Java中spring读取配置文件的几种方法示例

package springdemo;public class HelloBean {  private String helloWorld;  public String getHelloWorld() {    return helloWorld;  }  public void setHelloWorld(String helloWorld) {    this.helloWorld = helloWorld;  }}

<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd" ><beans>　　<bean id="helloBean" class="springdemo.HelloBean">　　　　<property name="helloWorld">　　　　　　<value>Hello!chb!</value>　　　　</property>　　</bean></beans>

ApplicationContext context = new ClassPathXmlApplicationContext("bean_config.xml");//这种用法不够灵活，不建议使用。 HelloBean helloBean = (HelloBean)context.getBean("helloBean"); System.out.println(helloBean.getHelloWorld());

public interface BeanFactory {  public Object getBean(String id);}//实现类ClassPathXmlApplicationContextimport java.lang.reflect.Method;import java.util.HashMap;import java.util.List;import java.util.Map;import org.jdom.Document;import org.jdom.Element;import org.jdom.input.SAXBuilder;public class ClassPathXmlApplicationContext implements BeanFactory {    private Map<String , Object> beans = new HashMap<String, Object>();    //(IOC:Inverse of Control/DI:Dependency Injection)  public ClassPathXmlApplicationContext() throws Exception {    SAXBuilder sb=new SAXBuilder();        Document doc=sb.build(this.getClass().getClassLoader().getResourceAsStream("beans.xml")); //构造文档对象    Element root=doc.getRootElement(); //获取根元素HD    List list=root.getChildren("bean");//取名字为disk的所有元素    for(int i=0;i<list.size();i++){      Element element=(Element)list.get(i);      String id=element.getAttributeValue("id");      String clazz=element.getAttributeValue("class");      Object o = Class.forName(clazz).newInstance();      System.out.println(id);      System.out.println(clazz);      beans.put(id, o);            for(Element propertyElement : (List<Element>)element.getChildren("property")) {        String name = propertyElement.getAttributeValue("name"); //userDAO        String bean = propertyElement.getAttributeValue("bean"); //u        Object beanObject = beans.get(bean);//UserDAOImpl instance                String methodName = "set" + name.substring(0, 1).toUpperCase() + name.substring(1);        System.out.println("method name = " + methodName);                Method m = o.getClass().getMethod(methodName, beanObject.getClass().getInterfaces()[0]);        m.invoke(o, beanObject);      }         }      }  public Object getBean(String id) {    return beans.get(id);  }}

ApplicationContext context = new ClassPathXmlApplicationContext("bean_config.xml");HelloBean helloBean = (HelloBean)context.getBean("helloBean");BeanFactory factory= new ClassPathXmlApplicationContext("bean_config.xml");HelloBean helloBean = (HelloBean)factory.getBean("helloBean");

Resource rs = new FileSystemResource("D:/software/tomcat/webapps/springWebDemo/WEB-INF/classes/bean_config.xml");BeanFactory factory = new XmlBeanFactory(rs);HelloBean helloBean = (HelloBean)factory.getBean("helloBean");System.out.println(helloBean.getHelloWorld());

helloBean.class=springdemo.HelloBeanhelloBean.helloWorld=Hello!HelloWorld!

BeanDefinitionRegistry reg = new DefaultListableBeanFactory();PropertiesBeanDefinitionReader reader = new PropertiesBeanDefinitionReader(reg);reader.loadBeanDefinitions(new ClassPathResource("bean_config.properties"));BeanFactory factory = (BeanFactory)reg;HelloBean helloBean = (HelloBean)factory.getBean("helloBean");System.out.println(helloBean.getHelloWorld());

InputStream inputStream = this.getClass().getClassLoader().getResourceAsStream("ip_config.properties");Properties p = new Properties();try {  p.load(inputStream);} catch (IOException e1) {  e1.printStackTrace();}System.out.println("ip:"+p.getProperty("ip")+",port:"+p.getProperty("port"));

private WebApplicationContext wac;wac =WebApplicationContextUtils.getRequiredWebApplicationContext(this.getServletContext());wac = WebApplicationContextUtils.getWebApplicationContext(this.getServletContext());JdbcTemplate jdbcTemplate = (JdbcTemplate)ctx.getBean("jdbcTemplate");