JPQLQueryDeclaration (EclipseLink 2.6.8, API Reference)

All Known Implementing Classes:

AbstractRangeDeclaration, CollectionDeclaration, Declaration, DerivedDeclaration, RangeDeclaration, SubqueryDeclaration, TableDeclaration, UnknownDeclaration
```
public interface JPQLQueryDeclaration
```
A JPQLQueryDeclaration represents either an identification variable declaration or a collection member declaration. For a subquery, the declaration can be a derived path expression.
Provisional API: This interface is part of an interim API that is still under development and expected to change significantly before reaching stability. It is available at this early stage to solicit feedback from pioneering adopters on the understanding that any code that uses this API will almost certainly be broken (repeatedly) as the API evolves.

Version:

2.5

Author:

Pascal Filion

Since:

2.4

Nested Class Summary

Nested Classes
Modifier and Type	Interface and Description
`static class`	`JPQLQueryDeclaration.Type` This enum type defines the various types of declarations supported by both the JPA functional specification and EclipseLink.

Method Summary

Methods
Modifier and Type	Method and Description
`Expression`	`getBaseExpression()` Returns the range variable declaration if this is a range declaration otherwise the collection-valued path expression when this is a collection member declaration.
`Expression`	`getDeclarationExpression()` Returns the declaration expression, which is either an `IdentificationVariableDeclaration` or a `CollectionMemberDeclaration` when part of a FROM clause, otherwise it's either the `DeleteClause` or the `UpdateClause`.
`java.util.List<Join>`	`getJoins()` Returns the `JOIN` expressions defined with this declaration, if supported.
`JPQLQueryDeclaration.Type`	`getType()` Determines the type this declaration represents.
`java.lang.String`	`getVariableName()` Returns the identification variable name that is defining either the abstract schema name or the collection-valued path expression
`boolean`	`hasJoins()` Determines whether the declaration contains JOIN expressions.

- Method Detail
  - getBaseExpression
```
Expression getBaseExpression()
```
    Returns the range variable declaration if this is a range declaration otherwise the collection-valued path expression when this is a collection member declaration.
    
    Returns:
    Either the range variable declaration or the collection-valued path expression
  - getDeclarationExpression
```
Expression getDeclarationExpression()
```
    Returns the declaration expression, which is either an IdentificationVariableDeclaration or a CollectionMemberDeclaration when part of a FROM clause, otherwise it's either the DeleteClause or the UpdateClause.
    
    Returns:
    The root of the declaration expression
  - getJoins
```
java.util.List<Join> getJoins()
```
    Returns the JOIN expressions defined with this declaration, if supported. The list contains the JOIN expressions in ordered they were declared.
    
    Returns:
    The JOIN expressions defined with this declaration or an empty list if this declaration does not support it
  - getType
```
JPQLQueryDeclaration.Type getType()
```
    Determines the type this declaration represents.
    
    Returns:
    One of the possible types
  - getVariableName
```
java.lang.String getVariableName()
```
    Returns the identification variable name that is defining either the abstract schema name or the collection-valued path expression
    
    Returns:
    The identification variable or an empty string if none was defined
  - hasJoins
```
boolean hasJoins()
```
    Determines whether the declaration contains JOIN expressions. This can be true only when JPQLQueryDeclaration.Type.isRange() returns true. A collection member declaration does not have JOIN expressions.
    
    Returns:
    true if at least one JOIN expression was parsed; otherwise false

Interface JPQLQueryDeclaration

Nested Class Summary

Method Summary

Method Detail

getBaseExpression

getDeclarationExpression

getJoins

getType

getVariableName

hasJoins