Package jakarta.el

Class ValueExpression

  • All Implemented Interfaces:
    java.io.Serializable

    public abstract class ValueExpression
    extends Expression
    See Also:
    Serialized Form
    • Constructor Detail

      • ValueExpression

        public ValueExpression()
    • Method Detail

      • getValue

        public abstract <T> T getValue​(ELContext context)
        Type Parameters:
        T - The expected type for the result of evaluating this value expression
        Parameters:
        context - The EL context for this evaluation
        Returns:
        The result of evaluating this value expression
        Throws:
        java.lang.NullPointerException - If the supplied context is null
        PropertyNotFoundException - If a property/variable resolution failed because no match was found or a match was found but was not readable
        ELException - Wraps any exception throw whilst resolving a property or variable
      • setValue

        public abstract void setValue​(ELContext context,
                                      java.lang.Object value)
        Parameters:
        context - The EL context for this evaluation
        value - The value to set the property to which this value expression refers
        Throws:
        java.lang.NullPointerException - If the supplied context is null
        PropertyNotFoundException - If a property/variable resolution failed because no match was found
        PropertyNotWritableException - If a property/variable resolution failed because a match was found but was not writable
        ELException - Wraps any exception throw whilst resolving a property or variable
      • isReadOnly

        public abstract boolean isReadOnly​(ELContext context)
        Parameters:
        context - The EL context for this evaluation
        Returns:
        true if this expression is read only otherwise false
        Throws:
        java.lang.NullPointerException - If the supplied context is null
        PropertyNotFoundException - If a property/variable resolution failed because no match was found or a match was found but was not readable
        ELException - Wraps any exception throw whilst resolving a property or variable
      • getType

        public abstract java.lang.Class<?> getType​(ELContext context)
        Parameters:
        context - The EL context for this evaluation
        Returns:
        The type of the result of this value expression
        Throws:
        java.lang.NullPointerException - If the supplied context is null
        PropertyNotFoundException - If a property/variable resolution failed because no match was found or a match was found but was not readable
        ELException - Wraps any exception throw whilst resolving a property or variable
      • getExpectedType

        public abstract java.lang.Class<?> getExpectedType()
      • getValueReference

        public ValueReference getValueReference​(ELContext context)
        Parameters:
        context - The EL context for this evaluation
        Returns:
        This default implementation always returns null
        Since:
        EL 2.2