org.eclipse.sisu.space.ZipEntryIterator Maven / Gradle / Ivy
/*******************************************************************************
* Copyright (c) 2010-present Sonatype, Inc.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* Stuart McCulloch (Sonatype, Inc.) - initial API and implementation
*******************************************************************************/
package org.eclipse.sisu.space;
import java.io.IOException;
import java.net.URL;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.List;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;
import java.util.zip.ZipInputStream;
/**
* {@link Iterator} that iterates over named entries inside JAR or ZIP resources.
*/
final class ZipEntryIterator
implements Iterator
{
// ----------------------------------------------------------------------
// Implementation fields
// ----------------------------------------------------------------------
private String[] entryNames;
private int index;
// ----------------------------------------------------------------------
// Constructors
// ----------------------------------------------------------------------
ZipEntryIterator( final URL url )
{
try
{
if ( "file".equals( url.getProtocol() ) )
{
entryNames = getEntryNames( new ZipFile( FileEntryIterator.toFile( url ) ) );
}
else
{
entryNames = getEntryNames( new ZipInputStream( Streams.open( url ) ) );
}
}
catch ( final IOException e )
{
entryNames = new String[0];
}
}
// ----------------------------------------------------------------------
// Public methods
// ----------------------------------------------------------------------
public boolean hasNext()
{
return index < entryNames.length;
}
public String next() // NOSONAR
{
return entryNames[index++];
}
public void remove()
{
throw new UnsupportedOperationException();
}
// ----------------------------------------------------------------------
// Implementation methods
// ----------------------------------------------------------------------
/**
* Returns a string array listing the entries in the given zip file.
*
* @param zipFile The zip file
* @return Array of entry names
*/
private static String[] getEntryNames( final ZipFile zipFile )
throws IOException
{
try
{
final String names[] = new String[zipFile.size()];
final Enumeration e = zipFile.entries(); // NOSONAR
for ( int i = 0; i < names.length; i++ )
{
names[i] = e.nextElement().getName();
}
return names;
}
finally
{
zipFile.close();
}
}
/**
* Returns a string array listing the entries in the given zip stream.
*
* @param zipStream The zip stream
* @return Array of entry names
*/
private static String[] getEntryNames( final ZipInputStream zipStream )
throws IOException
{
try
{
final List names = new ArrayList( 64 );
for ( ZipEntry e = zipStream.getNextEntry(); e != null; e = zipStream.getNextEntry() ) // NOSONAR
{
names.add( e.getName() );
}
return names.toArray( new String[names.size()] );
}
finally
{
zipStream.close();
}
}
}