/*
* Copyright 2009 Alin Dreghiciu.
*
* Licensed 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.ops4j.pax.swissbox.converter.java.io;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URI;
import java.net.URL;
import org.osgi.service.blueprint.container.Converter;
import org.osgi.service.blueprint.container.ReifiedType;
import static org.ops4j.pax.swissbox.converter.internal.Primitives.*;
import static org.ops4j.pax.swissbox.converter.java.lang.AssignableConverter.*;
import static org.ops4j.pax.swissbox.converter.java.lang.FromNullConverter.*;
/**
* JAVADOC
*
* @author Alin Dreghiciu (adreghiciu@gmail.com)
*/
public class ToInputStreamConverter
implements Converter
{
public static final ToInputStreamConverter INSTANCE = new ToInputStreamConverter();
private final Converter escape;
public ToInputStreamConverter()
{
this.escape = null;
}
public ToInputStreamConverter( final Converter escape )
{
this.escape = escape;
}
public boolean canConvert( final Object sourceObject,
final ReifiedType targetType )
{
return fromNullConverter().canConvert( sourceObject, targetType )
|| assignableConverter().canConvert( sourceObject, targetType )
|| ( InputStream.class.isAssignableFrom( unwrap( targetType.getRawClass() ) )
&& ( sourceObject instanceof URL
|| sourceObject instanceof URI
|| sourceObject instanceof File
|| sourceObject instanceof CharSequence
|| ( escape != null
&& ( escape.canConvert( sourceObject, new ReifiedType( URL.class ) )
|| escape.canConvert( sourceObject, new ReifiedType( URI.class ) )
|| escape.canConvert( sourceObject, new ReifiedType( File.class ) ) ) ) ) );
}
public Object convert( final Object sourceObject,
final ReifiedType targetType )
throws Exception
{
if( !canConvert( sourceObject, targetType ) )
{
throw new Exception(
String.format(
"%s cannot convert an %s", ToInputStreamConverter.class.getSimpleName(), sourceObject.getClass()
)
);
}
if( fromNullConverter().canConvert( sourceObject, targetType ) )
{
return fromNullConverter().convert( sourceObject, targetType );
}
if( assignableConverter().canConvert( sourceObject, targetType ) )
{
return assignableConverter().convert( sourceObject, targetType );
}
return convertToInputStream( sourceObject, targetType );
}
public InputStream convertToInputStream( final Object sourceObject,
final ReifiedType targetType )
throws Exception
{
if( sourceObject instanceof URL )
{
return ( (URL) sourceObject ).openStream();
}
if( sourceObject instanceof URI )
{
return ( (URI) sourceObject ).toURL().openStream();
}
if( sourceObject instanceof File )
{
return new FileInputStream( (File) sourceObject );
}
if( sourceObject instanceof CharSequence )
{
try
{
return new URL( sourceObject.toString() ).openStream();
}
catch( MalformedURLException e )
{
return new FileInputStream( sourceObject.toString() );
}
}
if( escape != null )
{
if( escape.canConvert( sourceObject, new ReifiedType( URL.class ) ) )
{
try
{
return ( (URL) escape.convert( sourceObject, new ReifiedType( URL.class ) ) ).openStream();
}
catch( Exception ignore )
{
// ignore
}
}
if( escape.canConvert( sourceObject, new ReifiedType( URI.class ) ) )
{
try
{
return ( (URI) escape.convert( sourceObject, new ReifiedType( URI.class ) ) ).toURL().openStream();
}
catch( Exception ignore )
{
// ignore
}
}
if( escape.canConvert( sourceObject, new ReifiedType( File.class ) ) )
{
try
{
return new FileInputStream( (File) escape.convert( sourceObject, new ReifiedType( File.class ) ) );
}
catch( Exception ignore )
{
// ignore
}
}
}
throw new Exception( String.format( "Unable to convert number %s to %s", sourceObject, targetType ) );
}
public static ToInputStreamConverter toInputStreamConverter()
{
return INSTANCE;
}
public static ToInputStreamConverter toInputStreamConverter( final Converter escape )
{
return new ToInputStreamConverter( escape );
}
}