Spring Boot 基础

Spring Boot 基础

Spring Boot 项目（参考1） 提供了一个类似ASP.NET MVC的默认模板一样的标准样板，直接集成了一系列的组件并使用了默认的配置。使用Spring Boot 不会降低学习成本，甚至增加了学习成本，但显著降低了使用成本并提高了开发效率。如果没有Spring基础不建议直接上手。

1.基础项目

这里只关注基于Maven的项目构建，使用Spring Boot CLI命令行工具和Gradle构建方式请参考官网。

（1）创建项目：

创建类型为quickstart的Maven项目，删除默认生成的.java文件保持默认的Maven目录即可。

（2）修改/pom.xml

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 3     xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
 4     <modelVersion>4.0.0</modelVersion>
 5     <groupId>com.example</groupId>
 6     <artifactId>myproject</artifactId>
 7     <version>0.0.1-SNAPSHOT</version>
 8     <properties>
 9         <java.version>1.8</java.version>
10     </properties>
11     <parent>
12         <groupId>org.springframework.boot</groupId>
13         <artifactId>spring-boot-starter-parent</artifactId>
14         <version>1.3.1.RELEASE</version>
15     </parent>
16     <dependencies>
17         <dependency>
18             <groupId>org.springframework.boot</groupId>
19             <artifactId>spring-boot-starter-web</artifactId>
20         </dependency>
21     </dependencies>
22 </project>

（3）添加/src/main/sample/controller/HomeController.java文件：

 1 package simple.controller;
 2
 3 import org.springframework.web.bind.annotation.*;
 4
 5 @RestController
 6 public class HomeController {
 7
 8     @RequestMapping("/")
 9     public String index() {
10         return "Hello World!";
11     }
12 }

（4）添加/src/main/sample/Application.java文件：

 1 package simple;
 2
 3 import org.springframework.boot.*;
 4 import org.springframework.boot.autoconfigure.*;
 5 import simple.controller.*;
 6
 7 @EnableAutoConfiguration
 8 public class Application {
 9
10     public static void main(String[] args) throws Exception {
11         SpringApplication.run(new Object[] { Application.class, HomeController.class }, args);
12     }
13
14 }

在浏览器中输入http://localhost:8080/，即可直接看到"Hello World"运行结果。

2. 添加数据访问支持

（1）修改pom，添加spring-boot-starter-data-jpa和h2依赖:

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 3     xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
 4     <modelVersion>4.0.0</modelVersion>
 5     <groupId>com.example</groupId>
 6     <artifactId>myproject</artifactId>
 7     <version>0.0.1-SNAPSHOT</version>
 8     <properties>
 9         <java.version>1.8</java.version>
10     </properties>
11     <parent>
12         <groupId>org.springframework.boot</groupId>
13         <artifactId>spring-boot-starter-parent</artifactId>
14         <version>1.3.1.RELEASE</version>
15     </parent>
16     <dependencies>
17         <dependency>
18             <groupId>org.springframework.boot</groupId>
19             <artifactId>spring-boot-starter-web</artifactId>
20         </dependency>
21         <dependency>
22             <groupId>org.springframework.boot</groupId>
23             <artifactId>spring-boot-starter-data-jpa</artifactId>
24         </dependency>
25         <dependency>
26             <groupId>com.h2database</groupId>
27             <artifactId>h2</artifactId>
28             <scope>runtime</scope>
29         </dependency>
30     </dependencies>
31 </project>

如果需要在控制台查看生成SQL语句，可以添加/src/main/resources/application.properties

1 spring.h2.console.enabled=true
2 logging.level.org.hibernate.SQL=debug

（2）添加实体

添加User、Role、Category和Post实体。

User:

package simple.domain;

import java.util.*;

import javax.persistence.*;

@Entity
public class User {
@Id
@GeneratedValue
private Long id;

private String userName;

private String password;

private String Email;

@javax.persistence.Version
private Long Version;

