Class ScalarExp

java.lang.Object

org.apache.cayenne.exp.Expression

org.apache.cayenne.exp.ScalarExp

All Implemented Interfaces:

XMLSerializable

public final class ScalarExp
extends Expression

A plain value in the place of an expression, e.g. a constant select column or a whole where clause. A value that is an operand of another expression is not wrapped in a scalar node; it is stored as is.

Since:

5.0

Field Summary

Fields

Modifier and Type	Field	Description
protected Object	value

Fields inherited from class Expression

operands, PRUNED_NODE

Constructor Summary

Constructors

Constructor	Description
ScalarExp(Object... operands)	Creates a scalar with the value passed as the only argument, or a null-valued scalar without arguments.

Method Summary

Modifier and Type	Method	Description
void	appendAsString(Appendable out)	Appends own content as a String to the provided Appendable: the operands separated by the operator.
boolean	equals(Object o)
protected Object	evaluateNode(Object o)	Evaluates itself with object, pushing result on the stack.
protected String	getExpressionOperator(int index)	Returns the operator printed between the operands, before the operand at the given index.
Object	getValue()	Returns the value, resolving an EnumRef to its enum constant.
int	hashCode()
protected boolean	parenthesizeAsOperand()	Whether this node is wrapped in parentheses when printed as an operand of another node.
void	setValue(Object value)
Expression	shallowCopy()	Creates a copy of this expression node, without copying children.

Methods inherited from class Expression

andExp, andExp, appendOperandAsString, deepCopy, encodeAsXML, evaluate, evaluateOperand, exists, expName, filter, filterObjects, first, flattenTree, getOperand, getOperandCount, getPathAliases, isValidParent, match, notExists, notExp, orExp, orExp, params, params, paramsArray, pruneNodeForPrunedChild, setOperand, setOperands, toString, transform, transformExpression, traverse, traverse

Methods inherited from class Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Details

value

protected Object value

Constructor Details

ScalarExp

public ScalarExp(Object... operands)

Creates a scalar with the value passed as the only argument, or a null-valued scalar without arguments.

Method Details

evaluateNode

protected Object evaluateNode(Object o)
                       throws Exception

Description copied from class: Expression

Evaluates itself with object, pushing result on the stack.

Specified by:

evaluateNode in class Expression

Throws:

Exception

shallowCopy

public Expression shallowCopy()

Creates a copy of this expression node, without copying children.

Specified by:

shallowCopy in class Expression

appendAsString

public void appendAsString(Appendable out)
                    throws IOException

Description copied from class: Expression

Appends own content as a String to the provided Appendable: the operands separated by the operator.

Overrides:

appendAsString in class Expression

Throws:

IOException

setValue

public void setValue(Object value)

getValue

public Object getValue()

Returns the value, resolving an EnumRef to its enum constant.

getExpressionOperator

protected String getExpressionOperator(int index)

Description copied from class: Expression

Returns the operator printed between the operands, before the operand at the given index.

Specified by:

getExpressionOperator in class Expression

equals

public boolean equals(Object o)

Overrides:

equals in class Expression

hashCode

public int hashCode()

Overrides:

hashCode in class Expression

parenthesizeAsOperand

protected boolean parenthesizeAsOperand()

Description copied from class: Expression

Whether this node is wrapped in parentheses when printed as an operand of another node. Compound nodes are, leaves and nodes with their own delimiters (function calls, lists) are not.

Overrides:

parenthesizeAsOperand in class Expression