package ixa.kaflib;
   
   import java.io.Serializable;
   import java.util.List;
   
   public abstract class TreeNode implements Serializable {
   
       /** The ID of the node */
       private String id;
  
      /** The id of the edge between this node and its parent. */
      private String edgeId;
  
      /** Wether the edge between this node and its parent is the "head" or not. */
      private boolean head;
  
      private boolean isTerminal;
  
  
      public TreeNode(String id, boolean head, boolean isTerminal) {
  	this.id = id;
  	this.head = head;
  	this.isTerminal = isTerminal;
      }
  
      public String getId() {
  	return this.id;
      }
  
      public void setId(String id) {
  	this.id = id;
      }
  
      public boolean hasEdgeId() {
  	return this.edgeId != null;
      }
  
      public String getEdgeId() {
  	return this.edgeId;
      }
  
      public void setEdgeId(String edgeId) {
  	this.edgeId = edgeId;
      }
  
      public boolean getHead() {
  	return this.head;
      }
  
      public void setHead(boolean head) {
  	this.head = head;
      }
  
      public boolean isTerminal() {
  	return isTerminal;
      }
  
      public abstract void addChild(TreeNode tn) throws Exception;
  
      public abstract List<TreeNode> getChildren();
  
  }