今天开发的测试的时候碰到一个问题，就是用Myfaces的SelectOneRadio空间的时候，页面第一次展现没问题，当我使用上一步切换tab再下一步的时候就抛出了异常，异常如下：

Caused by: javax.faces.convert.ConverterException: java.lang.ClassCastException: org.apache.myfaces.shared_impl.renderkit.RendererUtils$1

cannot be cast to java.lang.Boolean

at javax.faces.convert.BooleanConverter.getAsString(BooleanConverter.java:91)

at org.apache.myfaces.shared_impl.renderkit.RendererUtils.getConvertedStringValue(RendererUtils.java:630)

at org.apache.myfaces.shared_impl.renderkit.html.HtmlRadioRendererBase.encodeEnd(HtmlRadioRendererBase.java:91)

at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:624)

... 110 more

Caused by: java.lang.ClassCastException: org.apache.myfaces.shared_impl.renderkit.RendererUtils$1

cannot be cast to java.lang.Boolean

at javax.faces.convert.BooleanConverter.getAsString(BooleanConverter.java:87)

... 113 more



后来在国外网站上面找到了问题所在：



Hello,



the problem still exists in MyFaces Core 1.2.6.



I have a selectOneMenu with a value binding to a boolean property.



In the boolean converter the ClassCastException still occurs.



...

Caused by: javax.faces.convert.ConverterException: java.lang.ClassCastException: org.apache.myfaces.shared_impl.renderkit.RendererUtils$1

cannot be cast to java.lang.Boolean

at javax.faces.convert.BooleanConverter.getAsString(BooleanConverter.java:91)

at org.apache.myfaces.shared_impl.renderkit.RendererUtils.getConvertedStringValue(RendererUtils.java:630)

at org.apache.myfaces.shared_impl.renderkit.html.HtmlRadioRendererBase.encodeEnd(HtmlRadioRendererBase.java:91)

at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:624)

... 110 more

Caused by: java.lang.ClassCastException: org.apache.myfaces.shared_impl.renderkit.RendererUtils$1

cannot be cast to java.lang.Boolean

at javax.faces.convert.BooleanConverter.getAsString(BooleanConverter.java:87)

... 113 more



In RendererUtils there are some tests that value equals NOTHING. However the equals method

of the NOTHING-Serializable isn't overriden. Therefore it has no effect.



Overriding the equals method as in the patch of paul works.





有些东西没有实现，导致了这个问题。这个可能需要你自己简单实现一下源文件然后编译成库文件了，感觉麻烦就换成了SelectOneMenu了。

后面有时间再看了

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