/*

  * 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.commons.flatfile.util;

 import java.io.InputStream;

 import java.lang.reflect.Constructor;

 /**

  * Basic FilterFactory that creates an instance of a given InputStream subclass with a (InputStream) constructor.

  * @version $Revision: 758023 $ $Date: 2009-03-24 16:09:19 -0500 (Tue, 24 Mar 2009) $

  */

 public class BasicFilterFactory extends FilterFactory {

     private static final long serialVersionUID = 9080292216759574895L;

     private static final Class<?>[] PARAMETER_TYPES = new Class[] { InputStream.class };

     private static final String HIERARCHY_ERROR = " does not inherit from "

             + InputStream.class.getName();

     private Constructor<? extends InputStream> constructor;

     /**

      * Create a new BasicFilterFactory instance.

      * @param clazz (Filter)InputStream type to instantiate.

      */

     public BasicFilterFactory(Class<? extends InputStream> clazz) {

         if (!InputStream.class.isAssignableFrom(clazz)) {

             throw new IllegalArgumentException(clazz + HIERARCHY_ERROR);

         }

         try {

             constructor = clazz.getConstructor(PARAMETER_TYPES);

         } catch (Exception e) {

             throw new IllegalArgumentException(clazz + ": " + e.toString());

         }

     }

     /**

      * {@inheritDoc}

      */

     protected InputStream iGetFilter(InputStream markIsSupported) {

         if (constructor == null) {

             throw new IllegalStateException();

         }

         try {

             return constructor.newInstance(new Object[] { markIsSupported });

         } catch (Exception e) {

             throw new RuntimeException(e);

         }

     }

 }