EE4J Web API 10.0.0 · jakarta.el.MapELResolver

Modifier and Type	Field and Description
private boolean	isReadOnly
private static Class<?>	theUnmodifiableMapClass

Access	Constructor and Description
public	MapELResolver() Creates a new read/write `MapELResolver`.
public	MapELResolver(boolean `true` if this resolver cannot modify maps; `false` otherwise. isReadOnly) Creates a new `MapELResolver` whose read-only status is determined by the given parameter.

Method Summary

Modifier and Type	Method and Description
public Class<?>	Returns: `null` if base is not a `Map`; otherwise `Object.class`. getCommonPropertyType(ELContext The context of this evaluation. context, Object The map to analyze. Only bases of type `Map` are handled by this resolver. base) Implements abstract jakarta.el.ELResolver.getCommonPropertyType. If the base object is a map, returns the most general type that this resolver accepts for the `property` argument.
public Iterator<FeatureDescriptor>	Returns: An `Iterator` containing zero or more (possibly infinitely more) `FeatureDescriptor` objects, each representing a key in this map, or `null` if the base object is not a map. getFeatureDescriptors(ELContext The context of this evaluation. context, Object The map whose keys are to be iterated over. Only bases of type `Map` are handled by this resolver. base) Overrides jakarta.el.ELResolver.getFeatureDescriptors. Deprecated for removal since 5.0. This method will be removed without replacement in EL 6.0 If the base object is a map, returns an `Iterator` containing the set of keys available in the `Map`.
public Class<?>	Returns: If the `propertyResolved` property of `ELContext` was set to `true`, then the most general acceptable type which must be `null` if the either the property or the resolver is read-only; otherwise undefined getType(ELContext The context of this evaluation. context, Object The map to analyze. Only bases of type `Map` are handled by this resolver. base, Object The key to return the acceptable type for. Ignored by this resolver. property) Implements abstract jakarta.el.ELResolver.getType. If the base object is a map, returns the most general acceptable type for a value in this map.
public Object	Returns: If the `propertyResolved` property of `ELContext` was set to `true`, then the value associated with the given key or `null` if the key was not found. Otherwise, undefined. getValue(ELContext The context of this evaluation. context, Object The map to be analyzed. Only bases of type `Map` are handled by this resolver. base, Object The key whose associated value is to be returned. property) Implements abstract jakarta.el.ELResolver.getValue. If the base object is a map, returns the value associated with the given key, as specified by the `property` argument.
public boolean	Returns: If the `propertyResolved` property of `ELContext` was set to `true`, then `true` if calling the `setValue` method will always fail or `false` if it is possible that such a call may succeed; otherwise undefined. isReadOnly(ELContext The context of this evaluation. context, Object The map to analyze. Only bases of type `Map` are handled by this resolver. base, Object The key to return the read-only status for. Ignored by this resolver. property) Implements abstract jakarta.el.ELResolver.isReadOnly. If the base object is a map, returns whether a call to `setValue` will always fail.
public void	setValue(ELContext The context of this evaluation. context, Object The map to be modified. Only bases of type `Map` are handled by this resolver. base, Object The key with which the specified value is to be associated. property, Object The value to be associated with the specified key. val) Implements abstract jakarta.el.ELResolver.setValue. If the base object is a map, attempts to set the value associated with the given key, as specified by the `property` argument.

Inherited from jakarta.el.ELResolver:: convertToType invoke

isReadOnly	back to summary
private boolean isReadOnly

theUnmodifiableMapClass	back to summary
private static Class<?> theUnmodifiableMapClass

MapELResolver	back to summary
public MapELResolver() Creates a new read/write `MapELResolver`.

MapELResolver	back to summary
public MapELResolver(boolean isReadOnly) Creates a new `MapELResolver` whose read-only status is determined by the given parameter. Parameters isReadOnly:boolean `true` if this resolver cannot modify maps; `false` otherwise.

