现在使用java的配置
@Configuration ：声明一个类作为配置类，代替 xml 文件 @Bean ：声明在方法上，将方法的返回值加入 Bean 容器，代替1.pom文件
2.application配置文件
3.java配置获取参数
package com.ljf.spring.boot.demo.config;
import com.alibaba.druid.pool.DruidDataSource;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
import javax.sql.DataSource;
@Configuration
@PropertySource("classpath:application.properties")
public class ParamConfig {
@Value("${jdbc.url}")
String url;
@Value("${jdbc.driverClassName}")
String driverClassName;
@Value("${jdbc.username}")
String username;
@Value("${jdbc.password}")
String password;
//第一种方式
@Bean
public DataSource dataSource(){
DruidDataSource dataSource = new DruidDataSource();
dataSource.setDriverClassName(driverClassName);
System.out.println("driverClassName:"+driverClassName);
dataSource.setUrl(url); dataSource.setUsername(username);
dataSource.setPassword(password);
return dataSource;
}
}
@Configuration
：声明我们
JdbcConfig
是一个配置类
@PropertySource
：指定属性文件的路径是
:
classpath:jdbc.properties
通过
@Value
为属性注入值
通过
@Bean
将
dataSource()
方
法声明为一个注册Bean的方法，Spring会自动调用该方法，将方法的返回值 加入Spring容器中。
4.
我们就可以在任意位置通过
@Autowired
注入
DataSource
了！
5.结果
1.2 使用java配置获取参数在Spring Boot中，提供了一种新的属性注入方式，支持各种java基本数据类型及复杂类型的注入。
1.基本类：
package com.ljf.spring.boot.demo.config;
import org.springframework.boot.context.properties.ConfigurationProperties;
@ConfigurationProperties(prefix = "jdbc")
public class JdbcProperties {
private String url;
private String driverClassName;
private String username;
private String password;
public String getUrl() {
return url;
}
public void setUrl(String url) {
this.url = url;
}
public String getDriverClassName() {
return driverClassName;
}
public void setDriverClassName(String driverClassName) {
this.driverClassName = driverClassName;
}
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;
}
}
2.配置获取类
package com.ljf.spring.boot.demo.config;
import com.alibaba.druid.pool.DruidDataSource;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import javax.sql.DataSource;
@Configuration
@EnableConfigurationProperties(JdbcProperties.class)
public class JdbcConfig {
@Autowired
private JdbcProperties prop;
public JdbcConfig(JdbcProperties prop) {
System.out.println("第2种autorwire:"+prop.getDriverClassName());
this.prop = prop;
}
public String getInfo(){
System.out.println("第1种autorwire:"+prop.getDriverClassName());
return "第1种autorwire:"+prop.getDriverClassName();
}
@Bean
public DataSource dataSource(JdbcProperties prop){
DruidDataSource dataSource = new DruidDataSource();
dataSource.setDriverClassName(prop.getDriverClassName());
System.out.println("第3种 初始bean: driverClassName:"+prop.getDriverClassName());
dataSource.setUrl(prop.getUrl()); dataSource.setUsername(prop.getUsername());
dataSource.setPassword(prop.getPassword());
return dataSource;
}
}
4.优化controller类
package com.ljf.spring.boot.demo.controller;
import com.ljf.spring.boot.demo.config.JdbcConfig;
import com.ljf.spring.boot.demo.config.ParamConfig;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import com.ljf.spring.boot.demo.hello.world.config.*;
import org.springframework.web.bind.annotation.ResponseBody;
@Controller
public class UserController {
@Autowired
private ProdcuctConfig pv ;
@Autowired
private ParamConfig paramConfig;
@Autowired
private JdbcConfig jdbcConfig;
@RequestMapping("/testpv")
@ResponseBody
public String test(){
System.out.println("contorller:获取到bean:"+pv.getDeviceRunStateVo());
return "ok";
}
@RequestMapping("/testp")
@ResponseBody
public String testp(){
// System.out.println("contorller:获取到参数:"+paramConfig.dataSource());
System.out.println("contorller:获取到参数:"+jdbcConfig.getInfo());
return "ok";
}
}
5.启动:
6.访问
打印日志：
