/*
* Copyright 2013 Red Hat, Inc. and/or its affiliates.
*
* Licensed under the Eclipse Public License version 1.0, available at
* http://www.eclipse.org/legal/epl-v10.html
*/
package org.jboss.forge.addon.resource.util;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.security.DigestInputStream;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import org.jboss.forge.addon.resource.DirectoryResource;
import org.jboss.forge.addon.resource.Resource;
import org.jboss.forge.addon.resource.ResourceFilter;
import org.jboss.forge.furnace.util.Assert;
/**
* A set of utilities to work with the resources API.
*
* @author Mike Brock
* @author <a href="mailto:lincolnbaxter@gmail.com">Lincoln Baxter, III</a>
* @author Vineet Reynolds
*/
public class ResourceUtil
{
/**
* Returns the {@link Byte} array message digest of {@link #getResourceInputStream()} using the default MD5
* {@link MessageDigest}.
*/
public static byte[] getDigest(Resource<?> resource)
{
try
{
return getDigest(resource, MessageDigest.getInstance("MD5"));
}
catch (NoSuchAlgorithmException e)
{
throw new IllegalStateException("Error calculating digest for resource [" + resource.getFullyQualifiedName()
+ "]", e);
}
}
/**
* Returns the {@link Byte} array message digest of {@link #getResourceInputStream()} using the given
* {@link MessageDigest}.
*/
public static byte[] getDigest(Resource<?> resource, MessageDigest digest)
{
try (InputStream stream = resource.getResourceInputStream();
DigestInputStream digestStream = new DigestInputStream(stream, digest))
{
byte[] buffer = new byte[16384];
while (digestStream.read(buffer, 0, buffer.length) != -1)
{
}
}
catch (IOException e)
{
throw new IllegalStateException("Error calculating digest for resource [" + resource.getFullyQualifiedName()
+ "]", e);
}
return digest.digest();
}
/**
* A simple utility method to locate the outermost contextual File reference for the specified resource.
*
* @param r resource instance.
* @return outermost relevant file context.
*/
public static File getContextFile(Resource<?> r)
{
do
{
Object o = r.getUnderlyingResourceObject();
if (o instanceof File)
{
return (File) r.getUnderlyingResourceObject();
}
}
while ((r = r.getParent()) != null);
return null;
}
public static DirectoryResource getContextDirectory(final Resource<?> r)
{
Resource<?> temp = r;
do
{
if (temp instanceof DirectoryResource)
{
return (DirectoryResource) temp;
}
}
while ((temp != null) && ((temp = temp.getParent()) != null));
return null;
}
public static boolean isChildOf(final Resource<?> parent, final Resource<?> isChild)
{
Resource<?> r = isChild;
while ((r = r.getParent()) != null)
{
if (r.equals(parent))
{
return true;
}
}
return false;
}
@SuppressWarnings("unchecked")
public static <E extends Resource<?>, R extends Collection<E>> R filter(ResourceFilter filter, Collection<E> list)
{
List<E> result = new ArrayList<>();
for (E resource : list)
{
if (filter.accept(resource))
{
result.add(resource);
}
}
return (R) result;
}
@SuppressWarnings("unchecked")
public static <E extends Resource<?>, R extends Collection<E>, I extends Collection<Resource<?>>> R filterByType(
final Class<E> type, final I list)
{
ResourceFilter filter = new ResourceFilter()
{
@Override
public boolean accept(Resource<?> resource)
{
return type.isAssignableFrom(resource.getClass());
}
};
return (R) filter(filter, list);
}
public static boolean isParentOf(Resource<?> parent, Resource<?> child)
{
Assert.notNull(parent, "Parent resource must not be null.");
Assert.notNull(child, "Child resource must not be null.");
while (child.getParent() != null)
{
if (parent == child.getParent() || parent.equals(child.getParent()))
return true;
child = child.getParent();
}
return false;
}
}