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我有两个 bean，SimpleBean 和 ArgumentBean，我正在尝试通过工厂方法连接 bean，并尝试在相同的 bean 定义中替换 bean（我知道这样做很糟糕，但我只是在做一个实验）

即我有以下工厂实用程序类：

    public class FactoryClassUtils {

    public static ArgumentBean getArgumentBean(String firstArg, int secondArg) {
        return new ArgumentBean(firstArg, secondArg);
    }

    public static SimpleBean getSimpleBean(ArgumentBean firstArg, int secondArg) {
        return new SimpleBean(firstArg, secondArg);
    }

    }

并且在spring config xml中指定了下面提到的配置：

        <bean name="argumentBean" class="com.view.spring.factory.factoryclasses.FactoryClassUtils"
        factory-method="getArgumentBean">
        <constructor-arg type="java.lang.String" index="0" value="Hey All!!!" />
         <constructor-arg type="int" index="1" value="20" />
    </bean>

    <bean name="simpleBean"
        class="com.view.spring.factory.factoryclasses.FactoryClassUtils"factory-method="getSimpleBean">
        <constructor-arg>
        <bean class="com.tcs.view.spring.dataobjects.ArgumentBean"/>
        </constructor-arg>
        <constructor-arg type="int" value="20" />
        <property name="argumentBean" ref="argumentBean" /> 
    </bean>

我在上面执行时收到此错误：

    Caused by: org.springframework.beans.NotWritablePropertyException: Invalid property 'argumentBean' of bean class [com.view.spring.dataobjects.SimpleBean]: Bean property 'argumentBean' is not writable or has an invalid setter method. Does the parameter type of the setter match the return type of the getter?
    at org.springframework.beans.BeanWrapperImpl.setPropertyValue(BeanWrapperImpl.java:805)
    at org.springframework.beans.BeanWrapperImpl.setPropertyValue(BeanWrapperImpl.java:655)

值得一提的是，所有的 getter 和 setter 都存在于两个 bean 中。SimpleBean.java 具有类型 ArgumentBean.java 的属性。

简单 Bean 的定义是：

 package com.view.spring.dataobjects;
 public class SimpleBean {
    private ArgumentBean argumentBean;
    int argumentCount;

    public ArgumentBean getArgument() {
        return argumentBean;
    }

    public void setArgument(ArgumentBean argumentBean) {
        this.argumentBean= argumentBean;
    }

    public int getArgumentCount() {
        return argumentCount;
    }

    public void setArgumentCount(int argumentCount) {
        this.argumentCount = argumentCount;
    }

    public SimpleBean(ArgumentBean argument, int argumentCount) {
        this.argumentBean= argument;
        this.argumentCount = argumentCount;
    }

    public void letHimSay() {
        argumentBean.saySomething();
        System.out.println(this.argumentCount);
    }
}

ArgumentBean 的定义是：

package com.view.spring.dataobjects;

public class ArgumentBean {

    private String sayString;
    private int anotherArg;

    public ArgumentBean(String sayString, int anotherArg) {
        this.sayString = sayString;
        this.anotherArg = anotherArg;
    }
    public ArgumentBean(String sayString, Integer anotherArg) {
        this.sayString = sayString;
        this.anotherArg = anotherArg.intValue();
    }

    public ArgumentBean() {

    }

    public void saySomething() {
        System.out.println("We say: "+this.sayString);
        System.out.println(this.anotherArg+" times");
    }
}

如果我从 simpleBean 定义中删除属性标记，我不会收到任何错误。此标记不适用于工厂方法，但在尝试使用构造函数参数时效果很好。有人可以帮我理解这种情况吗？

4

2 回答 2

2

You need to add a setter method for argumentBean in your FactoryClassUtils class

   public class FactoryClassUtils {

    private ArgumentBean argumentBean = null;

    public static ArgumentBean getArgumentBean(String firstArg, int secondArg) {
        return new ArgumentBean(firstArg, secondArg);
    }

    public static SimpleBean getSimpleBean(ArgumentBean firstArg, int secondArg) {
        return new SimpleBean(firstArg, secondArg);
    }

    public void setArgumentBean(Argumentbean argumentBean){
    this.argumentBean = argumentBean;    
    }

}

This is needed since you have defined the argumentbean as a property of FactoryClassUtils in your xml 

<bean name="simpleBean"
    class="com.view.spring.factory.factoryclasses.FactoryClassUtils"factory-method="getSimpleBean">
    <constructor-arg>
    <bean class="com.tcs.view.spring.dataobjects.ArgumentBean"/>
    </constructor-arg>
    <constructor-arg type="int" value="20" />
    <property name="argumentBean" ref="argumentBean" />

It is always good to put setter and getter methods for the property following Java naming convention

于 2014-01-07T13:08:21.817 回答
-1

感谢大家投入时间并为我提供帮助。问题解决了。问题出在我的代码上。SimpleBean.java 中的bean 名称是argument 而不是argumentBean。我指的是变量名，但应该使用 getter 名称，除了“get”后缀（当然是第一个字母小写）。我将配置更改为以下： < property name="argument" ref="argumentBean" /> 并解决了问题。

于 2014-01-08T07:04:15.447 回答