ILOG JRules User Guide > Creating Rule Projects > Concepts > Vocabulary > Phrase Templates > Placeholders

Vocabulary phrase templates contain placeholders, which represent gaps in phrases that can be filled in automatically or manually when editing rules. Placeholders are identified by curly brackets {}.

There are three types of placeholders:

Subject Placeholder

Subject placeholders appear in navigation phrases. The subject is a business term that you can edit in the BOM Editor. The subject corresponds to the return type a member.

The subject placeholder is optional. When used in rules, the subject placeholder automatically takes the appropriate number and article for the context.

In the placeholder text, the subject needs to be specified using the singular form, without article.

Subject Placeholder

{this} Placeholder

The {this} placeholder represents the declaring class of a member. You cannot use this placeholder in the verbalization of static members.

For example, for an attribute lastName of type String in class Customer, you can specify the following phrase template:

{this} Placeholder

If there is no ambiguity, you can choose to write simplified phrase templates by not using the {this} placeholder. See Simplified Phrase Templates.

Argument Placeholder

Argument placeholders represent the arguments of methods, and are represented by the index of the argument.

For example, in the action phrase in {this}, display the message {0} , which is the verbalization of the method Session.displayMessage(String), {0} is the argument placeholder for a String.

Argument Placeholde

Related Concepts

Phrase Templates

Related Tasks

Editing and Creating Phrases

Related Reference

BOM Editor

Related Samples and Tutorials

Tutorial: Defining a Vocabulary