/*
* Copyright 2006-2007 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 org.springframework.batch.item.util;
import java.io.File;
import java.io.IOException;
import org.springframework.batch.item.ItemStreamException;
import org.springframework.util.Assert;
/**
* Utility methods for files used in batch processing.
*
* @author Peter Zozom
*/
public final class FileUtils {
// forbids instantiation
private FileUtils() {
}
/**
* Set up output file for batch processing. This method implements common logic for handling output files when
* starting or restarting file I/O. When starting output file processing, creates/overwrites new file. When
* restarting output file processing, checks whether file is writable.
*
* @param file file to be set up
* @param restarted true signals that we are restarting output file processing
* @param append true signals input file may already exist (but doesn't have to)
* @param overwriteOutputFile If set to true, output file will be overwritten (this flag is ignored when processing
* is restart)
*
* @throws IllegalArgumentException when file is null
* @throws ItemStreamException when starting output file processing, file exists and flag "overwriteOutputFile" is
* set to false
* @throws ItemStreamException when unable to create file or file is not writable
*/
public static void setUpOutputFile(File file, boolean restarted, boolean append, boolean overwriteOutputFile) {
Assert.notNull(file);
try {
if (!restarted) {
if (!append) {
if (file.exists()) {
if (!overwriteOutputFile) {
throw new ItemStreamException("File already exists: [" + file.getAbsolutePath() + "]");
}
if (!file.delete()) {
throw new IOException("Could not delete file: " + file);
}
}
if (file.getParent() != null) {
new File(file.getParent()).mkdirs();
}
if (!createNewFile(file)) {
throw new ItemStreamException("Output file was not created: [" + file.getAbsolutePath() + "]");
}
}
else {
if (!file.exists()) {
if (file.getParent() != null) {
new File(file.getParent()).mkdirs();
}
if (!createNewFile(file)) {
throw new ItemStreamException("Output file was not created: [" + file.getAbsolutePath()
+ "]");
}
}
}
}
}
catch (IOException ioe) {
throw new ItemStreamException("Unable to create file: [" + file.getAbsolutePath() + "]", ioe);
}
if (!file.canWrite()) {
throw new ItemStreamException("File is not writable: [" + file.getAbsolutePath() + "]");
}
}
/**
* @deprecated use the version with explicit append parameter instead. Here append=false is assumed.
*/
public static void setUpOutputFile(File file, boolean restarted, boolean overwriteOutputFile) {
setUpOutputFile(file, restarted, false, overwriteOutputFile);
}
/**
* Create a new file if it doesn't already exist.
*
* @param file the file to create on the filesystem
*/
public static boolean createNewFile(File file) throws IOException {
if (file.exists()) {
return false;
}
try {
return file.createNewFile() && file.exists();
}
catch (IOException e) {
// On some file systems you can get an exception here even though the
// files was successfully created
if (file.exists()) {
return true;
}
else {
throw e;
}
}
}
}