org.springframework.binding.expression.support

Class AbstractGetValueExpression

java.lang.Object

org.springframework.binding.expression.support.AbstractGetValueExpression

All Implemented Interfaces:

Expression

public abstract class AbstractGetValueExpression
extends java.lang.Object
implements Expression

Trivial helper for concrete expression types that do not support setting their values. Simply throws an unsupported operation exception if setValue(Object, Object) is called. Subclasses must implement getValue(Object).

Author:

Keith Donald

Constructor Summary

Constructors

Constructor and Description
AbstractGetValueExpression()

Method Summary

Modifier and Type	Method and Description
java.lang.String	getExpressionString() Returns the original string used to create this expression, unmodified.
abstract java.lang.Object	getValue(java.lang.Object context) Evaluate this expression in the provided context and return the result of evaluation.
java.lang.Class<?>	getValueType(java.lang.Object context) Returns the most general type that can be passed to the Expression.setValue(Object, Object) method for the given context.
void	setValue(java.lang.Object context, java.lang.Object value) Set this expression in the provided context to the value provided.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

AbstractGetValueExpression

public AbstractGetValueExpression()

Method Detail

getValue

public abstract java.lang.Object getValue(java.lang.Object context)
                                   throws EvaluationException

Description copied from interface: Expression

Evaluate this expression in the provided context and return the result of evaluation.

Specified by:

getValue in interface Expression

Parameters:

context - the context to evaluate this expression in

Returns:

the evaluation result

Throws:

EvaluationException - an exception occurred during expression evaluation

setValue

public void setValue(java.lang.Object context,
                     java.lang.Object value)
              throws EvaluationException

Description copied from interface: Expression

Set this expression in the provided context to the value provided.

Specified by:

setValue in interface Expression

Parameters:

context - the context on which the new value should be set

value - the new value to set

Throws:

EvaluationException - an exception occurred during expression evaluation

getValueType

public java.lang.Class<?> getValueType(java.lang.Object context)

Description copied from interface: Expression

Returns the most general type that can be passed to the Expression.setValue(Object, Object) method for the given context.

Specified by:

getValueType in interface Expression

Parameters:

context - the context to evaluate

Returns:

the most general type of value that can be set on this context, or null if the type information cannot be determined

getExpressionString

public java.lang.String getExpressionString()

Description copied from interface: Expression

Returns the original string used to create this expression, unmodified.

Specified by:

getExpressionString in interface Expression

Returns:

the original expression string