org.openjdk.jmh.util.FileUtils Maven / Gradle / Ivy
/*
* Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package org.openjdk.jmh.util;
import java.io.*;
import java.nio.channels.Channel;
import java.util.ArrayList;
import java.util.Collection;
import java.util.LinkedList;
import java.util.List;
/**
* A utility class for File creation and manipulation.
*/
public class FileUtils {
// Static access only
private FileUtils() {
}
public static File tempFile(String suffix) throws IOException {
File file = File.createTempFile("jmh", suffix);
file.deleteOnExit();
return file;
}
/**
* Helper method for extracting a given resource to File
*
* @param name name of the resource
* @return a File pointing to the extracted resource
* @throws IOException if things go crazy
*/
public static File extractFromResource(String name) throws IOException {
InputStream fis = null;
OutputStream fos = null;
try {
File temp = FileUtils.tempFile("extracted");
fis = FileUtils.class.getResourceAsStream(name);
fos = new FileOutputStream(temp);
byte[] buf = new byte[8192];
int read;
while ((read = fis.read(buf)) != -1) {
fos.write(buf, 0, read);
}
fos.close();
return temp;
} finally {
FileUtils.safelyClose(fis);
FileUtils.safelyClose(fos);
}
}
/**
* Create a temporary file (see {@link File#createTempFile(String, String)}) and fill it with the given lines.
*
* @param suffix file suffix {@link File#createTempFile(String, String)}
* @param lines to be written
*
* @return the temporary file absolute path
* @throws IOException on file creation error
*/
public static String createTempFileWithLines(String suffix, Iterable lines)
throws IOException {
File file = FileUtils.tempFile(suffix);
PrintWriter pw = new PrintWriter(file);
for (String l : lines) {
pw.println(l);
}
pw.close();
return file.getAbsolutePath();
}
public static Collection tail(File file, int num) throws IOException {
FileInputStream fis = null;
try {
fis = new FileInputStream(file);
BufferedReader reader = new BufferedReader(new InputStreamReader(fis));
LinkedList lines = new LinkedList();
String line;
while ((line = reader.readLine()) != null) {
lines.add(line);
if (lines.size() > num) {
lines.remove(0);
}
}
return lines;
} finally {
FileUtils.safelyClose(fis);
}
}
public static Collection readAllLines(Reader src) throws IOException {
BufferedReader reader = new BufferedReader(src);
List lines = new ArrayList();
String line;
while ((line = reader.readLine()) != null) {
lines.add(line);
}
return lines;
}
public static Collection readAllLines(File file) throws IOException {
FileReader fr = null;
try {
fr = new FileReader(file);
return readAllLines(fr);
} finally {
FileUtils.safelyClose(fr);
}
}
public static Collection getClasses(File root) {
Collection result = new ArrayList();
List newDirs = new ArrayList();
newDirs.add(root);
while (!newDirs.isEmpty()) {
List add = new ArrayList();
for (File dir : newDirs) {
File[] files = dir.listFiles();
if (files != null) {
for (File f : files) {
if (f.isDirectory()) {
add.add(f);
} else {
if (f.getName().endsWith(".class")) {
result.add(f);
}
}
}
}
}
newDirs.clear();
newDirs = add;
}
return result;
}
public static void copy(String src, String dst) throws IOException {
FileInputStream fis = null;
FileOutputStream fos = null;
try {
fis = new FileInputStream(src);
fos = new FileOutputStream(dst);
byte[] buf = new byte[8192];
int read;
while ((read = fis.read(buf)) != -1) {
fos.write(buf, 0, read);
}
fos.close();
} finally {
FileUtils.safelyClose(fis);
FileUtils.safelyClose(fos);
}
}
public static void safelyClose(OutputStream out) {
if (out != null) {
try {
out.flush();
} catch (IOException e) {
// ignore
}
try {
out.close();
} catch (IOException e) {
// ignore
}
}
}
public static void safelyClose(InputStream in) {
if (in != null) {
try {
in.close();
} catch (IOException e) {
// ignore
}
}
}
public static void safelyClose(Channel channel) {
if (channel != null) {
try {
channel.close();
} catch (IOException e) {
// do nothing
}
}
}
public static void safelyClose(Reader reader) {
if (reader != null) {
try {
reader.close();
} catch (IOException e) {
// do nothing
}
}
}
public static void touch(String f) throws IOException {
File file = new File(f);
try {
if (file.createNewFile() || file.canWrite()) {
return;
}
} catch (IOException e) {
// fall-through
}
throw new IOException("The file is not writable: " + f);
}
}