org.apache.hadoop.hdfs.server.namenode.XAttrFeature Maven / Gradle / Ivy
/**
* 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.hadoop.hdfs.server.namenode;
import java.util.ArrayList;
import java.util.List;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.fs.XAttr;
import org.apache.hadoop.hdfs.XAttrHelper;
import com.google.common.collect.ImmutableList;
/**
* Feature for extended attributes.
*/
@InterfaceAudience.Private
public class XAttrFeature implements INode.Feature {
static final int PACK_THRESHOLD = 1024;
/** The packed bytes for small size XAttrs. */
private byte[] attrs;
/**
* List to store large size XAttrs.
* Typically XAttr value size is small, so this
* list is null usually.
*/
private ImmutableList xAttrs;
public XAttrFeature(List xAttrs) {
if (xAttrs != null && !xAttrs.isEmpty()) {
List toPack = new ArrayList();
ImmutableList.Builder b = null;
for (XAttr attr : xAttrs) {
if (attr.getValue() == null ||
attr.getValue().length <= PACK_THRESHOLD) {
toPack.add(attr);
} else {
if (b == null) {
b = ImmutableList.builder();
}
b.add(attr);
}
}
this.attrs = XAttrFormat.toBytes(toPack);
if (b != null) {
this.xAttrs = b.build();
}
}
}
/**
* Get the XAttrs.
* @return the XAttrs
*/
public List getXAttrs() {
if (xAttrs == null) {
return XAttrFormat.toXAttrs(attrs);
} else {
if (attrs == null) {
return xAttrs;
} else {
List result = new ArrayList<>();
result.addAll(XAttrFormat.toXAttrs(attrs));
result.addAll(xAttrs);
return result;
}
}
}
/**
* Get XAttr by name with prefix.
* @param prefixedName xAttr name with prefix
* @return the XAttr
*/
public XAttr getXAttr(String prefixedName) {
XAttr attr = XAttrFormat.getXAttr(attrs, prefixedName);
if (attr == null && xAttrs != null) {
XAttr toFind = XAttrHelper.buildXAttr(prefixedName);
for (XAttr a : xAttrs) {
if (a.equalsIgnoreValue(toFind)) {
attr = a;
break;
}
}
}
return attr;
}
}