@ManyToMany(cascade = CascadeType.ALL)
private List<Role> roles = new ArrayList<Role>();

public Long getId() {
return id;
}

public void setId(Long id) {
this.id = id;
}

public String getUserName() {
return userName;
}

public void setUserName(String userName) {
this.userName = userName;
}

public String getPassword() {
return password;
}

public void setPassword(String password) {
this.password = password;
}

public String getEmail() {
return Email;
}

public void setEmail(String email) {
Email = email;
}

public List<Role> getRoles() {
return roles;
}

public void setRoles(List<Role> roles) {
this.roles = roles;
}

public Long getVersion() {
return Version;
}

public void setVersion(Long version) {
Version = version;
}
}

Role:

package simple.domain;

import java.util.*;

import javax.persistence.*;

@Entity
public class Role {
@Id
@GeneratedValue
private Long id;

private String roleName;

@ManyToMany(cascade = CascadeType.ALL)
private List<User> users = new ArrayList<User>();

public Long getId() {
return id;
}

public void setId(Long id) {
this.id = id;
}

public String getRoleName() {
return roleName;
}

public void setRoleName(String roleName) {
this.roleName = roleName;
}

public List<User> getUsers() {
return users;
}

public void setUsers(List<User> users) {
this.users = users;
}
}

Category:

package simple.domain;

import java.util.*;

import javax.persistence.*;

@Entity
public class Category {
@Id
@GeneratedValue
private Long id;

private String Name;

@OneToMany
private List<Post> posts = new ArrayList<Post>();

public Long getId() {
return id;
}

public void setId(Long id) {
this.id = id;
}

public String getName() {
return Name;
}

public void setName(String name) {
Name = name;
}

public List<Post> getPosts() {
return posts;
}

public void setPosts(List<Post> posts) {
this.posts = posts;
}
}

Post:

package simple.domain;

import java.util.*;

import javax.persistence.*;

@Entity
public class Post {
@Id
@GeneratedValue
private Long id;

private String Name;

private String Html;

private String Text;

private Date CreateAt;

@ManyToOne
private Category category;

public Long getId() {
return id;
}

public void setId(Long id) {
this.id = id;
}

public String getName() {
return Name;
}

public void setName(String name) {
Name = name;
}

public String getHtml() {
return Html;
}

public void setHtml(String html) {
Html = html;
}

public String getText() {
return Text;
}

public void setText(String text) {
Text = text;
}

public Date getCreateAt() {
return CreateAt;
}

public void setCreateAt(Date createAt) {
CreateAt = createAt;
}

public Category getCategory() {
return category;
}

public void setCategory(Category category) {
this.category = category;
}
}

（3）添加资源库

添加UserRepository、RoleRepository、CategoryRepository和PostRepository接口，无需实现。

UserRepository:

1 package simple.repository;
2
3 import org.springframework.data.repository.*;
4
5 import simple.domain.*;
6
7 public interface UserRepository extends CrudRepository<User, Long> {
8
9 }

RoleRepository

1 package simple.repository;
2
3 import org.springframework.data.repository.*;
4
5 import simple.domain.*;
6
7 public interface RoleRepository extends CrudRepository<Role, Long> {
8
9 }

CategoryRepository

1 package simple.repository;
2
3 import org.springframework.data.repository.*;
4
5 import simple.domain.*;
6
7 public interface CategoryRepository extends CrudRepository<Category, Long> {
8
9 }

