Java tutorial
/* * Copyright 2012 The SCAPE Project Consortium. * * 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. * under the License. */ package eu.scape_project.archiventory.utils; import java.io.*; import org.apache.commons.lang.RandomStringUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * I/O Utils * * @author Sven Schlarb https://github.com/shsdev * @version 0.1 */ public class IOUtils { private static Logger logger = LoggerFactory.getLogger(IOUtils.class.getName()); /** * Copy input stream to temporary file * * @param is Input sream * @param prefix Prefix of temporary file * @param ext Extension of temporary file * @return Temporary file */ public static File copyInputStreamToTempFile(InputStream is, String prefix, String ext) { FileOutputStream fos = null; File tmpFile = null; try { tmpFile = File.createTempFile(prefix, ext); fos = new FileOutputStream(tmpFile); org.apache.commons.io.IOUtils.copy(is, fos); fos.flush(); } catch (FileNotFoundException ex) { logger.error("Temporary file not available.", ex); } catch (IOException ex) { logger.error("I/O Error occured.", ex); } finally { if (is != null) { try { is.close(); } catch (IOException _) { // ignore } } if (fos != null) { try { fos.close(); } catch (IOException _) { // ignore } } return tmpFile; } } /** * Copy byte array to file in temporary directory * * @param barray byte array * @param dir Directory where the temporary file is created * @param ext Extension of temporary file * @return Temporary file */ public static File copyByteArrayToTempFileInDir(byte[] barray, String dir, String ext) { String filename = System.currentTimeMillis() + RandomStringUtils.randomAlphabetic(5) + ext; if (!dir.endsWith("/")) { dir += "/"; } FileOutputStream fos = null; File tmpFile = null; try { tmpFile = new File(dir + filename); fos = new FileOutputStream(tmpFile); org.apache.commons.io.IOUtils.write(barray, fos); fos.flush(); fos.close(); } catch (FileNotFoundException ex) { logger.error("Temporary file not available.", ex); } catch (IOException ex) { logger.error("I/O Error", ex); } finally { if (fos != null) { try { fos.close(); } catch (IOException _) { // ignore } } } return tmpFile; } /** * Copy byte array to temporary file * * @param barray byte array * @param prefix Prefix of temporary file * @param ext Extension of temporary file * @return Temporary file */ public static File copyByteArrayToTempFile(byte[] barray, String prefix, String ext) { FileOutputStream fos = null; File tmpFile = null; try { tmpFile = File.createTempFile(prefix, ext); fos = new FileOutputStream(tmpFile); org.apache.commons.io.IOUtils.write(barray, fos); fos.flush(); fos.close(); } catch (FileNotFoundException ex) { logger.error("Temporary file not available.", ex); } catch (IOException ex) { logger.error("I/O Error", ex); } finally { if (fos != null) { try { fos.close(); } catch (IOException _) { // ignore } } } return tmpFile; } public static String copyInputStreamToString(InputStream is) { String strContent = null; try { strContent = org.apache.commons.io.IOUtils.toString(is); } catch (IOException ex) { logger.error("I/O Error", ex); } finally { if (is != null) { try { is.close(); } catch (IOException _) { // ignore } } } return strContent; } public static byte[] getBytesFromFile(String filePath) throws IOException { File file = new File(filePath); if (!file.exists()) { throw new FileNotFoundException("File not available"); } InputStream is = null; byte[] bytes = null; try { is = new FileInputStream(file); long length = file.length(); if (length > Integer.MAX_VALUE) { throw new IllegalArgumentException("File object is too large"); } bytes = new byte[(int) length]; int offset = 0; int numRead = 0; while (offset < bytes.length && (numRead = is.read(bytes, offset, bytes.length - offset)) >= 0) { offset += numRead; } } catch (IOException ex) { logger.error("I/O Error", ex); } finally { if (is != null) { try { is.close(); } catch (IOException _) { // ignore } } } return bytes; } }