Mega Code Archive
Utility methods for handling files and directories
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//The contents of this file are subject to the Mozilla Public License Version 1.1
//(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.mozilla.org/MPL/
//
//Software distributed under the License is distributed on an "AS IS" basis,
//WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
//for the specific language governing rights and
//limitations under the License.
//
//The Original Code is "The Columba Project"
//
//The Initial Developers of the Original Code are Frederik Dietz and Timo Stich.
//Portions created by Frederik Dietz and Timo Stich are Copyright (C) 2003.
//
//All Rights Reserved.
import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.net.URL;
import java.util.logging.Logger;
/**
* Utility methods for handling files and directories.
*/
public final class DiskIO {
private static final Logger LOG = Logger.getLogger("org.columba.core.io");
private static String resourceFolder = "";
/**
* Private constructor for utility class.
*/
private DiskIO() {
// don't instantiate this
}
/**
* Ensures the existence of the directory specified by the parameter. If the
* directory does not exist, an attempt is performed to create it including
* all necessary parent directories that may be implied by the
* specification. ### HELPME : against what should a relative pathname be
* made absolute? ### ### We need to set the installation directory
* somewhere! ####
*
* @param dir
* File specifying the intended directory name; if the specified
* name is a relative path, it is always made absolute against
* the program's <b>installationDirectory </b>.
* @return <b>true </b> if and only if the specified file exists and is a
* directory
*/
public static boolean ensureDirectory(File dir) {
if (dir == null) {
throw new IllegalArgumentException("dir = null");
}
boolean success = true;
if (!dir.isDirectory()) {
success = !dir.isFile() && dir.mkdirs();
if (success) {
LOG.info("Created directory: " + dir.toString());
} else {
LOG.severe("failed while trying to create directory: "
+ dir.toString());
}
}
return success;
}
// ensureDirectory
public static boolean ensureDirectory(String path) {
return ensureDirectory(new File(path));
}
public static void saveStringInFile(File toFile, String insertString)
throws IOException {
BufferedWriter out;
out = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(
toFile), "ISO-8859-1"));
out.write(insertString);
out.flush();
out.close();
}
// saveStringInFile
public static String readFileInString(File fromFile) throws IOException {
StringBuffer strbuf = new StringBuffer((int) fromFile.length());
BufferedReader in = new BufferedReader(new InputStreamReader(
new FileInputStream(fromFile), "ISO-8859-1"));
String str;
strbuf = new StringBuffer((int) fromFile.length());
while ((str = in.readLine()) != null) {
strbuf.append(str + "\n");
}
in.close();
return strbuf.toString();
/*
* int lineNumber = 0; byte[] buffer = new byte[1024]; int read;
* StringBuffer out = new StringBuffer((int)fromFile.length());
* FileInputStream in = new FileInputStream( fromFile );
*
* read = in.read(buffer); while ( read == 1024 ) { out.append(new
* String(buffer,"ISO-8859-1")); read = in.read(buffer); }
*
* out.append(new String(buffer,0,read,"ISO-8859-1")); in.close();
*
* return out.toString();
*/
}
// saveStringInFile
/**
* Deletes the directory specified by the parameter and all of its contents.
* This does recurse into subdirectories. Function reports errors. If the
* parameter does not denote a directory, <b>false </b> is always returned.
*
* @param dir
* a File representing the directory to be delete
* @return <b>true </b> if and only if the directory does not exist on
* termination; a return value <b>false </b> does not imply that
* there were no files deleted
* @throws IllegalArgumentException
* if the parameter is <b>null </b>
*/
public static boolean deleteDirectory(File dir) {
File[] files;
File f;
int i;
boolean success = true;
if (dir == null) {
throw new IllegalArgumentException("dir = null");
}
if (!dir.isDirectory()) {
return false;
}
files = dir.listFiles();
for (i = 0; i < files.length; i++) {
if ((f = files[i]).isDirectory()) {
deleteDirectory(f);
} else if (!f.delete()) {
LOG.severe("*** failed to delete file " + f.getAbsolutePath());
}
}
success = dir.delete();
if (!success) {
LOG.severe("*** failed to delete directory "
+ dir.getAbsolutePath());
}
return success;
}
// deleteDirectory
/**
* Deletes the contents of an existing directory. (May be applied to
* non-existing files without causing error.)
