Java tutorial
/******************************************************************************* * Copyright 2015-2016 - CNRS (Centre National de Recherche Scientifique) * * 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 eu.project.ttc.utils; import java.io.BufferedReader; import java.io.File; import java.io.FileNotFoundException; import java.io.FileReader; import java.io.IOException; import java.nio.charset.Charset; import java.nio.file.Files; import java.nio.file.Paths; import java.util.List; import java.util.jar.JarEntry; import java.util.jar.JarFile; import com.google.common.base.Preconditions; import com.google.common.base.Splitter; import com.google.common.collect.Iterables; import com.google.common.collect.Lists; public class FileUtils { public static String getFileName(String path) { return Iterables.getLast(Splitter.on('/').split(path)); } public static String humanReadableByteCount(long bytes, boolean si) { int unit = si ? 1000 : 1024; if (bytes < unit) return bytes + " B"; int exp = (int) (Math.log(bytes) / Math.log(unit)); String pre = (si ? "kMGTPE" : "KMGTPE").charAt(exp - 1) + (si ? "" : "i"); return String.format("%.1f %sB", bytes / Math.pow(unit, exp), pre); } public static boolean isJar(String file) { try { JarFile jar = new JarFile(file); JarEntry entry = jar.getJarEntry("META-INF/MANIFEST.MF"); jar.close(); return entry != null; } catch (IOException e) { return false; } } public static List<String> getUncommentedLines(File file, Charset forName) throws IOException { try { List<String> ids = Lists.newArrayList(); try (BufferedReader br = new BufferedReader(new FileReader(file))) { for (String line; (line = br.readLine()) != null;) { if (!line.trim().startsWith("#") && !line.trim().isEmpty()) ids.add(line.trim()); } } return ids; } catch (FileNotFoundException e) { throw new IOException(e); } } public static String replaceRootDir(String fileUri, File oldRoot, File newRoot) throws IOException { Preconditions.checkArgument(oldRoot.isDirectory()); String oldRootPath = oldRoot.getCanonicalPath(); Preconditions.checkArgument(fileUri.startsWith(oldRootPath), "file path %s must start with the old root path %s", fileUri, oldRoot); String newRootPath = newRoot.getCanonicalPath(); return replaceRootDir(fileUri, oldRootPath, newRootPath); } public static String replaceRootDir(String fileUri, String oldRootPath, String newRootPath) { Preconditions.checkArgument(fileUri.startsWith(oldRootPath), "file path %s must start with the old root path %s", fileUri, oldRootPath); return fileUri.replaceFirst(oldRootPath, newRootPath); } public static String readFile(String path, Charset encoding) throws IOException { byte[] encoded = Files.readAllBytes(Paths.get(path)); return new String(encoded, encoding); } public static String replaceExtensionWith(String toFilePath, String newExtension) { String dirname = toFilePath.substring(0, toFilePath.lastIndexOf(File.separatorChar) + 1); String filename = toFilePath.substring(toFilePath.lastIndexOf(File.separatorChar) + 1, toFilePath.length()); String basename = filename.contains(".") ? filename.substring(0, filename.lastIndexOf('.') + 1) : (filename + "."); return Paths.get(dirname, basename + newExtension).toString(); } }