ca.uhn.hl7v2.model.MessageVisitor Maven / Gradle / Ivy
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package ca.uhn.hl7v2.model;
import ca.uhn.hl7v2.HL7Exception;
import ca.uhn.hl7v2.Location;
/**
* A MessageVisitor can be used to traverse a message structure. Everytime a
* message element is found, the corresponding visitable method is called. If
* a method returns true, the visiting process is continued,
* otherwise abandoned.
*
* A MessageVisitor should usually only be called by
* {@link Visitable#accept(MessageVisitor, Location)}.
*
*/
public interface MessageVisitor {
/**
* Enters a message
* @param message message
* @return true if the visitor shall descend into the nested structures
* @throws HL7Exception if an error occurred while visiting
*/
public boolean start(Message message) throws HL7Exception;
/**
* Leaves a message
* @param message message
* @return true if the visitor shall descend into the nested structures
* @throws HL7Exception if an error occurred while visiting
*/
public boolean end(Message message) throws HL7Exception;
/**
* Enters a group (or message)
* @param group group
* @param location Location object describing the location within the message
* @return true if the visitor shall descend into the nested structures
* @throws HL7Exception if an error occurred while visiting
*/
boolean start(Group group, Location location) throws HL7Exception;
/**
* Leaves a group (or message)
* @param group group
* @param location Location object describing the location within the message
* @return true if the visitor shall continue visiting the parent structure
* @throws HL7Exception if an error occurred while visiting
*/
boolean end(Group group, Location location) throws HL7Exception;
/**
* Enters a segment
* @param segment segment
* @param location Location object describing the location within the message
* @return true if the visitor shall descend into the nested structures
* @throws HL7Exception if an error occurred while visiting
*/
boolean start(Segment segment, Location location) throws HL7Exception;
/**
* Leaves a segment
* @param segment segment
* @param location Location object describing the location within the message
* @return true if the visitor shall continue visiting the parent structure
* @throws HL7Exception if an error occurred while visiting
*/
boolean end(Segment segment, Location location) throws HL7Exception;
/**
* Enters a field. Note that a field is *not* a physical part of the HAPI
* model class hierarchy; it merely encapsulates all repetitions of a specific
* field along with its substructures.
*
* @param field field
* @param location Location object describing the location within the message
* @return true if the visitor shall descend into the nested structures
* @throws HL7Exception if an error occurred while visiting
*/
boolean start(Field field, Location location) throws HL7Exception;
/**
* Leaves a field. Note that a field is *not* a physical part of the HAPI
* model class hierarchy; it merely encapsulates all repetitions of a specific
* field along with its substructures.
*
* @param field field
* @param location Location object describing the location within the message
* @return true if the visitor shall continue visiting the parent structure
* @throws HL7Exception if an error occurred while visiting
*/
boolean end(Field field, Location location) throws HL7Exception;
/**
* Enters a composite
* @param type composite
* @param location Location object describing the location within the message
* @return true if the visitor shall descend into the nested structures
* @throws HL7Exception if an error occurred while visiting
*/
boolean start(Composite type, Location location) throws HL7Exception;
/**
* Leaves a composite
* @param type composite
* @param location Location object describing the location within the message
* @return true if the visitor shall continue visiting the parent structure
* @throws HL7Exception if an error occurred while visiting
*/
boolean end(Composite type, Location location) throws HL7Exception;
/**
* Visits a primitive
* @param type primitive
* @param location Location object describing the location within the message
* @return true if the visitor shall descend into the nested structures
* @throws HL7Exception if an error occurred while visiting
*/
boolean visit(Primitive type, Location location) throws HL7Exception;
}