchController.optionsForSearches(org.springframework.data.rest.webmvc.RootResourceInformation)
-- ::37.294 INFO --- [ main] o.s.d.r.w.BasePathAwareHandlerMapping : Mapped "{[/profile],methods=[GET]}" onto org.springframework.http.HttpEntity<org.springframework.hateoas.ResourceSupport> org.springframework.data.rest.webmvc.ProfileController.listAllFormsOfMetadata()
-- ::37.295 INFO --- [ main] o.s.d.r.w.BasePathAwareHandlerMapping : Mapped "{[/profile],methods=[OPTIONS]}" onto public org.springframework.http.HttpEntity<?> org.springframework.data.rest.webmvc.ProfileController.profileOptions()
-- ::37.295 INFO --- [ main] o.s.d.r.w.BasePathAwareHandlerMapping : Mapped "{[/profile/{repository}],methods=[GET],produces=[application/alps+json || */*]}" onto org.springframework.http.HttpEntity<org.springframework.data.rest.webmvc.RootResourceInformation> org.springframework.data.rest.webmvc.alps.AlpsController.descriptor(org.springframework.data.rest.webmvc.RootResourceInformation)
-- ::37.295 INFO --- [ main] o.s.d.r.w.BasePathAwareHandlerMapping : Mapped "{[/profile/{repository}],methods=[OPTIONS],produces=[application/alps+json]}" onto org.springframework.http.HttpEntity<?> org.springframework.data.rest.webmvc.alps.AlpsController.alpsOptions()
-- ::37.296 INFO --- [ main] o.s.d.r.w.BasePathAwareHandlerMapping : Mapped "{[/profile/{repository}],methods=[GET],produces=[application/schema+json]}" onto public org.springframework.http.HttpEntity<org.springframework.data.rest.webmvc.json.JsonSchema> org.springframework.data.rest.webmvc.RepositorySchemaController.schema(org.springframework.data.rest.webmvc.RootResourceInformation)
-- ::37.465 INFO --- [ main] o.s.j.e.a.AnnotationMBeanExporter : Registering beans for JMX exposure on startup
-- ::37.602 INFO --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): (http)
发现多了很多rest api的映射，这表示成功了。
访问http://localhost:8000/notes/1，可以看到rest api已经直接可用了。hal+json 的格式，如果有疑问可留言。