ApplicationContext——FileSystemXmlApplication(二)

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2、FileSystemXmlApplication：从文件系统中装载配置文件

(1)实现类——Car.java文件

    public class Car {          private String brand;          private String color;          private int maxSpeed;          public Car(){                        }                    public Car(String brand, String color, int maxSpeed) {              super();              this.brand = brand;              this.color = color;              this.maxSpeed = maxSpeed;          }                public String getBrand() {              return brand;          }          public void setBrand(String brand) {              this.brand = brand;          }          public String getColor() {              return color;          }          public void setColor(String color) {              this.color = color;          }          public int getMaxSpeed() {              return maxSpeed;          }          public void setMaxSpeed(int maxSpeed) {              this.maxSpeed = maxSpeed;          }          @Override          public String toString() {              return "brand:"+brand+"  color:"+color+"  maxSpeed:"+maxSpeed;          }      }

(2)配置文件——beans.xml

    <?xml version="1.0" encoding="UTF-8"?>      <beans          xmlns="http://www.springframework.org/schema/beans"          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"          xmlns:p="http://www.springframework.org/schema/p"          xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd">          <bean id="car1" class="com.bean.Car"              p:brand="宝马"              p:color="黑色"              p:maxSpeed="200"/>      </beans>

(3)Spring IoC容器

import org.junit.Test;import org.springframework.context.ApplicationContext;import org.springframework.context.support.FileSystemXmlApplicationContext;/** * @author huamanxi * FileSystemXmlApplicationContext类 */public class FileSystem {@Testpublic void testFileSystem(){ApplicationContext ac=new FileSystemXmlApplicationContext("E://MYeclipse//myeclipse1//ApplicationContext//src//com//bean//beanfactory//beans.xml");System.out.println("init ApplicationContext");Car car=(Car) ac.getBean("car1");System.out.println(car);System.out.println("Car bean is ready for use");}}

运行结果：

init ApplicationContext
brand:宝马 color:黑色 maxSpeed:200
Car bean is ready for use

由运行结果可以看出，两种加载配置文件的方式得到的结果完全相同。

ApplicationContext与BeanFactory初始化的区别：

BeanFactory在初始化容器时，并未实例化Bean，直到第一次访问某个Bean时才实例化目标Bean

而ApplicationContext则在初始化应用上下文时就实例化所有单实例的Bean。

因此ApplicationContext的初始化时间会比BeanFactory稍微长一点。

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