Package randoop.operation

Class NonreceiverTerm

  • All Implemented Interfaces:
    Operation
    public final class NonreceiverTerm
extends CallableOperation
    Represents a value that either cannot (primitive or null values), or we don't care to have (String, Class) be a receiver for a method call as an Operation.

    As an Operation, a value v of type T is formally represented by an operation v : [] → T, with no input types, and the type of the value as the output type. This kind of operation is a ground term — it requires no inputs.

    The execution of this Operation simply returns the value.

    • Field Detail

      • type

        private final Type type
        The Type of this non-receiver term.

      • value

        private final Object value
        The value of this non-receiver term. Must be null, a String, a boxed primitive, or a Class.

    • Constructor Detail

      • NonreceiverTerm

        public NonreceiverTerm​(Type type,
                       Object value)
        Constructs a NonreceiverTerm.
        Parameters:
        type - the type of the term
        value - the value of the term

    • Method Detail

      • isNonreceiverType

        public static boolean isNonreceiverType​(Class<?> c)
        Determines whether the given Class<?> is the type of a non-receiver term.
        Parameters:
        c - the Class<?> object
        Returns:
        true iff the type is primitive, boxed primitive, String, or Class

      • equals

        public boolean equals​(Object o)
        Indicates whether this object is equal to o.
        Overrides:
        equals in class Object

      • hashCode

        public int hashCode()
        Returns a hash code value for this NonreceiverTerm.
        Overrides:
        hashCode in class Object

      • toString

        public String toString()
        Returns string representation of this NonreceiverTerm.
        Overrides:
        toString in class Object

      • getName

        public String getName()
        Description copied from interface: Operation
        Returns the name for the operation.
        Returns:
        the name for this operation

      • execute

        public ExecutionOutcome execute​(Object[] statementInput)
        Performs this operation using the array of input values. Returns the results of execution as an ResultOrException object and can output results to specified PrintStream.
        Specified by:
        execute in class CallableOperation
        Parameters:
        statementInput - array containing appropriate inputs to operation
        Returns:
        NormalExecution object enclosing value of this non-receiver term

      • appendCode

        public void appendCode​(Type declaringType,
                       TypeTuple inputTypes,
                       Type outputType,
                       List<Variable> inputVars,
                       StringBuilder b)
        Produces a Java source code representation of this statement and appends it to the given StringBuilder.

        For NonreceiverTerm, simply adds a code representation of the value to the string builder. Note: this does not explicitly box primitive values.

        Specified by:
        appendCode in class CallableOperation
        Parameters:
        inputVars - ignored
        b - StringBuilder to which string representation is appended
        declaringType - the declaring type for this operation
        inputTypes - the input types for this operation
        outputType - the output type for this operation

      • getValue

        public Object getValue()
        Returns the "value" of an operation that is actually a ground term, meaning a constant of some form. Only null if value is null, otherwise throws an exception if there is not a reasonable meaning of value for type of operation.

        This is a hack to allow randoop.main.GenBranchDir to do mutation.

        Specified by:
        getValue in interface Operation
        Overrides:
        getValue in class CallableOperation
        Returns:
        value of this NonreceiverTerm

      • getType

        public Type getType()
        Return the type.
        Returns:
        the type

      • createNullOrZeroTerm

        static NonreceiverTerm createNullOrZeroTerm​(Type type)
        Returns a NonreceiverTerm holding the zero/false value for the specified class c.
        Parameters:
        type - the type of value desired
        Returns:
        a NonreceiverTerm with a canonical representative of the given type

      • toParsableString

        public String toParsableString​(Type declaringType,
                               TypeTuple inputTypes,
                               Type outputType)
        Returns a string representation of this Operation, which can be read by static parse method for class. For a class C implementing the Operation interface, this method should return a String s such that parsing the string returns an object equivalent to this object, i.e. C.parse(this.s).equals(this).

        Returns a string representing this primitive declaration. The string is of the form:
        TYPE:VALUE
        Where TYPE is the type of the primitive declaration, and VALUE is its value. If VALUE is "null" then the value is null (not the String "null"). If TYPE is "char" then (char)Integer.parseInt(VALUE, 16) yields the character value.

        Examples: 

         String:null                  represents: String x = null
 java.lang.String:""          represents: String x = "";
 String:""                    represents: String x = "";
 String:" "                   represents: String x = " ";
 String:"\""                  represents: String x = "\"";
 String:"\n"                  represents: String x = "\n";
 String:"☺"              represents: String x = "☺";
 java.lang.Object:null        represents: Object x = null;
 [[Ljava.lang.Object;:null    represents: Object[][] = null;
 int:0                        represents: int x = 0;
 boolean:false                represents: boolean x = false;
 char:20                      represents: char x = ' ';
        Note that a string type can be given as both "String" or "java.lang.String".
        Specified by:
        toParsableString in class CallableOperation
        Parameters:
        declaringType - the declaring type for this operation
        inputTypes - the input types for this operation
        outputType - the output type for this operation
        Returns:
        string representation of primitive, String or null value

      • isNonreceivingValue

        public boolean isNonreceivingValue()
        Predicate to indicate whether this object represents a value of a non-receiving type (includes numbers, strings, and null).
        Specified by:
        isNonreceivingValue in interface Operation
        Overrides:
        isNonreceivingValue in class CallableOperation
        Returns:
        true, since all of objects are non-receivers