org.apache.hadoop.fs.shell.Test 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.fs.shell;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.LinkedList;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.fs.permission.FsAction;
import org.apache.hadoop.security.AccessControlException;
/**
* Perform shell-like file tests
*/
@InterfaceAudience.Private
@InterfaceStability.Unstable
class Test extends FsCommand {
public static void registerCommands(CommandFactory factory) {
factory.addClass(Test.class, "-test");
}
public static final String NAME = "test";
public static final String USAGE = "-[defswrz] ";
public static final String DESCRIPTION =
"Answer various questions about , with result via exit status.\n"
+ " -d return 0 if is a directory.\n"
+ " -e return 0 if exists.\n"
+ " -f return 0 if is a file.\n"
+ " -s return 0 if file is greater "
+ " than zero bytes in size.\n"
+ " -w return 0 if file exists "
+ " and write permission is granted.\n"
+ " -r return 0 if file exists "
+ " and read permission is granted.\n"
+ " -z return 0 if file is "
+ " zero bytes in size, else return 1.";
private char flag;
@Override
protected void processOptions(LinkedList args) {
CommandFormat cf = new CommandFormat(1, 1,
"e", "d", "f", "s", "z", "w", "r");
cf.parse(args);
String[] opts = cf.getOpts().toArray(new String[0]);
switch (opts.length) {
case 0:
throw new IllegalArgumentException("No test flag given");
case 1:
flag = opts[0].charAt(0);
break;
default:
throw new IllegalArgumentException("Only one test flag is allowed");
}
}
@Override
protected void processPath(PathData item) throws IOException {
boolean test = false;
switch (flag) {
case 'e':
test = true;
break;
case 'd':
test = item.stat.isDirectory();
break;
case 'f':
test = item.stat.isFile();
break;
case 's':
test = (item.stat.getLen() > 0);
break;
case 'z':
test = (item.stat.getLen() == 0);
break;
case 'w':
test = testAccess(item, FsAction.WRITE);
break;
case 'r':
test = testAccess(item, FsAction.READ);
break;
default:
break;
}
if (!test) {
exitCode = 1;
}
}
private boolean testAccess(PathData item, FsAction action)
throws IOException {
try {
item.fs.access(item.path, action);
return true;
} catch (AccessControlException | FileNotFoundException e) {
return false;
}
}
@Override
protected void processNonexistentPath(PathData item) throws IOException {
exitCode = 1;
}
}