org.eclipse.persistence.jpa.jpql.parser

Enum IdentifierRole

java.lang.Object

java.lang.Enum<IdentifierRole>

org.eclipse.persistence.jpa.jpql.parser.IdentifierRole

All Implemented Interfaces:

java.io.Serializable, java.lang.Comparable<IdentifierRole>

public enum IdentifierRole
extends java.lang.Enum<IdentifierRole>

A role describes the purpose of the JPQL identifier.

Version:

2.5

Author:

Pascal Filion

Since:

2.3

Enum Constant Summary

Enum Constants

Enum Constant and Description
AGGREGATE Indicates the identifier aggregates two expressions together.
CLAUSE Indicates the identifier is used to create a clause.
COMPLEMENT Indicates the identifier is used to complement an expression, it is not required for creating an expression.
COMPOUND_FUNCTION Indicates the identifier is a kind of function, it does not return a value but it is used to perform some operation over an expression.
FUNCTION Indicates the identifier is used to create a function, it has some parameters and returns a value.
UNUSED Indicates the identifier is not part of the language but it has been reserved for future use.

Method Summary

Modifier and Type	Method and Description
static IdentifierRole	valueOf(java.lang.String name) Returns the enum constant of this type with the specified name.
static IdentifierRole[]	values() Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Detail

AGGREGATE

public static final IdentifierRole AGGREGATE

Indicates the identifier aggregates two expressions together. The identifiers are AND, OR, and the arithmetic operators.

CLAUSE

public static final IdentifierRole CLAUSE

Indicates the identifier is used to create a clause. They are the root of a portion of the query. An example is SELECT.

COMPLEMENT

public static final IdentifierRole COMPLEMENT

Indicates the identifier is used to complement an expression, it is not required for creating an expression. Examples are AS or OUTER.

COMPOUND_FUNCTION

public static final IdentifierRole COMPOUND_FUNCTION

Indicates the identifier is a kind of function, it does not return a value but it is used to perform some operation over an expression. The expression can have an expression before and after but it's not used to aggregate those two expression. An example is x MEMBER y.

FUNCTION

public static final IdentifierRole FUNCTION

Indicates the identifier is used to create a function, it has some parameters and returns a value. An example is ABS(x), usually the identifier has some values encapsulated with parenthesis.

Note: TRUE, FALSE, NULL, CURRENT_DATE, CURRENT_TIME, CURRENT_TIMESTAMP are considered functions.

UNUSED

public static final IdentifierRole UNUSED

Indicates the identifier is not part of the language but it has been reserved for future use. The identifiers are BIT_LENGTH, CHAR_LENGTH, CHARACTER_LENGTH, POSITION, and UNKNOWN.

Method Detail

values

public static IdentifierRole[] 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 (IdentifierRole c : IdentifierRole.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static IdentifierRole valueOf(java.lang.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:

java.lang.IllegalArgumentException - if this enum type has no constant with the specified name

java.lang.NullPointerException - if the argument is null