Spring接口学习

1.ApplicationContextAware的使用
实现ApplicationContextAware接口，实现setApplicationContext方法，就可以在程序中获取bean的一些基本信息。
1.1 实现ApplicationContextAware接口的工具类定义

package com.test.utils;

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;

/**
 * Created by yangjianzhou on 7/2/15.
 */
@Component
public class SpringContextUtil implements ApplicationContextAware {
	private static ApplicationContext applicationContext;

	/**
	 * 实现ApplicationContextAware接口的回调方法，设置上下文环境
	 *
	 * @param applicationContext
	 * @throws BeansException
	 */
	public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
		SpringContextUtil.applicationContext = applicationContext;
	}

	/**
	 * @return ApplicationContext
	 */
	public static ApplicationContext getApplicationContext() {
		return applicationContext;
	}

	/**
	 * 获取对象
	 *
	 * @param name
	 * @return Object 一个以所给名字注册的bean的实例
	 * @throws BeansException
	 */
	public static Object getBean(String name) throws BeansException {
		return applicationContext.getBean(name);
	}

	/**
	 * 获取对象
	 *
	 * @param beanClass
	 * @return Object 一个以所给名字注册的bean的实例
	 * @throws BeansException
	 */
	public static Object getBean(Class<?> beanClass) throws BeansException {
		return applicationContext.getBean(beanClass);
	}

	/**
	 * 获取类型为requiredType的对象
	 * 如果bean不能被类型转换，相应的异常将会被抛出（BeanNotOfRequiredTypeException）
	 *
	 * @param name
	 *            bean注册名
	 * @param requiredType
	 *            返回对象类型
	 * @return Object 返回requiredType类型对象
	 * @throws BeansException
	 */
	public static Object getBean(String name, Class<?> requiredType) throws BeansException {
		return applicationContext.getBean(name, requiredType);
	}

	/**
	 * 如果BeanFactory包含一个与所给名称匹配的bean定义，则返回true
	 *
	 * @param name
	 * @return boolean
	 */
	public static boolean containsBean(String name) {
		return applicationContext.containsBean(name);
	}

	/**
	 * 判断以给定名字注册的bean定义是一个singleton还是一个prototype。
	 * 如果与给定名字相应的bean定义没有被找到，将会抛出一个异常（NoSuchBeanDefinitionException）
	 *
	 * @param name
	 * @return boolean
	 * @throws NoSuchBeanDefinitionException
	 */
	public static boolean isSingleton(String name) throws NoSuchBeanDefinitionException {
		return applicationContext.isSingleton(name);
	}

	/**
	 * @param name
	 * @return Class 注册对象的类型
	 * @throws NoSuchBeanDefinitionException
	 */
	public static Class<?> getType(String name) throws NoSuchBeanDefinitionException {
		return applicationContext.getType(name);
	}

	/**
	 * 如果给定的bean名字在bean定义中有别名，则返回这些别名
	 *
	 * @param name
	 * @return 别名数组
	 * @throws NoSuchBeanDefinitionException
	 */
	public static String[] getAliases(String name) throws NoSuchBeanDefinitionException {
		return applicationContext.getAliases(name);
	}
}

1.2 定义bean

package com.test.domain;

/**
 * Created by yangjianzhou on 9/22/15.
 */
public class UserInfo {

    private String  name ;

    private String  password ;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }
}

1.3 在XML中声明Bean

    <bean id="userInfo" class="com.test.domain.UserInfo">
        <property name="name" value="yangjianzhou"/>
        <property name="password" value="123456"/>
    </bean>

1.4 获取bean的基本信息

		UserInfo userInfo = (UserInfo)SpringContextUtil.getBean("userInfo");
		System.out.println(userInfo.getName());

2.InitializingBean的使用

实现InitializingBean接口，实现afterPropertiesSet方法，可以对bean的属性进行改变

2.1实现类

package com.test.domain;

import org.springframework.beans.factory.InitializingBean;

/**
 * Created by yangjianzhou on 9/22/15.
 */
public class UserInfo implements InitializingBean{

    private String  name ;

    private String  password ;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    @Override
    public void afterPropertiesSet() throws Exception {
        this.name = "dbuser";
    }
}

2.2 xml中定义Bean

    <bean id="userInfo" class="com.test.domain.UserInfo">
        <property name="name" value="yangjianzhou"/>
        <property name="password" value="123456"/>
    </bean>

2.3 测试

UserInfo userInfo = (UserInfo)SpringContextUtil.getBean("userInfo");
		System.out.println(userInfo.getName());

3.TransactionSynchronizationManager的使用
在本事务结束之后开启一个事务，一般用一个异步线程开启一个事物，这样就不至于阻塞主线程

		tradeRecordDao.queryById(0l);
		TransactionSynchronizationManager.registerSynchronization(new TransactionSynchronizationAdapter() {
			@Override
			public void afterCommit() {
				asyncEventBus.post(new FundSettleEvent(settleId));
			}
		});

4.在java代码和XML文件中声明Bean，则只使用XML中的Bean
4.1 java代码中声明Bean

package com.test.domain;

import org.springframework.stereotype.Component;

/**
 * Created by yangjianzhou on 9/22/15.
 */
@Component
public class UserInfo {

    private String  name ;

    private String  password ;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

}

4.2 xml中声明Bean

    <bean id="userInfo" class="com.test.domain.UserInfo">
        <property name="name" value="yangjianzhou"/>
        <property name="password" value="123456"/>
    </bean>