| java.lang.Object javax.el.ELResolver javax.el.ArrayELResolver
ArrayELResolver | public class ArrayELResolver extends ELResolver (Code) | | Defines property resolution behavior on arrays.
This resolver handles base objects that are Java language arrays.
It accepts any object as a property and coerces that object into an
integer index into the array. The resulting value is the value in the array
at that index.
This resolver can be constructed in read-only mode, which means that
ArrayELResolver.isReadOnly will always return true and
ArrayELResolver.setValue will always throw
PropertyNotWritableException .
ELResolver s are combined together using
CompositeELResolver s, to define rich semantics for evaluating
an expression. See the javadocs for
ELResolver for details.
See Also: CompositeELResolver See Also: ELResolver since: JSP 2.1 |
Constructor Summary | |
public | ArrayELResolver() Creates a new read/write ArrayELResolver . | public | ArrayELResolver(boolean isReadOnly) Creates a new ArrayELResolver whose read-only status is
determined by the given parameter. |
Method Summary | |
public Class> | getCommonPropertyType(ELContext context, Object base) If the base object is a Java language array, returns the most general
type that this resolver accepts for the property argument.
Otherwise, returns null .
Assuming the base is an array, this method will always return
Integer.class . | public Iterator<FeatureDescriptor> | getFeatureDescriptors(ELContext context, Object base) Always returns null , since there is no reason to
iterate through set set of all integers.
The
ArrayELResolver.getCommonPropertyType method returns sufficient
information about what properties this resolver accepts.
Parameters: context - The context of this evaluation. Parameters: base - The array to analyze. | public Class> | getType(ELContext context, Object base, Object property) If the base object is an array, returns the most general acceptable type
for a value in this array.
If the base is a array , the
propertyResolved property of the ELContext
object must be set to true by this resolver, before
returning. | public Object | getValue(ELContext context, Object base, Object property) If the base object is a Java language array, returns the value at the
given index. | public boolean | isReadOnly(ELContext context, Object base, Object property) If the base object is a Java language array, returns whether a call to
ArrayELResolver.setValue will always fail.
If the base is a Java language array, the
propertyResolved property of the ELContext
object must be set to true by this resolver, before
returning. | public void | setValue(ELContext context, Object base, Object property, Object val) If the base object is a Java language array, attempts to set the
value at the given index with the given value. |
ArrayELResolver | public ArrayELResolver()(Code) | | Creates a new read/write ArrayELResolver .
|
ArrayELResolver | public ArrayELResolver(boolean isReadOnly)(Code) | | Creates a new ArrayELResolver whose read-only status is
determined by the given parameter.
Parameters: isReadOnly - true if this resolver cannot modifyarrays; false otherwise. |
getCommonPropertyType | public Class> getCommonPropertyType(ELContext context, Object base)(Code) | | If the base object is a Java language array, returns the most general
type that this resolver accepts for the property argument.
Otherwise, returns null .
Assuming the base is an array, this method will always return
Integer.class . This is because arrays accept integers
for their index.
Parameters: context - The context of this evaluation. Parameters: base - The array to analyze. Only bases that are a Java languagearray are handled by this resolver. null if base is not a Java language array;otherwise Integer.class . |
getFeatureDescriptors | public Iterator<FeatureDescriptor> getFeatureDescriptors(ELContext context, Object base)(Code) | | Always returns null , since there is no reason to
iterate through set set of all integers.
The
ArrayELResolver.getCommonPropertyType method returns sufficient
information about what properties this resolver accepts.
Parameters: context - The context of this evaluation. Parameters: base - The array to analyze. Only bases that are a Java languagearray are handled by this resolver. null . |
getType | public Class> getType(ELContext context, Object base, Object property)(Code) | | If the base object is an array, returns the most general acceptable type
for a value in this array.
If the base is a array , the
propertyResolved property of the ELContext
object must be set to true by this resolver, before
returning. If this property is not true after this method
is called, the caller should ignore the return value.
Assuming the base is an array , this method will always
return base.getClass().getComponentType() , which is
the most general type of component that can be stored at any given
index in the array.
