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/**
* 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.protocol;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.permission.FsPermission;
import org.apache.hadoop.hdfs.DFSUtil;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.Writable;
import org.apache.hadoop.io.WritableFactories;
import org.apache.hadoop.io.WritableFactory;
import org.apache.avro.reflect.Nullable;
/** Interface that represents the over the wire information for a file.
*/
@InterfaceAudience.Private
@InterfaceStability.Evolving
public class HdfsFileStatus implements Writable {
static { // register a ctor
WritableFactories.setFactory
(HdfsFileStatus.class,
new WritableFactory() {
public Writable newInstance() { return new HdfsFileStatus(); }
});
}
private byte[] path; // local name of the inode that's encoded in java UTF8
@Nullable
private byte[] symlink; // symlink target encoded in java UTF8 or null
private long length;
private boolean isdir;
private short block_replication;
private long blocksize;
private long modification_time;
private long access_time;
private FsPermission permission;
private String owner;
private String group;
public static final byte[] EMPTY_NAME = new byte[0];
/**
* default constructor
*/
public HdfsFileStatus() {
this(0, false, 0, 0, 0, 0, null, null, null, null, null);
}
/**
* Constructor
* @param length the number of bytes the file has
* @param isdir if the path is a directory
* @param block_replication the replication factor
* @param blocksize the block size
* @param modification_time modification time
* @param access_time access time
* @param permission permission
* @param owner the owner of the path
* @param group the group of the path
* @param path the local name in java UTF8 encoding the same as that in-memory
*/
public HdfsFileStatus(long length, boolean isdir, int block_replication,
long blocksize, long modification_time, long access_time,
FsPermission permission, String owner, String group,
byte[] symlink, byte[] path) {
this.length = length;
this.isdir = isdir;
this.block_replication = (short)block_replication;
this.blocksize = blocksize;
this.modification_time = modification_time;
this.access_time = access_time;
this.permission = (permission == null) ?
FsPermission.getDefault() : permission;
this.owner = (owner == null) ? "" : owner;
this.group = (group == null) ? "" : group;
this.symlink = symlink;
this.path = path;
}
/**
* Get the length of this file, in bytes.
* @return the length of this file, in bytes.
*/
final public long getLen() {
return length;
}
/**
* Is this a directory?
* @return true if this is a directory
*/
final public boolean isDir() {
return isdir;
}
/**
* Is this a symbolic link?
* @return true if this is a symbolic link
*/
public boolean isSymlink() {
return symlink != null;
}
/**
* Get the block size of the file.
* @return the number of bytes
*/
final public long getBlockSize() {
return blocksize;
}
/**
* Get the replication factor of a file.
* @return the replication factor of a file.
*/
final public short getReplication() {
return block_replication;
}
/**
* Get the modification time of the file.
* @return the modification time of file in milliseconds since January 1, 1970 UTC.
*/
final public long getModificationTime() {
return modification_time;
}
/**
* Get the access time of the file.
* @return the access time of file in milliseconds since January 1, 1970 UTC.
*/
final public long getAccessTime() {
return access_time;
}
/**
* Get FsPermission associated with the file.
* @return permssion
*/
final public FsPermission getPermission() {
return permission;
}
/**
* Get the owner of the file.
* @return owner of the file
*/
final public String getOwner() {
return owner;
}
/**
* Get the group associated with the file.
* @return group for the file.
*/
final public String getGroup() {
return group;
}
/**
* Check if the local name is empty
* @return true if the name is empty
*/
final public boolean isEmptyLocalName() {
return path.length == 0;
}
/**
* Get the string representation of the local name
* @return the local name in string
*/
final public String getLocalName() {
return DFSUtil.bytes2String(path);
}
/**
* Get the Java UTF8 representation of the local name
* @return the local name in java UTF8
*/
final public byte[] getLocalNameInBytes() {
return path;
}
/**
* Get the string representation of the full path name
* @param parent the parent path
* @return the full path in string
*/
final public String getFullName(final String parent) {
if (isEmptyLocalName()) {
return parent;
}
StringBuilder fullName = new StringBuilder(parent);
if (!parent.endsWith(Path.SEPARATOR)) {
fullName.append(Path.SEPARATOR);
}
fullName.append(getLocalName());
return fullName.toString();
}
/**
* Get the full path
* @param parent the parent path
* @return the full path
*/
final public Path getFullPath(final Path parent) {
if (isEmptyLocalName()) {
return parent;
}
return new Path(parent, getLocalName());
}
/**
* Get the string representation of the symlink.
* @return the symlink as a string.
*/
final public String getSymlink() {
return DFSUtil.bytes2String(symlink);
}
//////////////////////////////////////////////////
// Writable
//////////////////////////////////////////////////
public void write(DataOutput out) throws IOException {
out.writeInt(path.length);
out.write(path);
out.writeLong(length);
out.writeBoolean(isdir);
out.writeShort(block_replication);
out.writeLong(blocksize);
out.writeLong(modification_time);
out.writeLong(access_time);
permission.write(out);
Text.writeString(out, owner);
Text.writeString(out, group);
out.writeBoolean(isSymlink());
if (isSymlink()) {
out.writeInt(symlink.length);
out.write(symlink);
}
}
public void readFields(DataInput in) throws IOException {
int numOfBytes = in.readInt();
if (numOfBytes == 0) {
this.path = EMPTY_NAME;
} else {
this.path = new byte[numOfBytes];
in.readFully(path);
}
this.length = in.readLong();
this.isdir = in.readBoolean();
this.block_replication = in.readShort();
blocksize = in.readLong();
modification_time = in.readLong();
access_time = in.readLong();
permission.readFields(in);
owner = Text.readString(in);
group = Text.readString(in);
if (in.readBoolean()) {
numOfBytes = in.readInt();
this.symlink = new byte[numOfBytes];
in.readFully(symlink);
}
}
}