com.pixelmed.utils

Class FileUtilities

java.lang.Object

com.pixelmed.utils.FileUtilities

public class FileUtilities
extends java.lang.Object

Various static methods helpful for handling files.

Method Summary

Modifier and Type	Method and Description
static java.lang.String	digest(java.io.InputStream in, java.lang.String algorithm) Return a message digest of an InputStream.
static java.lang.String	digest(java.lang.String fileName, java.lang.String algorithm) Return a message digest of a file.
static java.util.ArrayList<java.lang.String>	getCanonicalFileNames(java.util.ArrayList<java.io.File> files)
static java.io.File	getFileFromNameInsensitiveToCaseIfNecessary(java.lang.String fileName) Determine if a file corresponding to the specified name exists, checking for case insensitive variants if necessary.
static java.util.List<java.lang.String>	getFilePathComponents(java.io.File path) Get the individual components of the canonical form of the path as a list.
static java.util.ArrayList<java.io.File>	listFilesRecursively(java.io.File initialPath) Recursively traverse the specified directory and its sub-directory and produce a list of all the files contained therein, in no particular order.
static java.lang.String	makePathToFileInUsersHomeDirectory(java.lang.String fileName) Given a file name, such as the properties file name, make a path to it in the user's home directory.
static java.io.File	makeSameRelativePathNameInDifferentFolder(java.io.File srcFolder, java.io.File dstFolder, java.io.File srcFile) Create a new path that re-creates the relative path of the source file in the destination folder.
static java.io.File	makeSameRelativePathNameInDifferentFolder(java.lang.String srcFolderName, java.lang.String dstFolderName, java.lang.String srcFileName) Create a new path that re-creates the relative path of the source file in the destination folder.
static java.lang.String	makeTemporaryFileName() Create a temporary filename.
static java.lang.String	md5(java.io.InputStream in) Return an MD5 message digest of an InputStream.
static java.lang.String	md5(java.lang.String fileName) Return an MD5 message digest of a file.
static byte[]	readAllBytes(java.io.InputStream stream) Read an entire input stream, such as from a resource in a jar file, into an array of bytes.
static java.lang.String	readFile(java.io.File file) Read an entire file into a string.
static java.lang.String	readFile(java.io.InputStream stream) Read an entire file into a string.
static java.lang.String	readFile(java.io.Reader reader) Read an entire file into a string.
static java.lang.String	readFile(java.lang.String filename) Read an entire file into a string.
static void	renameElseCopyTo(java.io.File srcFile, java.io.File dstFile) Rename a file, if possible, else make a copy of it.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

digest

public static final java.lang.String digest(java.io.InputStream in,
                                            java.lang.String algorithm)
                                     throws java.io.IOException,
                                            java.security.NoSuchAlgorithmException

Return a message digest of an InputStream.

Parameters:

in - the InputStream

algorithm - the digest algorithm, such as "MD5" or "SHA"

Returns:

string representation of the digest

Throws:

java.io.IOException

java.security.NoSuchAlgorithmException

digest

public static final java.lang.String digest(java.lang.String fileName,
                                            java.lang.String algorithm)
                                     throws java.io.IOException,
                                            java.security.NoSuchAlgorithmException

Return a message digest of a file.

Parameters:

fileName - the file name

algorithm - the digest algorithm, such as "MD5" or "SHA"

Returns:

string representation of the digest

Throws:

java.io.IOException

java.security.NoSuchAlgorithmException

getCanonicalFileNames

public static final java.util.ArrayList<java.lang.String> getCanonicalFileNames(java.util.ArrayList<java.io.File> files)
                                                                         throws java.io.IOException

Throws:

java.io.IOException

getFileFromNameInsensitiveToCaseIfNecessary

public static final java.io.File getFileFromNameInsensitiveToCaseIfNecessary(java.lang.String fileName)
                                                                      throws java.io.FileNotFoundException

Determine if a file corresponding to the specified name exists, checking for case insensitive variants if necessary.

Parameters:

fileName - The name of the file to find

Returns:

A file if found.

Throws:

java.io.FileNotFoundException - If the file cannot be found.

getFilePathComponents

public static java.util.List<java.lang.String> getFilePathComponents(java.io.File path)
                                                              throws java.io.IOException

Get the individual components of the canonical form of the path as a list.

Parameters:

path -

Returns:

each component of the path, starting with the root

Throws:

java.io.IOException

listFilesRecursively

public static final java.util.ArrayList<java.io.File> listFilesRecursively(java.io.File initialPath)

Recursively traverse the specified directory and its sub-directory and produce a list of all the files contained therein, in no particular order.

