DefaultArgumentsClassInitialization - Cookbook - s c h e m a t i c s : c o o k b o o k

Default field values for class initialization

Problem

You want to provide a set of reasonable default values for some fields in a class.

Solution

Use the init-field form, but provide a default expression value along with the field name. For example:

500 Can't connect to 127.0.0.1:8778 (connect: Connection refused)

With this, we can instantiate this either with the default argument value: 500 Can't connect to 127.0.0.1:8778 (connect: Connection refused)

or we can specify the default field value: 500 Can't connect to 127.0.0.1:8778 (connect: Connection refused)

This also works with regular init forms, when we want to do some additional validation or other things before feeding into our object's fields: 500 Can't connect to 127.0.0.1:8778 (connect: Connection refused)

500 Can't connect to 127.0.0.1:8778 (connect: Connection refused)

Discussion

Comments about this recipe

Contributors

-- DannyYoo - 05 Sep 2006

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Current Rev: r1.1 - 05 Sep 2006 - 03:13 GMT - DannyYoo, Revision History:Diffs | r1.1

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