Package com.saxonica.ee.schema.fsa

Class AutomatonState

java.lang.Object
com.saxonica.ee.schema.fsa.AutomatonState
All Implemented Interfaces:
State
Direct Known Subclasses:
DeterminizedState, NonDeterminizedState
public abstract class AutomatonState extends 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 Details

    • wildcardEdges

      protected Edge[] wildcardEdges

    • EMPTY_EDGE_ARRAY

      public static final Edge[] EMPTY_EDGE_ARRAY

  • Constructor Details

    • AutomatonState

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

  • Method Details

    • 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 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 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(HashMap<AutomatonState,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