Package javax.el

Class ELResolver

    • Constructor Summary

      Constructors 
      Constructor Description
      ELResolver()  
    • Method Summary

      All Methods Instance Methods Abstract Methods Concrete Methods 
      Modifier and Type Method Description
      java.lang.Object convertToType​(ELContext context, java.lang.Object obj, java.lang.Class<?> type)
      Converts the given object to the given type.
      abstract java.lang.Class<?> getCommonPropertyType​(ELContext context, java.lang.Object base)
      Obtain the most common type that is acceptable for the given base object.
      abstract java.util.Iterator<java.beans.FeatureDescriptor> getFeatureDescriptors​(ELContext context, java.lang.Object base)
      Obtain the feature descriptors for the resolvable properties of the given object.
      abstract java.lang.Class<?> getType​(ELContext context, java.lang.Object base, java.lang.Object property)  
      abstract java.lang.Object getValue​(ELContext context, java.lang.Object base, java.lang.Object property)  
      java.lang.Object invoke​(ELContext context, java.lang.Object base, java.lang.Object method, java.lang.Class<?>[] paramTypes, java.lang.Object[] params)
      Invokes a method on the the given object.
      abstract boolean isReadOnly​(ELContext context, java.lang.Object base, java.lang.Object property)  
      abstract void setValue​(ELContext context, java.lang.Object base, java.lang.Object property, java.lang.Object value)  
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Constructor Detail

      • ELResolver

        public ELResolver()
    • Method Detail

      • getValue

        public abstract java.lang.Object getValue​(ELContext context,
                                                  java.lang.Object base,
                                                  java.lang.Object property)
        Parameters:
        context - The EL context for this evaluation
        base - The base object on which the property is to be found
        property - The property whose value is to be returned
        Returns:
        the value of the provided property
        Throws:
        java.lang.NullPointerException - If the supplied context is null
        PropertyNotFoundException - If the base/property combination provided to the resolver is one that the resolver can handle but no match was found or a match was found but was not readable
        ELException - Wraps any exception throw whilst resolving the property
      • invoke

        public java.lang.Object invoke​(ELContext context,
                                       java.lang.Object base,
                                       java.lang.Object method,
                                       java.lang.Class<?>[] paramTypes,
                                       java.lang.Object[] params)
        Invokes a method on the the given object. This default implementation always returns null.
        Parameters:
        context - The EL context for this evaluation
        base - The base object on which the method is to be found
        method - The method to invoke
        paramTypes - The types of the parameters of the method to invoke
        params - The parameters with which to invoke the method
        Returns:
        Always null
        Since:
        EL 2.2
      • getType

        public abstract java.lang.Class<?> getType​(ELContext context,
                                                   java.lang.Object base,
                                                   java.lang.Object property)
        Parameters:
        context - The EL context for this evaluation
        base - The base object on which the property is to be found
        property - The property whose type is to be returned
        Returns:
        the type of the provided property
        Throws:
        java.lang.NullPointerException - If the supplied context is null
        PropertyNotFoundException - If the base/property combination provided to the resolver is one that the resolver can handle but no match was found or a match was found but was not readable
        ELException - Wraps any exception throw whilst resolving the property
      • setValue

        public abstract void setValue​(ELContext context,
                                      java.lang.Object base,
                                      java.lang.Object property,
                                      java.lang.Object value)
        Parameters:
        context - The EL context for this evaluation
        base - The base object on which the property is to be found
        property - The property whose value is to be set
        value - The value to set the property to
        Throws:
        java.lang.NullPointerException - If the supplied context is null
        PropertyNotFoundException - If the base/property combination provided to the resolver is one that the resolver can handle but no match was found
        PropertyNotWritableException - If the base/property combination provided to the resolver is one that the resolver can handle but the property was not writable
        ELException - Wraps any exception throw whilst resolving the property
      • isReadOnly

        public abstract boolean isReadOnly​(ELContext context,
                                           java.lang.Object base,
                                           java.lang.Object property)
        Parameters:
        context - The EL context for this evaluation
        base - The base object on which the property is to be found
        property - The property to be checked for read only status
        Returns:
        true if the identified property is read only, otherwise false
        Throws:
        java.lang.NullPointerException - If the supplied context is null
        PropertyNotFoundException - If the base/property combination provided to the resolver is one that the resolver can handle but no match was found
        ELException - Wraps any exception throw whilst resolving the property
      • getFeatureDescriptors

        public abstract java.util.Iterator<java.beans.FeatureDescriptor> getFeatureDescriptors​(ELContext context,
                                                                                               java.lang.Object base)
        Obtain the feature descriptors for the resolvable properties of the given object.
        Parameters:
        context - The context in which the examination takes place
        base - The object to examine
        Returns:
        An iterator, possibly empty, of feature descriptors of the given object
      • getCommonPropertyType

        public abstract java.lang.Class<?> getCommonPropertyType​(ELContext context,
                                                                 java.lang.Object base)
        Obtain the most common type that is acceptable for the given base object.
        Parameters:
        context - The context in which the examination takes place
        base - The object to examine
        Returns:
        {code null} if the most common type cannot be determine, otherwise the most common type
      • convertToType

        public java.lang.Object convertToType​(ELContext context,
                                              java.lang.Object obj,
                                              java.lang.Class<?> type)
        Converts the given object to the given type. This default implementation always returns null.
        Parameters:
        context - The EL context for this evaluation
        obj - The object to convert
        type - The type to which the object should be converted
        Returns:
        Always null
        Since:
        EL 3.0