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*/

package com.google.refine.importers.tree;

import java.io.Serializable;

/**
 * Interface for all tree-shaped parsers.
 * 
 * This is effectively part of the contract for {@link TreeImportingParserBase}.
 */
public interface TreeReader {
    public enum Token {
        Ignorable,
        StartEntity,
        EndEntity,
        Value
        //append additional tokens only if necessary (most should be just mapped to Value or Ignorable)
    }

    public Token current() throws TreeReaderException; // aka getCurrentToken

    public boolean hasNext() throws TreeReaderException;
    public Token next() throws TreeReaderException;

    public String getFieldName() throws TreeReaderException;
    public String getPrefix();
    
    @Deprecated
    public String getFieldValue() throws TreeReaderException;
    
    public Serializable getValue() throws TreeReaderException;
    
    public int getAttributeCount();
    public String getAttributeValue(int index);
    public String getAttributePrefix(int index);
    public String getAttributeLocalName(int index);
}