spring注入属性，取到的值一直为null

 <?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="threadPoolTaskExecutor" class="org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor">  
    <property name="corePoolSize" value="10"/>  
    <property name="maxPoolSize" value="30"/>  
    </bean>
    <bean id="mailThread" class="com.zxcl.platform.quartz.MailThread">
          <property name="threadPoolTaskExecutor">  
                <ref local="threadPoolTaskExecutor"/> 
          </property>
          <property name="text">  
            <value type="java.lang.String">"qwer"</value>
          </property>
    </bean>
</beans>

public class MailThread {
    private ThreadPoolTaskExecutor threadPoolTaskExecutor;
    public ThreadPoolTaskExecutor getThreadPoolTaskExecutor() {
        return threadPoolTaskExecutor;
    }
    public void setThreadPoolTaskExecutor(ThreadPoolTaskExecutor threadPoolTaskExecutor) {
        this.threadPoolTaskExecutor = threadPoolTaskExecutor;
    }
    public String getText() {
        return text;
    }
    public void setText(String text) {
        this.text = text;
    }
    private String text;

这种注入方式不对吗？为什么取不到值呢？

 <beans>
    <bean id="threadPoolTaskExecutor" class="org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor">  
    <property name="corePoolSize" value="10"/>  
    <property name="maxPoolSize" value="30"/>  
    </bean>
    <bean id="mailThread" class="com.zxcl.platform.quartz.MailThread">
          <property name="threadPoolTaskExecutor">  
                <ref local="threadPoolTaskExecutor"/> 
          </property>
          <property name="text">  
            <value type="java.lang.String">"qwer"</value>
          </property>
    </bean>
</beans>