XML bean singleton attribute silently ignored [SPR-12167]

[spring-projects-issues]

Alexander Kudrevatykh opened SPR-12167 and commented

In commit 2c3a8a5 support of singleton attribute was dropped
Now if xml contains that attribute it silently ignored, that can cause unexpected behavior in runtime.
I think spring should throw exception in case of such unsupported attributes.

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Affects: 4.0.6

Issue Links:

• Create v4 XML schema [SPR-10437] #15070 Create v4 XML schema
• There is no spring-beans.dtd file inside of the spring-beans-4.1.5.RELEASE jar [SPR-12836] #17433 There is no spring-beans.dtd file inside of the spring-beans-4.1.5.RELEASE jar

Backported to: 4.0.8

[spring-projects-issues]

Juergen Hoeller commented

Note that as of Spring 4.0, we dropped support for pre-2.0 DTDs entirely. And with any 2.0+ DTDs/XSDs, you don't have the 'singleton' attribute declared anymore. Are you still using an older DTD there, or did you turn off XML validation?

In any case, we can certainly throw a proper exception in such a case.

Juergen

[spring-projects-issues]

Alexander Kudrevatykh commented

I know that support was dropped, and after migration to 2.0+ DTD/XSD validation error throwed on this attribute.
Validation is turned on, but old DTD used

<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd">

It would be nice if any exception thrown when using such old DTDs.

[spring-projects-issues]

Juergen Hoeller commented

If we choose to do something 'soft' such as log a warning, we can backport this to 4.0.8 as well.

Juergen

[spring-projects-issues]

Juergen Hoeller commented

When encountering the 'singleton' attribute, we are raising a parse error (turned into an exception) as of Spring Framework 4.1.1 now.

For 4.0.8, we'll just raise a parse warning since quite a few apps might work fine even with some old definition files in use, and we don't want to disrupt them that late in the branch.

Juergen