Add nullable attribute to a class in enterprise architect

I am using enterprise architect for UML. I need to generate code from the model. I need have a nullable double att开发者_JS百科ribute in a class. I am able to add a double attribute but don't know how to make it nullable.

Do anyone have any idea how to add a nullable attribute.

There is a small problems with your question, let me first answer the part about the EA, and get to it later.

In UML you denote nullable type as

• +attributeName : TypeName [0..1]
• +fromUser : User [0..1]

in EA this is done in the Multiplicity section Select the class->Hit F9->Select the attribute->Click detail

Lower bound and Upper bound are the fields you are looking for, if each are 1 this attribute has a single value [1] usually not depicted in the diagram

• [0..1] can have a value of null.
• [*] can have any amount of values.
• [1..*] collection that contains at least one value
• [n..m] collection that contains between n and m values. n and m are replaced by concrete numbers

in many languages double is a primitive/value type you can not make it null. If you need to, you have to use Double. Note the first letter is capital.