java - 模板设计模式的 Spring 配置问题

Question

我在 Spring 使用模板设计模式时遇到配置问题。

应用程序.java

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = { "Spring-Module.xml" })
public class App {

    @Autowired
    @Qualifier("userExecutor")
    private IExecutor userExecutor;

    public void print(){
        System.out.println(userExecutor.execute());
    }
}

Spring-Module.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans default-lazy-init="true"
    xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:tx="http://www.springframework.org/schema/tx" xmlns:context="http://www.springframework.org/schema/context"
    xmlns:aop="http://www.springframework.org/schema/aop" xmlns:util="http://www.springframework.org/schema/util"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans-4.2.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context-4.2.xsd">

    <context:annotation-config />
    <context:component-scan base-package="com.ravi" />

</beans>

IExecutor.java

public interface IExecutor {
    public Object execute();
}

抽象执行器.java

public abstract class AbstractExecutor implements IExecutor {

    private IInputPropertyBean inputObject;

    private IOutputPropertyBean outputObject;

    public abstract IAttribute getInputValues(Object inputObject);

    public abstract IAttribute process(IAttribute inputPropertyBean);

    public abstract IOutputPropertyBean getOutputValues(IAttribute outputPropertyBean, IOutputPropertyBean outObject);

    public AbstractExecutor(IInputPropertyBean inputObject, IOutputPropertyBean outputObject) {
        this.inputObject = inputObject;
        this.outputObject = outputObject;
    }

    @Override
    public Object execute() {
        IAttribute inputAttribute = getInputValues(inputObject);
        IAttribute outputAttribute = process(inputAttribute);
        outputObject = (IOutputPropertyBean) getOutputValues(outputAttribute, outputObject);
        return outputObject;
    }

}

抽象用户执行器.java

public abstract class AbstractUserExecutor extends AbstractExecutor {

    public AbstractUserExecutor(IInputPropertyBean inputObject, IOutputPropertyBean outputObject) {
        super(inputObject, outputObject);
    }

    @Override
    public IAttribute getInputValues(Object inputObject) {
        System.out.println("getInputValues");
        return null;
    }

    @Override
    public IOutputPropertyBean getOutputValues(IAttribute outputPropertyBean, IOutputPropertyBean outObject) {
        System.out.println("getOutputValues");
        return null;
    }

}

用户执行器.java

@Repository("userExecutor")
public class UserExecutor extends AbstractUserExecutor {

    @Autowired
    @Qualifier("userInput")
    private IInputPropertyBean inputObject;

    @Autowired
    @Qualifier("userOutput")
    private IOutputPropertyBean outputObject;


    public UserExecutor(IInputPropertyBean inputObject, IOutputPropertyBean outputObject) {
        super(inputObject, outputObject);
    }

    @Override
    public IAttribute process(IAttribute inputPropertyBean) {
        System.out.println("process");  
        return null;
    }
}

IInputPropertyBean.java

public interface IInputPropertyBean {}

IOutputPropertyBean.java

public interface IOutputPropertyBean { }

用户输入.java

@Component("userInput")
public class UserInput implements IInputPropertyBean {

    private String name;

    public String getName() {
        return name;
    }

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

}

用户输出.java

@Component("userOutput")
public class UserOutput implements IOutputPropertyBean {

    private String username;

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }
}

IAttribute.java

public interface IAttribute { }

用户.java

@Component
public class User implements IAttribute{
}

Answer 1

我已经在我的本地环境中尝试了您的代码。我遇到的问题是 UserExecutor、AbstractUserExecutor 和 AbstractExecutor 类缺少默认构造函数。添加这些后它起作用了。

所以我认为您的问题是缺少默认构造函数。尝试添加它们，让我知道它是否有效。