Package org.gcube.informationsystem.resourceregistry.queries.operators

Enum FieldOperator

  • All Implemented Interfaces:
    Serializable, Comparable<FieldOperator>
    public enum FieldOperator
extends Enum<FieldOperator>
    Author:
    Luca Frosini (ISTI - CNR) Methods: also called "Field Operators" SQL Methods are similar to SQL functions but they apply to values. In Object Oriented paradigm they are called "methods", as functions related to a class. So what's the difference between a function and a method? This is a SQL function: SELECT sum( salary ) FROM employee This is a SQL method: SELECT salary.toJSON() FROM employee As you can see the method is executed against a field/value. Methods can receive parameters, like functions. You can concatenate N operators in sequence. See https://orientdb.com/docs/3.0.x/sql/SQL-Where.html#methods http://orientdb.com/docs/3.0.x/sql/SQL-Methods.html

    • Method Detail

      • values

        public static FieldOperator[] values()
        Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows: 
        for (FieldOperator c : FieldOperator.values())
    System.out.println(c);
        Returns:
        an array containing the constants of this enum type, in the order they are declared

      • valueOf

        public static FieldOperator valueOf​(String name)
        Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)
        Parameters:
        name - the name of the enum constant to be returned.
        Returns:
        the enum constant with the specified name
        Throws:
        IllegalArgumentException - if this enum type has no constant with the specified name
        NullPointerException - if the argument is null