Package org.apache.el

Class MethodExpressionImpl

    • Constructor Detail

      • MethodExpressionImpl

        public MethodExpressionImpl()
    • Method Detail

      • equals

        public boolean equals​(Object obj)
        Determines whether the specified object is equal to this Expression.

        The result is true if and only if the argument is not null, is an Expression object that is the of the same type (ValueExpression or MethodExpression), and has an identical parsed representation.

        Note that two expressions can be equal if their expression Strings are different. For example, ${fn1:foo()} and ${fn2:foo()} are equal if their corresponding FunctionMappers mapped fn1:foo and fn2:foo to the same method.

        Specified by:
        equals in class Expression
        obj - the Object to test for equality.
        true if obj equals this Expression; false otherwise.
        See Also:
        Hashtable, Object.equals(java.lang.Object)
      • getExpressionString

        public String getExpressionString()
        Returns the original String used to create this Expression, unmodified.

        This is used for debugging purposes but also for the purposes of comparison (e.g. to ensure the expression in a configuration file has not changed).

        This method does not provide sufficient information to re-create an expression. Two different expressions can have exactly the same expression string but different function mappings. Serialization should be used to save and restore the state of an Expression.

        Specified by:
        getExpressionString in class Expression
        The original expression String.
        See Also:
      • hashCode

        public int hashCode()
        Returns the hash code for this Expression.

        See the note in the equals(java.lang.Object) method on how two expressions can be equal if their expression Strings are different. Recall that if two objects are equal according to the equals(Object) method, then calling the hashCode method on each of the two objects must produce the same integer result. Implementations must take special note and implement hashCode correctly.

        Specified by:
        hashCode in class Expression
        The hash code for this Expression.
        See Also:
        equals(java.lang.Object), Hashtable, Object.hashCode()
      • invoke

        public Object invoke​(ELContext context,
                             Object[] params)
                      throws PropertyNotFoundException,
        Evaluates the expression relative to the provided context, invokes the method that was found using the supplied parameters, and returns the result of the method invocation.
        Specified by:
        invoke in class MethodExpression
        context - The context of this evaluation.
        params - The parameters to pass to the method, or null if no parameters.
        the result of the method invocation (null if the method has a void return type).
        NullPointerException - if context is null or the base object is null on the last resolution.
        PropertyNotFoundException - if one of the property resolutions failed because a specified variable or property does not exist or is not readable.
        MethodNotFoundException - if no suitable method can be found.
        ELException - if an exception was thrown while performing property or variable resolution. The thrown exception must be included as the cause property of this exception, if available. If the exception thrown is an InvocationTargetException, extract its cause and pass it to the ELException constructor.
        See Also:
        MethodExpression.invoke(javax.el.ELContext, java.lang.Object[])
      • isParametersProvided

        public boolean isParametersProvided()
        isParametersProvided in class MethodExpression
        This default implementation always returns false
        EL 3.0
      • isParmetersProvided

        public boolean isParmetersProvided()
        isParmetersProvided in class MethodExpression
        Always false
        EL 2.2 Note: The spelling mistake is deliberate. isParmetersProvided() - Specification definition isParametersProvided() - Corrected spelling