Java tutorial
/** * 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.oozie.util; import org.apache.hadoop.fs.FileSystem; import org.apache.hadoop.fs.Path; import java.io.IOException; import java.net.URI; public final class FSUtils { public static final String FILE_SCHEME_PREFIX = "file:"; public static Path getSymLinkTarget(FileSystem fs, Path p) throws IOException { try { //getSymlink doesn't work with fragment name, need to remove fragment before calling getSymlink Path tempPath = new URI(p.toString()).getFragment() == null ? p : new Path(new URI(p.toString()).getPath()); return fs.getFileLinkStatus(tempPath).getSymlink(); } catch (java.net.URISyntaxException e) { throw new IOException(e); } } public static boolean isSymlink(FileSystem fs, Path p) throws IOException { try { //isSymlink doesn't work with fragment name, need to remove fragment before checking for symlink Path tempPath = new URI(p.toString()).getFragment() == null ? p : new Path(new URI(p.toString()).getPath()); return fs.getFileLinkStatus(tempPath).isSymlink(); } catch (java.net.URISyntaxException e) { throw new IOException(e); } } public static void createSymlink(FileSystem fs, Path target, Path link, boolean createParent) throws IOException { fs.createSymlink(target, link, createParent); } public static boolean isLocalFile(String fileName) { return fileName.startsWith(FILE_SCHEME_PREFIX + "/"); } public static boolean isLocalFile(Path filePath) { return isLocalFile(filePath.toString()); } public static boolean isNotLocalFile(String fileName) { return !isLocalFile(fileName); } }