If the path is a file, just return that.

Any security (permission) exceptions are caught and logged to stderr and not propagated.

Parameters:

initialPath - The abstract pathname of the directory to begin searching

Returns:

An ArrayList of abstract pathnames denoting the files found. The ArrayList will be empty if the path is empty or does not exist or if an error occurs.

makePathToFileInUsersHomeDirectory

public static final java.lang.String makePathToFileInUsersHomeDirectory(java.lang.String fileName)

Given a file name, such as the properties file name, make a path to it in the user's home directory.

Parameters:

fileName - the file name to make a path to

makeSameRelativePathNameInDifferentFolder

public static java.io.File makeSameRelativePathNameInDifferentFolder(java.io.File srcFolder,
                                                                     java.io.File dstFolder,
                                                                     java.io.File srcFile)
                                                              throws java.io.IOException

Create a new path that re-creates the relative path of the source file in the destination folder.

Parameters:

srcFolder -

dstFolder -

srcFile -

Returns:

a File in the destination folder

Throws:

java.io.IOException

makeSameRelativePathNameInDifferentFolder

public static java.io.File makeSameRelativePathNameInDifferentFolder(java.lang.String srcFolderName,
                                                                     java.lang.String dstFolderName,
                                                                     java.lang.String srcFileName)
                                                              throws java.io.IOException

Create a new path that re-creates the relative path of the source file in the destination folder.

Parameters:

srcFolderName -

dstFolderName -

srcFileName -

Returns:

a File in the destination folder

Throws:

java.io.IOException

makeTemporaryFileName

public static final java.lang.String makeTemporaryFileName()

Create a temporary filename.

Returns:

a string that does not include delimiter characters and is unique within this JVM.

md5

public static final java.lang.String md5(java.io.InputStream in)
                                  throws java.io.IOException,
                                         java.security.NoSuchAlgorithmException

Return an MD5 message digest of an InputStream.

Parameters:

in - the InputStream

Returns:

string representation of the digest

Throws:

java.io.IOException

java.security.NoSuchAlgorithmException

md5

public static final java.lang.String md5(java.lang.String fileName)
                                  throws java.io.IOException,
                                         java.security.NoSuchAlgorithmException

Return an MD5 message digest of a file.

Parameters:

fileName - the file name

Returns:

string representation of the digest

Throws:

java.io.IOException

java.security.NoSuchAlgorithmException

readAllBytes

public static byte[] readAllBytes(java.io.InputStream stream)
                           throws java.io.IOException

Read an entire input stream, such as from a resource in a jar file, into an array of bytes.

Modelled after Files.readAllBytes(InputStream(Path path), from which the following description is paraphrased:

Reads all the bytes from an input stream. The method ensures that the input stream is closed when all bytes have been read or an I/O error, or other runtime exception, is thrown.

Note that this method is intended for simple cases where it is convenient to read all bytes into a byte array. It is not intended for reading in large input streams.

Parameters:

stream - The input stream (e.g., from class.getResourceAsStream())

Returns:

The contents of the stream

Throws:

java.io.IOException - If an IO error occurs.

readFile

public static final java.lang.String readFile(java.io.File file)
                                       throws java.io.IOException

Read an entire file into a string.

Parameters:

file - The file

Returns:

The contents of the file as a String.

Throws:

java.io.IOException - If an IO error occurs.

readFile

public static final java.lang.String readFile(java.io.InputStream stream)
                                       throws java.io.IOException

Read an entire file into a string.

Parameters:

stream - The input stream (e.g., from class.getResourceAsStream())

Returns:

The contents of the file as a String.

Throws:

java.io.IOException - If an IO error occurs.

readFile

public static final java.lang.String readFile(java.io.Reader reader)
                                       throws java.io.IOException

Read an entire file into a string.

Parameters:

reader - The file reader

Returns:

The contents of the file as a String.

Throws:

java.io.IOException - If an IO error occurs.

readFile

public static final java.lang.String readFile(java.lang.String filename)
                                       throws java.io.IOException

Read an entire file into a string.

Parameters:

filename - The file

Returns:

The contents of the file as a String.

Throws:

java.io.IOException - If an IO error occurs.

renameElseCopyTo

public static final void renameElseCopyTo(java.io.File srcFile,
                                          java.io.File dstFile)
                                   throws java.io.IOException

Rename a file, if possible, else make a copy of it.

Parameters:

srcFile - the source

dstFile - the destination

Throws:

java.io.IOException - thrown if the copying fails for any reason