net.derquinse.common.io.DurableFiles Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of derquinse-common-base Show documentation
Show all versions of derquinse-common-base Show documentation
Module containing support classes depending on Java SE 6, Guava 11 and Joda-Time 2.0
/*
* Copyright (C) the original author or authors.
*
* 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 net.derquinse.common.io;
import java.io.Closeable;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStreamWriter;
import java.nio.charset.Charset;
import net.derquinse.common.base.NotInstantiable;
import com.google.common.annotations.Beta;
import com.google.common.io.ByteStreams;
import com.google.common.io.CharStreams;
import com.google.common.io.Closeables;
import com.google.common.io.Files;
import com.google.common.io.InputSupplier;
/**
* Provides utility methods for working with durable files. All method parameters must be non-null
* unless documented otherwise.
* @author Andres Rodriguez
*/
@Beta
public final class DurableFiles extends NotInstantiable {
/** Not instantiable. */
private DurableFiles() {
}
/**
* Copies to a file all bytes from an {@link InputStream} supplied by a factory. The file is
* sync'd before being closed.
* @param from the input factory
* @param to the destination file
* @throws IOException if an I/O error occurs
*/
public static void copy(InputSupplier extends InputStream> from, File to) throws IOException {
boolean threw = true;
InputStream in = from.getInput();
try {
FileOutputStream os = new FileOutputStream(to);
try {
ByteStreams.copy(in, os);
os.flush();
os.getFD().sync();
threw = false;
} finally {
Closeables.close(os, threw);
}
} finally {
Closeables.close(in, threw);
}
}
/**
* Overwrites a file with the contents of a byte array.The file is sync'd before being closed.
* @param from the bytes to write
* @param to the destination file
* @throws IOException if an I/O error occurs
*/
public static void write(byte[] from, File to) throws IOException {
copy(ByteStreams.newInputStreamSupplier(from), to);
}
/**
* Copies all the bytes from one file to another.The file is sync'd before being closed.
* @param from the source file
* @param to the destination file
* @throws IOException if an I/O error occurs
*/
public static void copy(File from, File to) throws IOException {
copy(Files.newInputStreamSupplier(from), to);
}
/**
* Copies to a file all characters from a {@link Readable} and {@link Closeable} object supplied
* by a factory, using the given character set. The file is sync'd before being closed.
* @param from the readable supplier
* @param to the destination file
* @param charset the character set used when writing the file
* @throws IOException if an I/O error occurs
*/
public static void copy(InputSupplier from, File to, Charset charset)
throws IOException {
boolean threw = true;
FileOutputStream os = new FileOutputStream(to);
try {
OutputStreamWriter w = new OutputStreamWriter(os, charset);
try {
CharStreams.copy(from, w);
w.flush();
os.flush();
os.getFD().sync();
threw = false;
} finally {
Closeables.close(w, threw);
}
} finally {
Closeables.close(os, threw);
}
}
/**
* Writes a character sequence (such as a string) to a file using the given character set. The
* file is sync'd before being closed.
* @param from the character sequence to write
* @param to the destination file
* @param charset the character set used when writing the file
* @throws IOException if an I/O error occurs
*/
public static void write(CharSequence from, File to, Charset charset) throws IOException {
write(from, to, charset, false);
}
/**
* Appends a character sequence (such as a string) to a file using the given character set. The
* file is sync'd before being closed.
* @param from the character sequence to append
* @param to the destination file
* @param charset the character set used when writing the file
* @throws IOException if an I/O error occurs
*/
public static void append(CharSequence from, File to, Charset charset) throws IOException {
write(from, to, charset, true);
}
/**
* Private helper method. Writes a character sequence to a file, optionally appending. The file is
* sync'd before being closed.
* @param from the character sequence to append
* @param to the destination file
* @param charset the character set used when writing the file
* @param append true to append, false to overwrite
* @throws IOException if an I/O error occurs
*/
private static void write(CharSequence from, File to, Charset charset, boolean append) throws IOException {
boolean threw = true;
FileOutputStream os = new FileOutputStream(to, append);
try {
OutputStreamWriter w = new OutputStreamWriter(os, charset);
try {
w.append(from);
w.flush();
os.flush();
os.getFD().sync();
threw = false;
} finally {
Closeables.close(w, threw);
}
} finally {
Closeables.close(os, threw);
}
}
}
© 2015 - 2024 Weber Informatics LLC | Privacy Policy