/*
* 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 com.frostwire.jlibtorrent;
import java.io.*;
public final class Utils {
private Utils() {
}
/**
* The extension separator character.
*
* @since 1.4
*/
public static final char EXTENSION_SEPARATOR = '.';
/**
* The Unix separator character.
*/
private static final char UNIX_SEPARATOR = '/';
/**
* The Windows separator character.
*/
private static final char WINDOWS_SEPARATOR = '\\';
private static final int EOF = -1;
/**
* Gets the name minus the path from a full filename.
* <p/>
* This method will handle a file in either Unix or Windows format.
* The text after the last forward or backslash is returned.
* <pre>
* a/b/c.txt --> c.txt
* a.txt --> a.txt
* a/b/c --> c
* a/b/c/ --> ""
* </pre>
* <p/>
* The output will be the same irrespective of the machine that the code is running on.
*
* @param filename the filename to query, null returns null
* @return the name of the file without the path, or an empty string if none exists
*/
public static String getName(String filename) {
if (filename == null) {
return null;
}
int index = indexOfLastSeparator(filename);
return filename.substring(index + 1);
}
/**
* Gets the base name, minus the full path and extension, from a full filename.
* <p/>
* This method will handle a file in either Unix or Windows format.
* The text after the last forward or backslash and before the last dot is returned.
* <pre>
* a/b/c.txt --> c
* a.txt --> a
* a/b/c --> c
* a/b/c/ --> ""
* </pre>
* <p/>
* The output will be the same irrespective of the machine that the code is running on.
*
* @param filename the filename to query, null returns null
* @return the name of the file without the path, or an empty string if none exists
*/
public static String getBaseName(String filename) {
return removeExtension(getName(filename));
}
//-----------------------------------------------------------------------
/**
* Removes the extension from a filename.
* <p/>
* This method returns the textual part of the filename before the last dot.
* There must be no directory separator after the dot.
* <pre>
* foo.txt --> foo
* a\b\c.jpg --> a\b\c
* a\b\c --> a\b\c
* a.b\c --> a.b\c
* </pre>
* <p/>
* The output will be the same irrespective of the machine that the code is running on.
*
* @param filename the filename to query, null returns null
* @return the filename minus the extension
*/
public static String removeExtension(String filename) {
if (filename == null) {
return null;
}
int index = indexOfExtension(filename);
if (index == -1) {
return filename;
} else {
return filename.substring(0, index);
}
}
/**
* Returns the index of the last extension separator character, which is a dot.
* <p/>
* This method also checks that there is no directory separator after the last dot.
* To do this it uses {@link #indexOfLastSeparator(String)} which will
* handle a file in either Unix or Windows format.
* <p/>
* The output will be the same irrespective of the machine that the code is running on.
*
* @param filename the filename to find the last path separator in, null returns -1
* @return the index of the last separator character, or -1 if there
* is no such character
*/
public static int indexOfExtension(String filename) {
if (filename == null) {
return -1;
}
int extensionPos = filename.lastIndexOf(EXTENSION_SEPARATOR);
int lastSeparator = indexOfLastSeparator(filename);
return lastSeparator > extensionPos ? -1 : extensionPos;
}
/**
* Returns the index of the last directory separator character.
* <p/>
* This method will handle a file in either Unix or Windows format.
* The position of the last forward or backslash is returned.
* <p/>
* The output will be the same irrespective of the machine that the code is running on.
*
* @param filename the filename to find the last path separator in, null returns -1
* @return the index of the last separator character, or -1 if there
* is no such character
*/
public static int indexOfLastSeparator(String filename) {
if (filename == null) {
return -1;
}
int lastUnixPos = filename.lastIndexOf(UNIX_SEPARATOR);
int lastWindowsPos = filename.lastIndexOf(WINDOWS_SEPARATOR);
return Math.max(lastUnixPos, lastWindowsPos);
}
/**
* Get the contents of an <code>InputStream</code> as a <code>byte[]</code>.
