gov.sandia.cognition.io.FileUtil Maven / Gradle / Ivy
/*
* File: FileUtil.java
* Authors: Justin Basilico
* Company: Sandia National Laboratories
* Project: Cognitive Foundry
*
* Copyright April 27, 2006, Sandia Corporation. Under the terms of Contract
* DE-AC04-94AL85000, there is a non-exclusive license for use of this work by
* or on behalf of the U.S. Government. Export of this program may require a
* license from the United States Government. See CopyrightHistory.txt for
* complete details.
*
*/
package gov.sandia.cognition.io;
import gov.sandia.cognition.annotation.CodeReview;
import java.io.File;
/**
* The FileUtil class defines some useful utilities for dealing
* with files.
*
* @author Justin Basilico
* @since 1.0
*/
@CodeReview(
reviewer="Jonathan McClain",
date="2006-05-11",
changesNeeded=false,
comments="No changes necessary."
)
public final class FileUtil
extends Object
{
/**
* Returns the extension of the given file, which is the part of the name
* after the last '.'.
*
* @param file
* The File to get the extension from.
* @return The extension part of the given File.
* @since 1.0
*/
public static String getExtension(
final File file)
{
return getExtension(file.getName());
}
/**
* Returns the extension of the given filename , which is the part of the
* name after the last '.'.
*
* @param fileName
* The file name to get the extension from.
* @return The extension part of the given file name.
* @since 1.0
*/
public static String getExtension(
final String fileName)
{
String extension = null;
final int index = fileName.lastIndexOf('.');
if (index > 0 && index < fileName.length() - 1)
{
extension = fileName.substring(index + 1);
}
return extension;
}
/**
* Takes a file name and returns the name of the file without the extension
* on it. The extension is determined by finding the last '.' that appears
* in the name. If the last '.' is the first character or there is no '.'
* then the full file name is returned.
*
* @param fileName
* A file name.
* @return The portion of the name before the extension
* @since 2.0
*/
public static String removeExtension(
final String fileName)
{
// Find the last index of the extension.
final int index = fileName.lastIndexOf('.');
if (index <= 0)
{
// No extension so return the whole name.
return fileName;
} else
{
// Return the part before the extension.
return fileName.substring(0, index);
}
}
/**
* Attempts to determine if the application might be able to write to the
* given file, which may or may not already exists. If the file exists,
* it just calls the canWrite() method on it. Otherwise, it looks at its
* parent directory to see if that exists and checks to see if that
* directory can be written to.
*
* @param file
* The file (which may or may not already exist) to see if it can be
* written to.
* @return
* True if it should be possible to write to the given file.
*/
public static boolean couldWrite(
final File file)
{
if (file == null)
{
// Bad file.
return false;
}
else if (file.exists())
{
// Use the existing can-write check.
return file.canWrite();
}
else
{
// Look at the parent directory.
final File parent = file.getParentFile();
if (parent != null)
{
// See if we can write to the parent directory.
return parent.canWrite();
}
return false;
}
}
}