How do I place an error message in the corresponding row of a JSF DataTable?

Say I have a editable datatable, with a custom converter that throws an exception if the edited field is somehow wrong, how would I display the error message in the corresponding row of the datatable?

here's some code, as simple as I can make it.

<h:messages />
<h:datatable>
    <h:c开发者_如何学Column>
        <h:inputText value="#{bean.property}">
            <f:converter converterId="PropertyConverter" />
        </h:inputText>
    </h:column>
</h:datatable>

If there's an error in one row, how would I place the error message in that row. I can obviously have a column for errors, but how do I target the corresponding row?

Just add a <h:message /> component inside the same table whose for attribute points to the id of the UIInput component in question.

For example:

<h:datatable>
    <h:column>
        <h:inputText id="someId" value="#{bean.property}">
            <f:converter converterId="PropertyConverter" />
        </h:inputText>
    </h:column>
    <h:column>
        <h:message for="someId" />
    </h:column>
</h:datatable>

or if you want to have it directly after the input element inside the same column:

<h:datatable>
    <h:column>
        <h:inputText id="someId" value="#{bean.property}">
            <f:converter converterId="PropertyConverter" />
        </h:inputText>
        <h:message for="someId" />
    </h:column>
</h:datatable>

No additional code is needed, just throw the ConverterException as usual. JSF will take care about the magic (displaying the message in the right row).