Method Detail

getCommonPropertyType back to summary

getCommonPropertyType	back to summary
public Class<?> getCommonPropertyType(ELContext context, Object base) Implements abstract jakarta.el.ELResolver.getCommonPropertyType. If the base object is a map, returns the most general type that this resolver accepts for the `property` argument. Otherwise, returns `null`. Assuming the base is a `Map`, this method will always return `Object.class`. This is because `Map`s accept any object as a key. Parameters context:ELContext The context of this evaluation. base:Object The map to analyze. Only bases of type `Map` are handled by this resolver. Returns:Class<?> `null` if base is not a `Map`; otherwise `Object.class`. Annotations @Override

public Class<?> getCommonPropertyType(ELContext context, Object base)

Implements abstract jakarta.el.ELResolver.getCommonPropertyType.

If the base object is a map, returns the most general type that this resolver accepts for the property argument. Otherwise, returns null.

Assuming the base is a Map, this method will always return Object.class. This is because Maps accept any object as a key.

Parameters

context:ELContext: The context of this evaluation.
base:Object: The map to analyze. Only bases of type Map are handled by this resolver.

Returns:Class<?>

null if base is not a Map; otherwise Object.class.

Annotations

@Override

getFeatureDescriptors back to summary

getFeatureDescriptors	back to summary
public Iterator<FeatureDescriptor> getFeatureDescriptors(ELContext context, Object base) Overrides jakarta.el.ELResolver.getFeatureDescriptors. Deprecated for removal since 5.0. This method will be removed without replacement in EL 6.0 If the base object is a map, returns an `Iterator` containing the set of keys available in the `Map`. Otherwise, returns `null`. The `Iterator` returned must contain zero or more instances of `java.beans.FeatureDescriptor`. Each info object contains information about a key in the Map, and is initialized as follows: displayName - The return value of calling the `toString` method on this key, or `"null"` if the key is `null`. name - Same as displayName property. shortDescription - Empty string expert - `false` hidden - `false` preferred - `true` In addition, the following named attributes must be set in the returned `FeatureDescriptor`s: `ELResolver#TYPE` - The return value of calling the `getClass()` method on this key, or `null` if the key is `null`. `ELResolver#RESOLVABLE_AT_DESIGN_TIME` - `true` Parameters context:ELContext The context of this evaluation. base:Object The map whose keys are to be iterated over. Only bases of type `Map` are handled by this resolver. Returns:Iterator<FeatureDescriptor> An `Iterator` containing zero or more (possibly infinitely more) `FeatureDescriptor` objects, each representing a key in this map, or `null` if the base object is not a map. Annotations @Deprecated forRemoval:true since:5.0 @Override

public Iterator<FeatureDescriptor> getFeatureDescriptors(ELContext context, Object base)

Overrides jakarta.el.ELResolver.getFeatureDescriptors.

Deprecated

for removal since 5.0.

This method will be removed without replacement in EL 6.0

If the base object is a map, returns an Iterator containing the set of keys available in the Map. Otherwise, returns null.

The Iterator returned must contain zero or more instances of java.beans.FeatureDescriptor. Each info object contains information about a key in the Map, and is initialized as follows:

displayName - The return value of calling the toString method on this key, or "null" if the key is null.
name - Same as displayName property.
shortDescription - Empty string
expert - false
hidden - false
preferred - true

In addition, the following named attributes must be set in the returned FeatureDescriptors:

ELResolver#TYPE - The return value of calling the getClass() method on this key, or null if the key is null.
ELResolver#RESOLVABLE_AT_DESIGN_TIME - true

Parameters

context:ELContext: The context of this evaluation.
base:Object: The map whose keys are to be iterated over. Only bases of type Map are handled by this resolver.

Returns:Iterator<FeatureDescriptor>

An Iterator containing zero or more (possibly infinitely more) FeatureDescriptor objects, each representing a key in this map, or null if the base object is not a map.

Annotations

@Deprecated
forRemoval:true
since:5.0
@Override

getType back to summary

getType	back to summary
public Class<?> getType(ELContext context, Object base, Object property) Implements abstract jakarta.el.ELResolver.getType. If the base object is a map, returns the most general acceptable type for a value in this map. If the base is a `Map`, 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 a `Map`, this method will always return `Object.class` unless the resolver is constructed in read-only mode in which case `null` will be returned. This is because `Map`s accept any object as the value for a given key. Parameters context:ELContext The context of this evaluation. base:Object The map to analyze. Only bases of type `Map` are handled by this resolver. property:Object The key to return the acceptable type for. Ignored by this resolver. Returns:Class<?> If the `propertyResolved` property of `ELContext` was set to `true`, then the most general acceptable type which must be `null` if the either the property or the resolver is read-only; otherwise undefined Annotations @Override Exceptions NullPointerException: if context is `null` ELException: if an exception was thrown while performing the property or variable resolution. The thrown exception must be included as the cause property of this exception, if available.

public Class<?> getType(ELContext context, Object base, Object property)

Implements abstract jakarta.el.ELResolver.getType.

