public class DeclarationExpression extends BinaryExpression
Represents one or more local variables. Typically it is a single local variable
declared by name with an expression like "def foo" or with type "String foo". However,
the multiple assignment feature allows you to create two or more variables using
an expression like: def (x, y) = [1, 2]
.
You can access the left hand side of a declaration using the
"Expression getLeftExpression()
" method. In which case you might then
use instanceof
and casting to perform operations specific to a
single local variable (VariableExpression
) or for the multiple
assignment case (TupleExpression
).
Alternatively, if isMultipleAssignmentDeclaration()
is false
you can use the method "VariableExpression getVariableExpression()
" method.
Similarly, if isMultipleAssignmentDeclaration()
is true
you can use the method "TupleExpression getTupleExpression()
" method.
Calling either of these expression getters when the "isMultipleAssignment" condition
is not appropriate is unsafe and will result in a ClassCastException
.
Fields inherited from class | Fields |
---|---|
class Expression |
EMPTY_ARRAY |
Constructor and description |
---|
DeclarationExpression
(VariableExpression left, Token operation, Expression right) Creates a DeclarationExpression for VariableExpressions like "def x" or "String y = 'foo'". |
DeclarationExpression
(Expression left, Token operation, Expression right) Creates a DeclarationExpression for Expressions like "def (x, y) = [1, 2]" |
Type Params | Return Type | Name and description |
---|---|---|
|
public String |
getText() |
|
public TupleExpression |
getTupleExpression() This method returns the left hand side of the declaration cast to the TupleExpression type. |
|
public VariableExpression |
getVariableExpression() This method returns the left hand side of the declaration cast to the VariableExpression type. |
|
public boolean |
isMultipleAssignmentDeclaration() This method tells you if this declaration is a multiple assignment declaration, which has the form "def (x, y) = ..." in Groovy. |
|
public void |
setLeftExpression(Expression leftExpression) This method sets the leftExpression for this BinaryExpression. |
|
public void |
setRightExpression(Expression rightExpression) |
|
public Expression |
transformExpression(ExpressionTransformer transformer) |
|
public void |
visit(GroovyCodeVisitor visitor) |
Creates a DeclarationExpression for VariableExpressions like "def x" or "String y = 'foo'".
left
- the left hand side of a variable declarationoperation
- the operation, typically an assignment operatorright
- the right hand side of a declarationCreates a DeclarationExpression for Expressions like "def (x, y) = [1, 2]"
left
- the left hand side of a declaration. Must be either a VariableExpression or
a TupleExpression with at least one element.operation
- the operation, typically an assignment operatorright
- the right hand side of a declarationThis method returns the left hand side of the declaration cast to the TupleExpression type. This is an unsafe method to call. In a single assignment statement, the left hand side will be a VariableExpression and a ClassCastException will occur. If you invoke this method then be sure to invoke isMultipleAssignmentDeclaration() first to check that it is safe to do so. If that method returns true then this method is safe to call.
This method returns the left hand side of the declaration cast to the VariableExpression type. This is an unsafe method to call. In a multiple assignment statement, the left hand side will be a TupleExpression and a ClassCastException will occur. If you invoke this method then be sure to invoke isMultipleAssignmentDeclaration() first to check that it is safe to do so. If that method returns true then this method is safe to call.
This method tells you if this declaration is a multiple assignment declaration, which has the form "def (x, y) = ..." in Groovy. If this method returns true, then the left hand side is an ArgumentListExpression. Do not call "getVariableExpression()" on this object if this method returns true, instead use "getLeftExpression()".
This method sets the leftExpression for this BinaryExpression. The parameter must be either a VariableExpression or a TupleExpression with one or more elements.
leftExpression
- either a VariableExpression or a TupleExpression with one or more elements.Copyright © 2003-2021 The Apache Software Foundation. All rights reserved.