PostRepository

package simple.repository;

import org.springframework.data.repository.*;

import simple.domain.*;

public interface PostRepository extends CrudRepository<User, Long> {

}

（4）在控制器中注入资源库接口

 1 package simple.controller;
 2
 3 import org.springframework.beans.factory.annotation.*;
 4 import org.springframework.web.bind.annotation.*;
 5
 6 import simple.repository.*;
 7
 8 @RestController
 9 public class HomeController {
10
11     private UserRepository userRepository;
12     private RoleRepository roleRepository;
13     private CategoryRepository categoryRepository;
14     private PostRepository postReppository;
15
16     @Autowired
17     public HomeController(UserRepository userRepository, RoleRepository roleRepository,
18             CategoryRepository categoryRepository, PostRepository postReppository) {
19         this.userRepository = userRepository;
20         this.roleRepository = roleRepository;
21         this.categoryRepository = categoryRepository;
22         this.postReppository = postReppository;
23     }
24
25
26     @RequestMapping("/")
27     public long index() {
28         return userRepository.count();
29     }
30 }

使用事务时在方法上应用注解@Transactional

3.添加验证和授权支持

（1）添加spring-boot-starter-security依赖

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 3     xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
 4     <modelVersion>4.0.0</modelVersion>
 5     <groupId>com.example</groupId>
 6     <artifactId>myproject</artifactId>
 7     <version>0.0.1-SNAPSHOT</version>
 8     <properties>
 9         <java.version>1.8</java.version>
10     </properties>
11     <parent>
12         <groupId>org.springframework.boot</groupId>
13         <artifactId>spring-boot-starter-parent</artifactId>
14         <version>1.3.1.RELEASE</version>
15     </parent>
16     <dependencies>
17         <dependency>
18             <groupId>org.springframework.boot</groupId>
19             <artifactId>spring-boot-starter-web</artifactId>
20         </dependency>
21         <dependency>
22             <groupId>org.springframework.boot</groupId>
23             <artifactId>spring-boot-starter-data-jpa</artifactId>
24         </dependency>
25         <dependency>
26             <groupId>com.h2database</groupId>
27             <artifactId>h2</artifactId>
28             <scope>runtime</scope>
29         </dependency>
30         <dependency>
31             <groupId>org.springframework.boot</groupId>
32             <artifactId>spring-boot-starter-security</artifactId>
33         </dependency>
34     </dependencies>
35 </project>

（2）修改Application.java

 1 package simple;
 2
 3 import org.springframework.boot.*;
 4 import org.springframework.boot.autoconfigure.*;
 5 import org.springframework.context.annotation.Bean;
 6 import org.springframework.security.config.annotation.method.configuration.*;
 7 import org.springframework.security.config.annotation.web.builders.HttpSecurity;
 8 import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
 9 import org.springframework.security.web.authentication.SavedRequestAwareAuthenticationSuccessHandler;
10
11 import simple.controller.*;
12
13 @EnableAutoConfiguration
14 @EnableGlobalMethodSecurity(securedEnabled = true, prePostEnabled = true)
15 public class Application {
16
17     public static void main(String[] args) throws Exception {
18         SpringApplication.run(new Object[] { Application.class, HomeController.class }, args);
19     }
20
21     @Bean
22     public WebSecurityConfigurerAdapter webSecurityConfigurerAdapter() {
23         return new MyWebSecurityConfigurer();
24     }
25
26     public static class MyWebSecurityConfigurer extends WebSecurityConfigurerAdapter {
27         @Override
28         protected void configure(HttpSecurity http) throws Exception {
29             http.csrf().disable();
30             http.authorizeRequests().antMatchers("/account**", "/admin**").authenticated();
31             http.formLogin().usernameParameter("userName").passwordParameter("password").loginPage("/login")
32                     .loginProcessingUrl("/login").successHandler(new SavedRequestAwareAuthenticationSuccessHandler())
33                     .and().logout().logoutUrl("/logout").logoutSuccessUrl("/");
34             http.rememberMe().rememberMeParameter("rememberMe");
35
36         }
37     }
38 }

访问http://localhost:8080/account会自动跳转到login登录页。Spring Security的具体使用前文已有所述。

参考：

（1）https://github.com/spring-projects/spring-boot

（2）http://projects.spring.io/spring-boot/

（3）https://github.com/qibaoguang/Spring-Boot-Reference-Guide/blob/master/SUMMARY.md

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