新注解说明
@Configuration
- 作用:用于指定当前类是一个spring配置列,可替换xml配置文件,作用和在spring的xml配置文件的:< beans></ beans>是一样的
- 示例代码
java
/**
* spring的配置类
*/
@Configuration//等价于<beans>,当从一个类上加载到该注解时会创建spring容器
public class SpringConfiguration{
}
@ComponentScan
- 作用:
用于指定spring在初始化容器时要扫描的包。作用和在spring的xml配置文件中的< contextLcomponent-scan base-package="com.by"/>是一样的 - 属性:
basePackages:用于指定要扫描的包。和该注解中的value属性作用一样
示例代码:
java
/**
* spring的配置类
*/
@Configuration
@ComponentScan(basePackages = "com.by")//等价于<context:component-scan>
public class SpringConfiguration{
}
@Bean
-
作用:
该注解只能写在方法上,表明使用此方法创建一个对象,并且放入spring容器。作用和在spring的xml配置文件中的:
<bean/>
是一样的。 -
属性:
name:给当前@Bean注解方法创建的对象指定一个名称(即bean的id)。
-
示例代码
javapublic class Dog { private String nam; private Integer age; //set get...... }
java@Bean public Dog dog(){ Dog dog = new Dog(); dog.setNam("二狗"); dog.setAge(18); return dog; }
@PropertySource
-
作用:
用于加载*.properties文件中的配置。作用和在spring的xml配置文件中的:
<context:property-placeholder location="">
是一样的。 -
属性:
value[]:用于指定properties文件位置。如果是在类路径下,需要写上classpath:
-
示例代码
properties#config.properties nam=二狗 age=18
java@PropertySource("classpath:config.properties") public class SpringConfiguration { @Value("${nam}") private String nam; @Value("${age}") private Integer age; @Bean public Dog dog(){ Dog dog = new Dog(); dog.setNam(nam); dog.setAge(age); return dog; } }
@Import
-
作用:
@Import注解是用来导入配置类或者一些需要前置加载的类。作用和在spring的xml配置文件中的:
<import resource=""></import>
是一样. -
属性:
value[]:用于指定其他配置类的字节码。
-
示例代码
java@Configuration @ComponentScan(basePackages = "com.by") @Import({Configuration_Other.class}) public class SpringConfiguration { } @PropertySource("classpath:config.properties") public class Configuration_Other { }
Spring的纯注解配置
JdbcConfig
java
import com.alibaba.druid.pool.DruidDataSource;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.PropertySource;
import javax.sql.DataSource;
@PropertySource("classpath:db.properties")
public class JdbcConfig {
@Value("${jdbc.driver}")
private String driver;
@Value("${jdbc.url}")
private String url;
@Value("${jdbc.username}")
private String userName;
@Value("${jdbc.password}")
private String password;
@Bean("dataSource")
public DataSource getDatasource() {
DruidDataSource ds = new DruidDataSource();
ds.setDriverClassName(driver);
ds.setUrl(url);
ds.setUsername(userName);
ds.setPassword(password);
return ds;
}
}
MybatisConfig
java
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.mapper.MapperScannerConfigurer;
import org.springframework.context.annotation.Bean;
import javax.sql.DataSource;
public class MyBatisConfig {
@Bean
public SqlSessionFactoryBean getSqlSessionFactoryBean(
DataSource dataSource){
SqlSessionFactoryBean ssfb=new SqlSessionFactoryBean();
ssfb.setDataSource(dataSource);
ssfb.setTypeAliasesPackage("com.by.pojo");
return ssfb;
}
@Bean
public MapperScannerConfigurer getMapperScannerConfigurer(){
MapperScannerConfigurer msc=new MapperScannerConfigurer();
msc.setBasePackage("com.by.mapper");
return msc;
}
}
TxConfig
java
import org.springframework.context.annotation.Bean;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import org.springframework.transaction.PlatformTransactionManager;
import javax.sql.DataSource;
public class TxConfig {
@Bean
public PlatformTransactionManager transactionManager(DataSource dataSource){
DataSourceTransactionManager ds = new DataSourceTransactionManager();
ds.setDataSource(dataSource);
return ds;
}
}
SpringConfig
java
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.transaction.annotation.EnableTransactionManagement;
@Configuration
@Import({MyBatisConfig.class, JdbcConfig.class, TxConfig.class})
//等同<context:component-scan base-package="com.by"/>`
@ComponentScan(value = "com.by.service")
//等同于<tx:annotation-driven />,bean的名称默认取transactionManager
@EnableTransactionManagement
public class SpringConfig {
}
SpringMvcConfig
java
import com.by.converter.MyDateConverter;
import com.by.interceptor.LoginInterceptor;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.format.FormatterRegistry;
import org.springframework.web.multipart.commons.CommonsMultipartResolver;
import org.springframework.web.servlet.ViewResolver;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
import org.springframework.web.servlet.view.InternalResourceViewResolver;
@Configuration
//等同于<context:component-scan base-package="com.by.controller>
@ComponentScan("com.by.controller")
//等同于<mvc:annotation-driven></mvc:annotation-driven>
@EnableWebMvc
public class SpringMvcConfig implements WebMvcConfigurer {
@Bean
public ViewResolver viewResolver() {
InternalResourceViewResolver viewResolver = new InternalResourceViewResolver();
viewResolver.setPrefix("/WEB-INF/pages/"); // 设置视图文件所在目录
viewResolver.setSuffix(".jsp"); // 设置视图文件后缀名
return viewResolver;
}
@Bean
public CommonsMultipartResolver multipartResolver(){
CommonsMultipartResolver commonsMultipartResolver=new CommonsMultipartResolver();
return commonsMultipartResolver;
}
@Override
public void addFormatters(FormatterRegistry registry) {
registry.addConverter(new MyDateConverter());
}
@Override
public void addInterceptors(InterceptorRegistry registry) {
registry.addInterceptor(new LoginInterceptor()).addPathPatterns("/emp/**");
}
@Override
public void addResourceHandlers(ResourceHandlerRegistry registry) {
registry.addResourceHandler("/head/**").addResourceLocations("/head/");
}
}
WebConfig
java
import org.springframework.web.filter.CharacterEncodingFilter;
import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;
import javax.servlet.Filter;
/**
* 当类扩展了AbstractAnnotationConfigDispatcherServletlnitializer并将其部署到 Servlet容器时,
* 容器会自动发现它,并用它来配置Servlet环境
*/
public class WebConfig extends AbstractAnnotationConfigDispatcherServletInitializer {
//加载Spring配置类
protected Class<?>[] getRootConfigClasses() {
return new Class[]{SpringConfig.class};
}
//加载SpringMVC配置类
protected Class<?>[] getServletConfigClasses() {
return new Class[]{SpringMvcConfig.class};
}
//设置SpringMVC请求地址拦截规则
protected String[] getServletMappings() {
return new String[]{"/"};
}
//设置post请求中文乱码过滤器
@Override
protected Filter[] getServletFilters() {
CharacterEncodingFilter filter = new CharacterEncodingFilter();
filter.setEncoding("utf-8");
return new Filter[]{filter};
}
}
删除xml配置文件
修改web.xml
xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
version="4.0">
<welcome-file-list>
<welcome-file>login.jsp</welcome-file>
</welcome-file-list>
</web-app>