Package com.saxonica.ee.schema.fsa

Class AutomatonState

  • All Implemented Interfaces:
    State
    Direct Known Subclasses:
    DeterminizedState, NonDeterminizedState
    public abstract class AutomatonState
extends java.lang.Object
implements State
    Defines a state of a finite state machine used when validating an instance against a complex type. Each State knows about the possible transitions to other states, and knows whether it is a final state. The initial state is referenced from the FiniteStateMachine object, which is itself a property of the UserComplexType against which validation is being performed.

    This class is designed for internal use only.

    • Field Detail

      • wildcardEdges

        protected Edge[] wildcardEdges

      • EMPTY_EDGE_ARRAY

        public static final Edge[] EMPTY_EDGE_ARRAY

    • Constructor Detail

      • AutomatonState

        public AutomatonState​(FiniteStateMachine machine)
        Create a new state
        Parameters:
        machine - the finite state machine to which this State belongs

    • Method Detail

      • isFinalState

        public boolean isFinalState()
        Test whether this state is a final state
        Specified by:
        isFinalState in interface State
        Returns:
        true if this is a final state

      • isConditionallyFinalState

        public boolean isConditionallyFinalState()
        Test whether this state is a final state assuming the counter has reached its minimum value
        Returns:
        true if this state is a final state when the minimum number of occurrences is reached

      • setFinalState

        public void setFinalState​(boolean finalState)
        Set this state to be (or not to be) a final state
        Parameters:
        finalState - true if this state is final

      • getStateNumber

        public int getStateNumber()
        Get the state number
        Returns:
        the state number

      • addSpecificTransition

        public void addSpecificTransition​(Edge edge,
                                  SchemaCompiler compiler)
                           throws SchemaException
        Add a specific transition from this state to another state. This transition accepts a specific element name only.
        Parameters:
        edge - the transition to be added
        compiler - the schema compiler
        Throws:
        SchemaException - if there are two transitions for the same element declaration, that is, if the content model is ambiguous

      • addWildcardTransition

        public void addWildcardTransition​(SchemaCompiler compiler,
                                  Edge transition)
                           throws SchemaException
        Add a wildcard transition from this state to another state.
        Parameters:
        compiler - the schema compiler
        transition - the edge representing the transition
        Throws:
        SchemaException - if the transition cannot be added because it would generate an inconsistency

      • setLimits

        public void setLimits​(int min,
                      int max)
        Set the counter limits
        Parameters:
        min - the minimum number of occurrences of counting edges before a non-counting edge is used
        max - the maximum number of occurrences of counting edges before a non-counting edge is used; the value -1 means unbounded

      • requiresCounter

        public boolean requiresCounter()
        Ask whether this is a counting state
        Returns:
        true if this state requires a counter to be maintained

      • getTransition

        public Edge getTransition​(int token,
                          UserComplexType type)
        Find the edge representing the transition from this state to another state, that is triggered by a given input token
        Specified by:
        getTransition in interface State
        Parameters:
        token - the input token, specifically the fingerprint of an element name
        type - the complex type we are validating against
        Returns:
        the Edge representing the selected transition of the finite state machine, or null if this token is not accepted when in this State (which implies a validation error).

      • listAllowedElements

        public java.lang.String listAllowedElements()
        List the allowed elements in this state as a string, for use in error messages
        Specified by:
        listAllowedElements in interface State
        Returns:
        the list of permitted elements as a string containing comma-separated element names

      • getWildcardEdges

        public Edge[] getWildcardEdges()
        Get an iterator over the wildcard transitions (edges) allowed from this state.
        Specified by:
        getWildcardEdges in interface State
        Returns:
        an Iterator over the edges that represent element wildcards. The objects returned by this Iterator are Edge objects.

      • getEdges

        public java.lang.Iterable<Edge> getEdges()
        Get an iterator over all the transitions (edges) allowed from this state
        Specified by:
        getEdges in interface State
        Returns:
        an Iterator over all the edges from this state. The objects returned by this Iterator are Edge objects.

      • display

        public void display​(java.util.HashMap<AutomatonState,​java.lang.Integer> map)
        Display the finite state machine reachable from this state. This is a diagnostic method for internal use. Output is written to System.err. At present, wildcard transitions are not shown.
        Parameters:
        map - a Hashmap mapping states already processed to the integer values used to represent that state. The method should be called initially with an empty map.

      • displayState

        public void displayState​(Logger err)
        Display the finite state machine reachable from this state. This is a diagnostic method for internal use. Output is written to System.err. At present, wildcard transitions are not shown.
        Parameters:
        err - the output destination destination

      • displayLambdaTransitions

        public void displayLambdaTransitions()
        Display the lambda transitions available from this state

      • setMaxTransition

        public void setMaxTransition​(Edge edge)
        A counting state may have a special Edge that is used when the maxOccurs value is reached. This method sets this edge.
        Parameters:
        edge - the transition to be used when the maxOccurs value is reached

      • getMaxTransition

        public Edge getMaxTransition()
        Get the transition to be used when the maxOccurs value is reached for a counting state.
        Returns:
        the max transition if there is one, else null.

      • serialize

        public void serialize​(SchemaModelSerializer serializer)
               throws XPathException
        Serialize this state as part of the serialization of a schema component model
        Parameters:
        serializer - used to output the model
        Throws:
        XPathException - if any failure occurs