是不是类名写错了？

配置文件出错了......你的POJO完全没有托管到spring

你把helloManager.xml改为：
<?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"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd">
<bean id="helloWorld" class="cn.com.spring01.helloTest.HelloWorld"></bean>
<bean id="helloChina" class="cn.com.spring01.helloTest.HelloChina"></bean>
<bean id="preson" class="cn.com.spring01.helloTest.Preson">
<property name="helloManager" ref="helloChina"/>
</bean>
</beans>