Notice the different syntactic form of the RDF, which specifies that the property value is another resource and not just a plain text string.

请注意rdf的不同语法形式，它将特性值指定为另一种资源而不仅是纯文本字符串。

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The resource adapter might use this method to check that numeric properties are within the acceptable range or to ensure that a string property representing a value from an enumeration is valid.

资源适配器可能用这个方法检查算术属性是否在可以接受的范围之内，或者确保表示枚举值的字符串有效。

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A symbol is a resource identifier (id) that consists of two parts: a text string (symbol name) mapped to an integer value (symbol value).

符号是资源标识符(ID)，由两部分组成：文本字符串(符号名)及其映射的整数值(符号值)。

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