Java tutorial
/* * Copyright 2009-2016 DigitalGlobe, Inc. * * Licensed 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.mrgeo.hdfs.vector.shp.util; import org.apache.commons.io.FilenameUtils; import java.io.*; import java.math.BigDecimal; import java.text.DecimalFormat; import java.text.NumberFormat; import java.util.ArrayList; import java.util.List; public class FileUtils extends Object { private static NumberFormat formatter = null; public final static int KB = 1024; public final static int SOURCE_DOS = 1; public final static int SOURCE_UNIX = 0; static { formatter = new DecimalFormat("#,###,###"); } /** * For a given shape file name returns a list of it along with all its auxiliary files * @param shapeFilePath path of the shape file to retrieve the files list for * @return an array of all files that belong to the shape file */ public static String[] getShapeFilesList(String shapeFilePath) { if (!FilenameUtils.getExtension(shapeFilePath).equals("shp")) { throw new IllegalArgumentException("Input file must be a shape file."); } List<String> fileNames = new ArrayList<String>(); fileNames.add(shapeFilePath); fileNames.add(shapeFilePath.replaceAll(".shp", ".dbf")); fileNames.add(shapeFilePath.replaceAll(".shp", ".prj")); fileNames.add(shapeFilePath.replaceAll(".shp", ".qpj")); fileNames.add(shapeFilePath.replaceAll(".shp", ".shx")); return fileNames.toArray(new String[] {}); } public static void copyFile(String srcFileName, String dstFileName) throws Exception { // Copies src file to dst file. // If the dst file does not exist, it is created InputStream in = new FileInputStream(srcFileName); OutputStream out = new FileOutputStream(dstFileName); // Transfer bytes from in to out byte[] buf = new byte[1024]; int len; while ((len = in.read(buf)) > 0) { out.write(buf, 0, len); } in.close(); out.close(); } /** * Copies a set of files with a common extension to another location with * optional name variant. * * @param srcFileName * @param dstFileName * @throws Exception */ public static void copyFiles(String srcFileName, String dstFileName, String prefix) throws Exception { copyFilesImpl(srcFileName, dstFileName, prefix, false); } private static void copyFilesImpl(String srcFileName, String dstFileName, String prefix, boolean move) throws Exception { File f = new File(srcFileName); if (!f.exists() || !f.isFile()) throw new Exception("Invalid file! [" + srcFileName + "]"); File dir = f.getParentFile(); String name = f.getName(); int pos = name.indexOf("."); if (pos == -1) { } name = name.substring(0, pos); FilenameFilter filter = new BasenameFilter(name); File[] child = dir.listFiles(filter); File fnew = new File(dstFileName); File dir2 = fnew.getParentFile(); name = fnew.getName(); pos = name.indexOf("."); String newBasename = null; if (pos == -1) { newBasename = name; } else { newBasename = name.substring(0, pos); } for (int i = 0; i < child.length; i++) { name = child[i].getName(); pos = name.indexOf("."); if (pos == -1) { } String ext = name.substring(pos + 1); if (prefix != null) System.out.println( prefix + child[i].getCanonicalPath() + " -> " + dir2 + "\\" + newBasename + "." + ext); copyFile(child[i].getCanonicalPath(), dir2 + "\\" + newBasename + "." + ext); if (move) child[i].delete(); } } public static File createTextFile(String fileName, String raw) throws Exception { if (raw == null) return null; BufferedWriter out = new BufferedWriter(new FileWriter(fileName)); String line = raw; out.write(line); out.newLine(); out.close(); out = null; return new File(fileName); } public static String getLength(long length) { if (length > (KB * KB * KB)) { BigDecimal bd = new BigDecimal(length / (KB * KB * KB)); bd = bd.setScale(1, BigDecimal.ROUND_HALF_EVEN); return formatter.format(bd.doubleValue()) + "GB"; } else if (length > (KB * KB)) { BigDecimal bd = new BigDecimal(length / (KB * KB)); bd = bd.setScale(1, BigDecimal.ROUND_HALF_EVEN); return formatter.format(bd.doubleValue()) + "MB"; } else if (length > (KB)) { BigDecimal bd = new BigDecimal(length / (KB)); bd = bd.setScale(1, BigDecimal.ROUND_HALF_EVEN); return formatter.format(bd.doubleValue()) + "KB"; } else { return formatter.format(length) + "B"; } } public static void insertTextFile(String fileName, BufferedWriter out) throws Exception { try { BufferedReader in = new BufferedReader(new FileReader(fileName)); String str; while ((str = in.readLine()) != null) { out.write(str); out.newLine(); } in.close(); } catch (FileNotFoundException e) { throw new Exception("Insert File [" + fileName + "] not found!"); } catch (Exception e) { throw e; } } public static void moveFiles(String srcFileName, String dstFileName, String prefix) throws Exception { copyFilesImpl(srcFileName, dstFileName, prefix, true); } public static String readTextFile(String fileName) throws Exception { BufferedReader in = new BufferedReader(new FileReader(fileName)); String output = ""; String str = null; String sep = System.getProperty("line.separator"); while ((str = in.readLine()) != null) { output += str + sep; } in.close(); return output; } }