If the base object is a map, returns the most general acceptable type for a value in this map.

If the base is a Map, 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 a Map, this method will always return Object.class unless the resolver is constructed in read-only mode in which case null will be returned. This is because Maps accept any object as the value for a given key.

Parameters

context:ELContext: The context of this evaluation.
base:Object: The map to analyze. Only bases of type Map are handled by this resolver.
property:Object: The key to return the acceptable type for. Ignored by this resolver.

Returns:Class<?>

If the propertyResolved property of ELContext was set to true, then the most general acceptable type which must be null if the either the property or the resolver is read-only; otherwise undefined

Annotations

@Override

Exceptions

NullPointerException:: if context is null
ELException:: if an exception was thrown while performing the property or variable resolution. The thrown exception must be included as the cause property of this exception, if available.

getValue back to summary

getValue	back to summary
public Object getValue(ELContext context, Object base, Object property) Implements abstract jakarta.el.ELResolver.getValue. If the base object is a map, returns the value associated with the given key, as specified by the `property` argument. If the key was not found, `null` is returned. If the base is a `Map`, 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. Just as in `java.util.Map#get`, just because `null` is returned doesn't mean there is no mapping for the key; it's also possible that the `Map` explicitly maps the key to `null`. Parameters context:ELContext The context of this evaluation. base:Object The map to be analyzed. Only bases of type `Map` are handled by this resolver. property:Object The key whose associated value is to be returned. Returns:Object If the `propertyResolved` property of `ELContext` was set to `true`, then the value associated with the given key or `null` if the key was not found. Otherwise, undefined. Annotations @Override Exceptions ClassCastException: if the key is of an inappropriate type for this map (optionally thrown by the underlying `Map`). NullPointerException: if context is `null`, or if the key is null and this map does not permit null keys (the latter is optionally thrown by the underlying `Map`). ELException: if an exception was thrown while performing the property or variable resolution. The thrown exception must be included as the cause property of this exception, if available.

public Object getValue(ELContext context, Object base, Object property)

Implements abstract jakarta.el.ELResolver.getValue.

If the base object is a map, returns the value associated with the given key, as specified by the property argument. If the key was not found, null is returned.

Just as in java.util.Map#get, just because null is returned doesn't mean there is no mapping for the key; it's also possible that the Map explicitly maps the key to null.

Parameters

context:ELContext: The context of this evaluation.
base:Object: The map to be analyzed. Only bases of type Map are handled by this resolver.
property:Object: The key whose associated value is to be returned.

Returns:Object

If the propertyResolved property of ELContext was set to true, then the value associated with the given key or null if the key was not found. Otherwise, undefined.

Annotations

@Override

Exceptions

ClassCastException:: if the key is of an inappropriate type for this map (optionally thrown by the underlying Map).
NullPointerException:: if context is null, or if the key is null and this map does not permit null keys (the latter is optionally thrown by the underlying Map).
ELException:: if an exception was thrown while performing the property or variable resolution. The thrown exception must be included as the cause property of this exception, if available.

isReadOnly back to summary

isReadOnly	back to summary
public boolean isReadOnly(ELContext context, Object base, Object property) Implements abstract jakarta.el.ELResolver.isReadOnly. If the base object is a map, returns whether a call to `setValue` will always fail. If the base is a `Map`, 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`. If a `Map` was created using `java.util.Collections#unmodifiableMap`, this method must return `true`. Unfortunately, there is no Collections API method to detect this. However, an implementation can create a prototype unmodifiable `Map` and query its runtime type to see if it matches the runtime type of the base object as a workaround. Parameters context:ELContext The context of this evaluation. base:Object The map to analyze. Only bases of type `Map` are handled by this resolver. property:Object The key to return the read-only status for. Ignored by this resolver. Returns:boolean If the `propertyResolved` property of `ELContext` was set to `true`, then `true` if calling the `setValue` method will always fail or `false` if it is possible that such a call may succeed; otherwise undefined. Annotations @Override Exceptions NullPointerException: if context is `null` ELException: if an exception was thrown while performing the property or variable resolution. The thrown exception must be included as the cause property of this exception, if available.

public boolean isReadOnly(ELContext context, Object base, Object property)

Implements abstract jakarta.el.ELResolver.isReadOnly.

