Java Web系列：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:

  1 package simple.domain;   2    3 import java.util.*;   4    5 import javax.persistence.*;   6    7 @Entity   8 public class User {   9     @Id  10     @GeneratedValue  11     private Long id;  12   13     private String userName;  14   15     private String password;  16   17     private String Email;  18   19     @javax.persistence.Version  20     private Long Version;  21   22     @ManyToMany(cascade = CascadeType.ALL)  23     private List<Role> roles = new ArrayList<Role>();  24   25     public Long getId() {  26         return id;  27     }  28   29     public void setId(Long id) {  30         this.id = id;  31     }  32   33     public String getUserName() {  34         return userName;  35     }  36   37     public void setUserName(String userName) {  38         this.userName = userName;  39     }  40   41     public String getPassword() {  42         return password;  43     }  44   45     public void setPassword(String password) {  46         this.password = password;  47     }  48   49     public String getEmail() {  50         return Email;  51     }  52   53     public void setEmail(String email) {  54         Email = email;  55     }  56   57     public List<Role> getRoles() {  58         return roles;  59     }  60   61     public void setRoles(List<Role> roles) {  62         this.roles = roles;  63     }  64   65     public Long getVersion() {  66         return Version;  67     }  68   69     public void setVersion(Long version) {  70         Version = version;  71     }  72 }    View Code

Role:

  1 package simple.domain;   2    3 import java.util.*;   4    5 import javax.persistence.*;   6    7 @Entity   8 public class Role {   9     @Id  10     @GeneratedValue  11     private Long id;  12   13     private String roleName;  14   15     @ManyToMany(cascade = CascadeType.ALL)  16     private List<User> users = new ArrayList<User>();  17   18     public Long getId() {  19         return id;  20     }  21   22     public void setId(Long id) {  23         this.id = id;  24     }  25   26     public String getRoleName() {  27         return roleName;  28     }  29   30     public void setRoleName(String roleName) {  31         this.roleName = roleName;  32     }  33   34     public List<User> getUsers() {  35         return users;  36     }  37   38     public void setUsers(List<User> users) {  39         this.users = users;  40     }  41 }    View Code

Category:

  1 package simple.domain;   2    3 import java.util.*;   4    5 import javax.persistence.*;   6    7 @Entity   8 public class Category {   9     @Id  10     @GeneratedValue  11     private Long id;  12   13     private String Name;  14   15     @OneToMany  16     private List<Post> posts = new ArrayList<Post>();  17   18     public Long getId() {  19         return id;  20     }  21   22     public void setId(Long id) {  23         this.id = id;  24     }  25   26     public String getName() {  27         return Name;  28     }  29   30     public void setName(String name) {  31         Name = name;  32     }  33   34     public List<Post> getPosts() {  35         return posts;  36     }  37   38     public void setPosts(List<Post> posts) {  39         this.posts = posts;  40     }  41 }    View Code

Post:

  1 package simple.domain;   2    3 import java.util.*;   4    5 import javax.persistence.*;   6    7 @Entity   8 public class Post {   9     @Id  10     @GeneratedValue  11     private Long id;  12   13     private String Name;  14   15     private String Html;  16   17     private String Text;  18   19     private Date CreateAt;  20   21     @ManyToOne  22     private Category category;  23   24     public Long getId() {  25         return id;  26     }  27   28     public void setId(Long id) {  29         this.id = id;  30     }  31   32     public String getName() {  33         return Name;  34     }  35   36     public void setName(String name) {  37         Name = name;  38     }  39   40     public String getHtml() {  41         return Html;  42     }  43   44     public void setHtml(String html) {  45         Html = html;  46     }  47   48     public String getText() {  49         return Text;  50     }  51   52     public void setText(String text) {  53         Text = text;  54     }  55   56     public Date getCreateAt() {  57         return CreateAt;  58     }  59   60     public void setCreateAt(Date createAt) {  61         CreateAt = createAt;  62     }  63   64     public Category getCategory() {  65         return category;  66     }  67   68     public void setCategory(Category category) {  69         this.category = category;  70     }  71 }    View Code

（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。