* Use this method instead of <code>toByteArray(InputStream)</code>
* when <code>InputStream</code> size is known
*
* @param input the <code>InputStream</code> to read from
* @param size the size of <code>InputStream</code>
* @return the requested byte array
* @throws java.io.IOException if an I/O error occurs or <code>InputStream</code> size differ from parameter size
* @throws IllegalArgumentException if size is less than zero
* @since 2.1
*/
public static byte[] toByteArray(InputStream input, int size) throws IOException {
if (size < 0) {
throw new IllegalArgumentException("Size must be equal or greater than zero: " + size);
}
if (size == 0) {
return new byte[0];
}
byte[] data = new byte[size];
int offset = 0;
int readed;
while (offset < size && (readed = input.read(data, offset, size - offset)) != EOF) {
offset += readed;
}
if (offset != size) {
throw new IOException("Unexpected readed size. current: " + offset + ", excepted: " + size);
}
return data;
}
/**
* Get contents of an <code>InputStream</code> as a <code>byte[]</code>.
* Use this method instead of <code>toByteArray(InputStream)</code>
* when <code>InputStream</code> size is known.
* <b>NOTE:</b> the method checks that the length can safely be cast to an int without truncation
* before using {@link Utils#toByteArray(java.io.InputStream, int)} to read into the byte array.
* (Arrays can have no more than Integer.MAX_VALUE entries anyway)
*
* @param input the <code>InputStream</code> to read from
* @param size the size of <code>InputStream</code>
* @return the requested byte array
* @throws IOException if an I/O error occurs or <code>InputStream</code> size differ from parameter size
* @throws IllegalArgumentException if size is less than zero or size is greater than Integer.MAX_VALUE
* @see Utils#toByteArray(java.io.InputStream, int)
* @since 2.1
*/
public static byte[] toByteArray(InputStream input, long size) throws IOException {
if (size > Integer.MAX_VALUE) {
throw new IllegalArgumentException("Size cannot be greater than Integer max value: " + size);
}
return toByteArray(input, (int) size);
}
/**
* Unconditionally close a <code>Closeable</code>.
* <p/>
* Equivalent to {@link java.io.Closeable#close()}, except any exceptions will be ignored.
* This is typically used in finally blocks.
* <p/>
* Example code:
* <pre>
* Closeable closeable = null;
* try {
* closeable = new FileReader("foo.txt");
* // process closeable
* closeable.close();
* } catch (Exception e) {
* // error handling
* } finally {
* IOUtils.closeQuietly(closeable);
* }
* </pre>
*
* @param closeable the object to close, may be null or already closed
* @since 2.0
*/
public static void closeQuietly(Closeable closeable) {
try {
if (closeable != null) {
closeable.close();
}
} catch (IOException ioe) {
// ignore
}
}
/**
* Unconditionally close an <code>InputStream</code>.
* <p/>
* Equivalent to {@link InputStream#close()}, except any exceptions will be ignored.
* This is typically used in finally blocks.
* <p/>
* Example code:
* <pre>
* byte[] data = new byte[1024];
* InputStream in = null;
* try {
* in = new FileInputStream("foo.txt");
* in.read(data);
* in.close(); //close errors are handled
* } catch (Exception e) {
* // error handling
* } finally {
* IOUtils.closeQuietly(in);
* }
* </pre>
*
* @param input the InputStream to close, may be null or already closed
*/
public static void closeQuietly(InputStream input) {
closeQuietly((Closeable) input);
}
//-----------------------------------------------------------------------
/**
* Opens a {@link java.io.FileInputStream} for the specified file, providing better
* error messages than simply calling <code>new FileInputStream(file)</code>.
* <p/>
* At the end of the method either the stream will be successfully opened,
* or an exception will have been thrown.
* <p/>
* An exception is thrown if the file does not exist.
* An exception is thrown if the file object exists but is a directory.
* An exception is thrown if the file exists but cannot be read.