If the base object is a map, returns whether a call to setValue will always fail.

If this resolver was constructed in read-only mode, this method will always return true.

If a Map was created using java.util.Collections#unmodifiableMap, this method must return true. Unfortunately, there is no Collections API method to detect this. However, an implementation can create a prototype unmodifiable Map and query its runtime type to see if it matches the runtime type of the base object as a workaround.

Parameters

context:ELContext: The context of this evaluation.
base:Object: The map to analyze. Only bases of type Map are handled by this resolver.
property:Object: The key to return the read-only status for. Ignored by this resolver.

Returns:boolean

If the propertyResolved property of ELContext was set to true, then true if calling the setValue method will always fail or false if it is possible that such a call may succeed; otherwise undefined.

Annotations

@Override

Exceptions

NullPointerException:: if context is null
ELException:: if an exception was thrown while performing the property or variable resolution. The thrown exception must be included as the cause property of this exception, if available.

setValue back to summary

setValue	back to summary
public void setValue(ELContext context, Object base, Object property, Object val) Implements abstract jakarta.el.ELResolver.setValue. If the base object is a map, attempts to set the value associated with the given key, as specified by the `property` argument. If the base is a `Map`, 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`. If a `Map` was created using `java.util.Collections#unmodifiableMap`, this method must throw `PropertyNotWritableException`. Unfortunately, there is no Collections API method to detect this. However, an implementation can create a prototype unmodifiable `Map` and query its runtime type to see if it matches the runtime type of the base object as a workaround. Parameters context:ELContext The context of this evaluation. base:Object The map to be modified. Only bases of type `Map` are handled by this resolver. property:Object The key with which the specified value is to be associated. val:Object The value to be associated with the specified key. Annotations @Override Exceptions ClassCastException: if the class of the specified key or value prevents it from being stored in this map. NullPointerException: if context is `null`, or if this map does not permit `null` keys or values, and the specified key or value is `null`. IllegalArgumentException: if some aspect of this key or value prevents it from being stored in this map. ELException: if an exception was thrown while performing the property or variable resolution. The thrown exception must be included as the cause property of this exception, if available. PropertyNotWritableException: if this resolver was constructed in read-only mode, or if the put operation is not supported by the underlying map.

public void setValue(ELContext context, Object base, Object property, Object val)

Implements abstract jakarta.el.ELResolver.setValue.

If the base object is a map, attempts to set the value associated with the given key, as specified by the property argument.

If this resolver was constructed in read-only mode, this method will always throw PropertyNotWritableException.

If a Map was created using java.util.Collections#unmodifiableMap, this method must throw PropertyNotWritableException. Unfortunately, there is no Collections API method to detect this. However, an implementation can create a prototype unmodifiable Map and query its runtime type to see if it matches the runtime type of the base object as a workaround.

Parameters

context:ELContext: The context of this evaluation.
base:Object: The map to be modified. Only bases of type Map are handled by this resolver.
property:Object: The key with which the specified value is to be associated.
val:Object: The value to be associated with the specified key.

Annotations

@Override

Exceptions

ClassCastException:: if the class of the specified key or value prevents it from being stored in this map.
NullPointerException:: if context is null, or if this map does not permit null keys or values, and the specified key or value is null.
IllegalArgumentException:: if some aspect of this key or value prevents it from being stored in this map.
ELException:: if an exception was thrown while performing the property or variable resolution. The thrown exception must be included as the cause property of this exception, if available.
PropertyNotWritableException:: if this resolver was constructed in read-only mode, or if the put operation is not supported by the underlying map.

public Class MapELResolver

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail