# PDFileSpecification.java

    /*
     * Licensed to the Apache Software Foundation (ASF) under one or more
     * contributor license agreements.  See the NOTICE file distributed with
     * this work for additional information regarding copyright ownership.
     * The ASF licenses this file to You under the Apache License, Version 2.0
     * (the "License"); you may not use this file except in compliance with
     * the License.  You may obtain a copy of the License at
     *
     *      http://www.apache.org/licenses/LICENSE-2.0
     *
     * Unless required by applicable law or agreed to in writing, software
     * distributed under the License is distributed on an "AS IS" BASIS,
     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     * See the License for the specific language governing permissions and
     * limitations under the License.
     */
    package org.apache.pdfbox.pdmodel.common.filespecification;

    import java.io.IOException;

    import org.apache.pdfbox.cos.COSBase;
    import org.apache.pdfbox.cos.COSDictionary;
    import org.apache.pdfbox.cos.COSString;

    import org.apache.pdfbox.pdmodel.common.COSObjectable;

    /**
     * This represents a file specification.
     *
     * @author Ben Litchfield
     */
    public abstract class PDFileSpecification implements COSObjectable
    {

        /**
         * A file specification can either be a COSString or a COSDictionary.  This
         * will create the file specification either way.
         *
         * @param base The cos object that describes the fs.
         *
         * @return The file specification for the COSBase object.
         *
         * @throws IOException If there is an error creating the file spec.
         */
        public static PDFileSpecification createFS( COSBase base ) throws IOException
        {
            PDFileSpecification retval = null;
            if( base == null )
            {
                //then simply return null
            }
            else if( base instanceof COSString )
            {
                retval = new PDSimpleFileSpecification( (COSString)base );
            }
            else if( base instanceof COSDictionary )
            {
                retval = new PDComplexFileSpecification( (COSDictionary)base );
            }
            else
            {
                throw new IOException( "Error: Unknown file specification " + base );
            }
            return retval;
        }

        /**
         * This will get the file name.
         *
         * @return The file name.
         */
        public abstract String getFile();

        /**
         * This will set the file name.
         *
         * @param file The name of the file.
         */
        public abstract void setFile( String file );
    }