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CSV manipulation library.
There is a newer version: 1.2.0
/*
 * #%L
 * Nerd4j CSV
 * %%
 * Copyright (C) 2013 Nerd4j
 * %%
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as 
 * published by the Free Software Foundation, either version 3 of the 
 * License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Lesser Public License for more details.
 * 
 * You should have received a copy of the GNU General Lesser Public 
 * License along with this program.  If not, see
 * .
 * #L%
 */
package org.nerd4j.csv.field.converter;

import org.nerd4j.csv.field.CSVFieldConverter;
import org.nerd4j.csv.field.CSVFieldProcessContext;


/**
 * Abstract implementation of the {@link CSVFieldConverter} interface
 * that performs the expected behavior and modifies the {@link CSVFieldProcessContext}
 * accordingly with the framework execution policy.
 * 
 * 
 *  Any custom implementation of the {@link CSVFieldConverter} interface
 *  should extend this class. 
 * 
 *
 * @param  type of the source field format.
 * @param  type of the target field format.
 * 
 * @author Nerd4j Team
 */
public abstract class AbstractCSVFieldConverter implements CSVFieldConverter
{
    
    /** The error message pattern to set into the context in case of failure. */
    private String errorMessagePattern;
    
    
    /**
     * Constructor with parameters.
     * 
     * @param errorMessagePattern error message pattern to set into the context in case of failure.
     */
    public AbstractCSVFieldConverter( final String errorMessagePattern )
    {
        
        super();
        
        if( errorMessagePattern == null || errorMessagePattern.isEmpty() )
            throw new IllegalArgumentException( "The error message pattern is mandatory cannot be null or empty" );
        
        this.errorMessagePattern = errorMessagePattern;
        
    }

    
    /* ******************* */
    /*  INTERFACE METHODS  */
    /* ******************* */

    
    /**
     * {@inheritDoc}
     */
    @Override
    public String getErrorMessagePattern()
    {
        return errorMessagePattern;
    }
    
    /**
     * {@inheritDoc}
     */
    @Override
    public T convert( final S source, final CSVFieldProcessContext context )
    {
        
        try{
        
            final T target = performConversion( source );        
            if( target != null )
            {
                context.setProcessedValue( target );
                return target;
            }
        
        }catch( Exception ex ) {}
        
        context.operationFailed( this );
        return null;
        
    }

    
    /* **************** */
    /*  EXTENSION HOOKS */
    /* **************** */

    
    /**
     * Performs the conversion over the provided source value.
     * 
     *  This method can assume to receive a not null and not
     *  empty value.
     *  
     * 
     * @param source the not null and not empty value to convert.
     * @return the converted value.
     * @throws Exception if the conversion process fails.
     */
    protected abstract T performConversion( final S source ) throws Exception;
    
}