我遇到了Spring Framework的问题:@Autowired
为null,但Spring没有抛出任何异常,我无法理解,为什么这些字段为空。
我有一个班级:
package com.processing.gates;
public class Main {
private final ApplicationContext context = Context.getContext();
@Autowired private PaymentGateFactory paymentGateFactory;
@Autowired private CalculatorChooser calculatorChooser;
//...
}
例如,我有以下课程:
package com.processing.gates.comission;
@Component
public class CalculatorChooser {
//...
}
这是我的Spring配置xml:
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:jdbc="http://www.springframework.org/schema/jdbc"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-4.1.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-4.1.xsd
http://www.springframework.org/schema/jdbc
http://www.springframework.org/schema/jdbc/spring-jdbc.xsd">
<context:annotation-config />
<context:component-scan base-package="com.processing.gates"/>
<bean id="logPath" class="java.lang.String"> <!-- путь к папке с логами -->
<constructor-arg value="/home/yoba/NetBeansProjects/processing/gates/log/"/>
</bean>
<!-- ... -->
</beans>
当我尝试用xml编写时:
<bean id="calculator" class="com.processing.gates.comission.CalculatorChooser"/>
从代码中获取:
CalculatorChooser cc = (CalculatorChooser)Context.getContext().getBean("calculator");
它工作正常。但@Autowired不起作用。我怎样才能解决这个问题?谢谢!
答案 0 :(得分:2)
让Spring通过在应用程序上下文文件中声明Main
bean或使用@Component
注释来管理bean,就像你已经为CalculatorChooser
<bean id="mainBean" class="com.processing.gates.Main"/>