配置绑定

• 简介

# 如何使用Java读取到properties文件中的内容，并且把它封装到JavaBean中
 
public class getProperties {
     public static void main(String[] args) throws FileNotFoundException, IOException {
         Properties pps = new Properties();
         pps.load(new FileInputStream("a.properties"));
         Enumeration enum1 = pps.propertyNames();//得到配置文件的名字
         while(enum1.hasMoreElements()) {
             String strKey = (String) enum1.nextElement();
             String strValue = pps.getProperty(strKey);
             System.out.println(strKey + "=" + strValue);
             //封装到JavaBean。
         }
     }
 }

• 方式1

# 在application外部配置文件中编写配置后
 
# 在实体类中添加如下2个注解
@Component
@ConfigurationProperties(prefix = "mycar")
public class Car {
 
    private String brand;
 
    private Integer price;
 
    public String getBrand() {
        return brand;
    }
 
    public void setBrand(String brand) {
        this.brand = brand;
    }
 
    public Integer getPrice() {
        return price;
    }
 
    public void setPrice(Integer price) {
        this.price = price;
    }
 
    @Override
    public String toString() {
        return "Car{" +
                "brand='" + brand + '\'' +
                ", price=" + price +
                '}';
    }
 
}

• 方式2

# 在application外部配置文件中编写配置后
 
# 在实体类中添加如下注解
@ConfigurationProperties(prefix = "mycar")
public class Car {
 
    private String brand;
 
    private Integer price;
 
    public String getBrand() {
        return brand;
    }
 
    public void setBrand(String brand) {
        this.brand = brand;
    }
 
    public Integer getPrice() {
        return price;
    }
 
    public void setPrice(Integer price) {
        this.price = price;
    }
 
    @Override
    public String toString() {
        return "Car{" +
                "brand='" + brand + '\'' +
                ", price=" + price +
                '}';
    }
 
}
 
# 在配置类中添加如下注解
@EnableConfigurationProperties(Car.class)
//1、开启Car配置绑定功能
//2、把这个Car这个组件自动注册到容器中
public class MyConfig {
}