Java 如何在Spring3/WebFlow2中注册自定义转换服务？

我一直试图跟随并用它来指引我，但我没有运气

我定义了一个转换器：

import org.springframework.binding.convert.converters.StringToObject;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.text.ParseException;
import java.util.Date;

public class StringToDateTwoWayConverter  extends StringToObject {
    private DateFormat format = null;

    public StringToDateTwoWayConverter () {
        super(StringToDateTwoWayConverter.class);
        format = new SimpleDateFormat("MM/dd/yyyy");

    }

    @Override
    protected Object toObject(String string, Class targetClass) throws Exception {
        Date date = null;
        try {
            date = format.parse(string);
        } catch (ParseException e) {
            e.printStackTrace();
            return null;
        }
        return date;
    }

    @Override
    protected String toString(Object object) throws Exception {
        Date date = (Date) object;
        return format.format(date);
    }
}

和转换服务：

import org.springframework.binding.convert.service.DefaultConversionService;
import org.springframework.stereotype.Component;

@Component("conversionService")
public class ApplicationConversionService extends DefaultConversionService
{
    @Override
    protected void addDefaultConverters() {
        super.addDefaultConverters();        
        this.addConverter(new StringToDateTwoWayConverter());
        this.addConverter("shortDate", new StringToDateTwoWayConverter());

    }
}

并将其配置为：

<mvc:annotation-driven conversion-service="conversionService" />
<webflow:flow-builder-services id="flowBuilderServices" conversion-service="conversionService" .../>

我完全搞不懂它为什么不起作用。转换服务通过其基类实现ConversionService，因此我看不出问题所在。非常感谢您的任何见解

为了响应下面的回答，我尝试更改服务以实现其他转换服务：

import org.springframework.stereotype.Component;
import org.springframework.core.convert.ConversionService;

import org.springframework.format.support.FormattingConversionService;

@Component ("conversionService")
public class ApplicationConversionService extends FormattingConversionService implements  org.springframework.core.convert.ConversionService
{
    public ApplicationConversionService() {
        this.addConverter(new StringToDateConverter2());

}
}

但现在我以另一种方式失败了：

Caused by: java.lang.IllegalStateException: Cannot convert value of type [com.yadayada.converter.ApplicationConversionService] to required type [org.springframework.binding.convert.ConversionService] for property 'conversionService': no matching editors or conversion strategy found
    at org.springframework.beans.TypeConverterDelegate.convertIfNecessary(TypeConverterDelegate.java:291)
    at org.springframework.beans.TypeConverterDelegate.convertIfNecessary(TypeConverterDelegate.java:155)
    at org.springframework.beans.BeanWrapperImpl.convertForProperty(BeanWrapperImpl.java:461)
    ... 86 more

---

SpringMVC和SpringWebFlow使用不同层次的类型转换器。所以

---

需要

org.springframework.core.convert.ConversionService

，但是

需要

org.springframework.binding.convert.ConversionService

在上面的代码中，你应该写

超级（Date.class）

而不是

超级（StringToDateTwoWayConverter.class）

谢谢！这就解决了问题。我刚刚删除了“”位，因为我最关心的是webflow中的表单绑定，而在常规MVC世界中则更少。现在，原始代码可以正常工作。

Caused by: java.lang.IllegalStateException: Cannot convert value of type [com.yadayada.converter.ApplicationConversionService] to required type [org.springframework.binding.convert.ConversionService] for property 'conversionService': no matching editors or conversion strategy found
    at org.springframework.beans.TypeConverterDelegate.convertIfNecessary(TypeConverterDelegate.java:291)
    at org.springframework.beans.TypeConverterDelegate.convertIfNecessary(TypeConverterDelegate.java:155)
    at org.springframework.beans.BeanWrapperImpl.convertForProperty(BeanWrapperImpl.java:461)
    ... 86 more