*
* @param file the file to open for input, must not be {@code null}
* @return a new {@link java.io.FileInputStream} for the specified file
* @throws java.io.FileNotFoundException if the file does not exist
* @throws IOException if the file object is a directory
* @throws IOException if the file cannot be read
* @since 1.3
*/
public static FileInputStream openInputStream(File file) throws IOException {
if (file.exists()) {
if (file.isDirectory()) {
throw new IOException("File '" + file + "' exists but is a directory");
}
if (file.canRead() == false) {
throw new IOException("File '" + file + "' cannot be read");
}
} else {
throw new FileNotFoundException("File '" + file + "' does not exist");
}
return new FileInputStream(file);
}
/**
* Reads the contents of a file into a byte array.
* The file is always closed.
*
* @param file the file to read, must not be {@code null}
* @return the file contents, never {@code null}
* @throws IOException in case of an I/O error
* @since 1.1
*/
public static byte[] readFileToByteArray(File file) throws IOException {
InputStream in = null;
try {
in = openInputStream(file);
return toByteArray(in, file.length());
} finally {
closeQuietly(in);
}
}
/**
* Writes a byte array to a file creating the file if it does not exist.
* <p>
* NOTE: As from v1.3, the parent directories of the file will be created
* if they do not exist.
*
* @param file the file to write to
* @param data the content to write to the file
* @throws IOException in case of an I/O error
* @since 1.1
*/
public static void writeByteArrayToFile(File file, byte[] data) throws IOException {
writeByteArrayToFile(file, data, false);
}
/**
* Writes a byte array to a file creating the file if it does not exist.
*
* @param file the file to write to
* @param data the content to write to the file
* @param append if {@code true}, then bytes will be added to the
* end of the file rather than overwriting
* @throws IOException in case of an I/O error
* @since IO 2.1
*/
public static void writeByteArrayToFile(File file, byte[] data, boolean append) throws IOException {
OutputStream out = null;
try {
out = openOutputStream(file, append);
out.write(data);
out.close(); // don't swallow close Exception if copy completes normally
} finally {
closeQuietly(out);
}
}
//-----------------------------------------------------------------------
/**
* Opens a {@link FileOutputStream} for the specified file, checking and
* creating the parent directory if it does not exist.
* <p>
* At the end of the method either the stream will be successfully opened,
* or an exception will have been thrown.
* <p>
* The parent directory will be created if it does not exist.
* The file will be created if it does not exist.
* An exception is thrown if the file object exists but is a directory.
* An exception is thrown if the file exists but cannot be written to.
* An exception is thrown if the parent directory cannot be created.
*
* @param file the file to open for output, must not be {@code null}
* @return a new {@link FileOutputStream} for the specified file
* @throws IOException if the file object is a directory
* @throws IOException if the file cannot be written to
* @throws IOException if a parent directory needs creating but that fails
* @since 1.3
*/
public static FileOutputStream openOutputStream(File file) throws IOException {
return openOutputStream(file, false);
}
/**
* Opens a {@link FileOutputStream} for the specified file, checking and
* creating the parent directory if it does not exist.
* <p>
* At the end of the method either the stream will be successfully opened,
* or an exception will have been thrown.
* <p>
* The parent directory will be created if it does not exist.
* The file will be created if it does not exist.
* An exception is thrown if the file object exists but is a directory.
* An exception is thrown if the file exists but cannot be written to.
* An exception is thrown if the parent directory cannot be created.
*
* @param file the file to open for output, must not be {@code null}
* @param append if {@code true}, then bytes will be added to the
* end of the file rather than overwriting
* @return a new {@link FileOutputStream} for the specified file
* @throws IOException if the file object is a directory
* @throws IOException if the file cannot be written to
* @throws IOException if a parent directory needs creating but that fails
* @since 2.1
*/
public static FileOutputStream openOutputStream(File file, boolean append) throws IOException {
if (file.exists()) {
if (file.isDirectory()) {
throw new IOException("File '" + file + "' exists but is a directory");
}
if (file.canWrite() == false) {
throw new IOException("File '" + file + "' cannot be written to");
}
} else {
File parent = file.getParentFile();
if (parent != null) {
if (!parent.mkdirs() && !parent.isDirectory()) {
throw new IOException("Directory '" + parent + "' could not be created");
}
}
}
return new FileOutputStream(file, append);
}
}