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Switch case problem with JvmTypeReference [message #1798927]

Tue, 27 November 2018 09:22

Eclipse User

With the simple parser rule:

Column:
	'column' name=ValidID ':' columnType=JvmTypeReference ';'
;

Depending on the type I want to generate different strings. Sounds easy, but it doesn't seem to be that obvious.

Within the inferrer I use a switch statement:

switch column.columnType {
	Long: {
		list.add("xyz")
	}
	Integer: {
		list.add("abc")
	}
	default: {
		list.add("z")
	}
}

This leads to a obvious "Cannot cast from JvmTypeReference to Long".

How can I convert the jvmreference or the jvmtype of the reference to the corresponding java type?

Re: Switch case problem with JvmTypeReference [message #1798928 is a reply to message #1798927]

Tue, 27 November 2018 09:30

Eclipse User

Resolve the 'type' reference of the JvmTypeReference. That returns a JvmType. Use the qualifiedName of it to decide that it's a java.lang.Long. A direct usage of the Long type is not possible here, the JVM types are just a representation of the type system.

Re: Switch case problem with JvmTypeReference [message #1798930 is a reply to message #1798928]

Tue, 27 November 2018 09:49

Eclipse User

you may use something like

def static isTypeOf(JvmType type, Class<?> clazz) {
return clazz.canonicalName.equals(type.identifier)
}

or similar

Re: Switch case problem with JvmTypeReference [message #1798932 is a reply to message #1798930]

Tue, 27 November 2018 10:02

Eclipse User

Thank you. The approach with the identifier was my fall back plan. I hoped there might be a more sophisticated way.

Re: Switch case problem with JvmTypeReference [message #1798934 is a reply to message #1798932]

Tue, 27 November 2018 10:22

Eclipse User

You should be able to use Long.name.toFullyQualifiedName with IQualifiedNameConverter if you prefer to use the class constant instead of Strings.

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