Parameters: context - The context of this evaluation. Parameters: base - The array to analyze. Only bases that are Java languagearrays are handled by this resolver. Parameters: property - The index of the element in the array to return the acceptable type for. Will be coerced into an integer, but otherwise ignored by this resolver. If the propertyResolved property of ELContext was set to true , thenthe most general acceptable type; otherwise undefined. throws: PropertyNotFoundException - if the given index is out of bounds for this array. throws: NullPointerException - if context is null throws: ELException - if an exception was thrown while performingthe property or variable resolution. The thrown exceptionmust be included as the cause property of this exception, ifavailable. |
getValue | public Object getValue(ELContext context, Object base, Object property)(Code) | | If the base object is a Java language array, returns the value at the
given index. The index is specified by the property
argument, and coerced into an integer. If the coercion could not be
performed, an IllegalArgumentException is thrown. If the
index is out of bounds, null is returned.
If the base is a Java language array, the
propertyResolved property of the ELContext
object must be set to true by this resolver, before
returning. If this property is not true after this
method is called, the caller should ignore the return value.
Parameters: context - The context of this evaluation. Parameters: base - The array to analyze. Only bases that are Java languagearrays are handled by this resolver. Parameters: property - The index of the value to be returned. Will be coercedinto an integer. If the propertyResolved property of ELContext was set to true , thenthe value at the given index or null if the index was out of bounds. Otherwise, undefined. throws: IllegalArgumentException - if the property could not be coercedinto an integer. throws: NullPointerException - if context is null . throws: ELException - if an exception was thrown while performingthe property or variable resolution. The thrown exceptionmust be included as the cause property of this exception, ifavailable. |
isReadOnly | public boolean isReadOnly(ELContext context, Object base, Object property)(Code) | | If the base object is a Java language array, returns whether a call to
ArrayELResolver.setValue will always fail.
If the base is a Java language array, the
propertyResolved property of the ELContext
object must be set to true by this resolver, before
returning. If this property is not true after this method
is called, the caller should ignore the return value.
If this resolver was constructed in read-only mode, this method will
always return true . Otherwise, it returns
false .
Parameters: context - The context of this evaluation. Parameters: base - The array to analyze. Only bases that are a Java languagearray are handled by this resolver. Parameters: property - The index of the element in the array to return the acceptable type for. Will be coerced into an integer, but otherwise ignored by this resolver. If the propertyResolved property of ELContext was set to true , thentrue if calling the setValue methodwill always fail or false if it is possible thatsuch a call may succeed; otherwise undefined. throws: PropertyNotFoundException - if the given index is out of bounds for this array. throws: NullPointerException - if context is null throws: ELException - if an exception was thrown while performingthe property or variable resolution. The thrown exceptionmust be included as the cause property of this exception, ifavailable. |
setValue | public void setValue(ELContext context, Object base, Object property, Object val)(Code) | | If the base object is a Java language array, attempts to set the
value at the given index with the given value. The index is specified
by the property argument, and coerced into an integer.
If the coercion could not be performed, an
IllegalArgumentException is thrown. If the index is
out of bounds, a PropertyNotFoundException is thrown.
If the base is a Java language array, the
propertyResolved property of the ELContext
object must be set to true by this resolver, before
returning. If this property is not true after this method
is called, the caller can safely assume no value was set.
If this resolver was constructed in read-only mode, this method will
always throw PropertyNotWritableException .
Parameters: context - The context of this evaluation. Parameters: base - The array to be modified. Only bases that are Java languagearrays are handled by this resolver. Parameters: property - The index of the value to be set. Will be coercedinto an integer. Parameters: val - The value to be set at the given index. throws: ClassCastException - if the class of the specified element prevents it from being added to this array. throws: NullPointerException - if context is null . throws: IllegalArgumentException - if the property could not be coercedinto an integer, or if some aspect of the specified element prevents it from being added to this array. throws: PropertyNotWritableException - if this resolver was constructedin read-only mode. throws: PropertyNotFoundException - if the given index is out of bounds for this array. throws: ELException - if an exception was thrown while performingthe property or variable resolution. The thrown exceptionmust be included as the cause property of this exception, ifavailable. |
Methods inherited from javax.el.ELResolver | abstract public Class> getCommonPropertyType(ELContext context, Object base)(Code)(Java Doc) abstract public Iterator<FeatureDescriptor> getFeatureDescriptors(ELContext context, Object base)(Code)(Java Doc) abstract public Class> getType(ELContext context, Object base, Object property)(Code)(Java Doc) abstract public Object getValue(ELContext context, Object base, Object property)(Code)(Java Doc) abstract public boolean isReadOnly(ELContext context, Object base, Object property)(Code)(Java Doc) abstract public void setValue(ELContext context, Object base, Object property, Object value)(Code)(Java Doc)
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