Package org.springframework.expression.spel.ast

Class Operator.DescriptorComparison

java.lang.Object

org.springframework.expression.spel.ast.Operator.DescriptorComparison

Enclosing class:

Operator

protected static final class Operator.DescriptorComparison
extends Object

A descriptor comparison encapsulates the result of comparing descriptor for two operands and describes at what level they are compatible.

Method Summary

Modifier and Type	Method	Description
static Operator.DescriptorComparison	checkNumericCompatibility(String leftDeclaredDescriptor, String rightDeclaredDescriptor, String leftActualDescriptor, String rightActualDescriptor)	Return an object that indicates whether the input descriptors are compatible.

Methods inherited from class java.lang.Object

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

Method Details

checkNumericCompatibility

public static Operator.DescriptorComparison checkNumericCompatibility(@Nullable
 String leftDeclaredDescriptor,
 @Nullable
 String rightDeclaredDescriptor,
 @Nullable
 String leftActualDescriptor,
 @Nullable
 String rightActualDescriptor)

Return an object that indicates whether the input descriptors are compatible.

A declared descriptor is what could statically be determined (for example, from looking at the return value of a property accessor method) whilst an actual descriptor is the type of an actual object that was returned, which may differ.

For generic types with unbound type variables, the declared descriptor discovered may be 'Object' but from the actual descriptor it is possible to observe that the objects are really numeric values (for example, ints).

Parameters:

leftDeclaredDescriptor - the statically determinable left descriptor

rightDeclaredDescriptor - the statically determinable right descriptor

leftActualDescriptor - the dynamic/runtime left object descriptor

rightActualDescriptor - the dynamic/runtime right object descriptor

Returns:

a DescriptorComparison object indicating the type of compatibility, if any