*
* @return <b>true </b> if and only if on termination the directory exists
* and is empty
*/
public static boolean emptyDirectory(File dir) {
boolean success;
if (dir == null) {
throw new IllegalArgumentException("dir = null");
}
if ((success = dir.exists() && deleteDirectory(dir))) {
dir.mkdirs();
}
return success && dir.exists();
}
// emptyDirectory
/**
* General use columba resource InputStream getter.
*
* @param path
* the full path and filename of the resource requested. If
* <code>path</code> begins with "#" it is resolved against the
* program's standard resource folder after removing "#"
* @return an InputStream to read the resource data, or <b>null </b> if the
* resource could not be obtained
* @throws java.io.IOException
* if there was an error opening the input stream
*/
public static InputStream getResourceStream(String path)
throws java.io.IOException {
URL url;
if ((url = getResourceURL(path)) == null) {
return null;
}
return url.openStream();
}
// getResourceStream
/**
* General use columba resource URL getter.
*
* @param path
* the full path and filename of the resource requested. If
* <code>path</code> begins with "#" it is resolved against the
* program's standard resource folder after removing "#"
* @return an URL instance, or <b>null </b> if the resource could not be
* obtained
* @throws java.io.IOException
* if there was an error opening the input stream
*/
public static URL getResourceURL(String path) // throws
// java.io.IOException
{
URL url;
if (path == null) {
throw new IllegalArgumentException("path = null");
}
if (path.startsWith("#")) {
path = resourceFolder + path.substring(1);
}
// url = ClassLoader.getSystemResource(path);
url = DiskIO.class.getResource("/" + path);
if (url == null) {
LOG.info("*** failed locating resource: " + path);
return null;
}
return url;
}
// getResourceURL
public static void setResourceRoot(String path) {
if (path == null) {
resourceFolder = "";
} else {
if (!path.endsWith("/")) {
path += "/";
}
resourceFolder = path;
}
}
// setResourceRoot
public static String getResourceRoot() {
return resourceFolder;
}
/**
* Copies the contents of any disk file to the specified output file. The
* output file will be overridden if it exist. Function reports errors.
*
* @param inputFile
* a File object
* @param outputFile
* a File object
* @throws java.io.IOException
* if the function could not be completed because of an IO error
*/
public static void copyFile(File inputFile, File outputFile)
throws java.io.IOException {
FileInputStream in;
FileOutputStream out;
byte[] buffer = new byte[512];
int len;
try {
out = new FileOutputStream(outputFile);
in = new FileInputStream(inputFile);
while ((len = in.read(buffer)) != -1) {
out.write(buffer, 0, len);
}
in.close();
out.close();
} catch (IOException e) {
LOG.info("*** error during file copy "
+ outputFile.getAbsolutePath() + ": " + e.getMessage());
throw e;
}
}
// copyFile
/**
* Copies a system resource to the specified output file. The output file
* will be overridden if it exist, so the calling routine has to take care
* about unwanted deletions of content. Function reports errors.
*
* @param resource
* a full resource path. If the value begins with "#", it is
* resolved against the program's standard resource folder after
* removing "#"
* @return <b>true </b> if and only if the operation was successful,
* <b>false </b> if the resource was not found
* @throws java.io.IOException
* if there was an IO error
*/
public static boolean copyResource(String resource, File outputFile)
throws java.io.IOException {
InputStream in;
FileOutputStream out;
byte[] buffer = new byte[512];
int len;
// attempt
try {
if ((in = DiskIO.getResourceStream(resource)) == null) {
return false;
}
out = new FileOutputStream(outputFile);
while ((len = in.read(buffer)) != -1) {
out.write(buffer, 0, len);
}
out.close();
in.close();
LOG.fine("created : " + outputFile.getAbsolutePath());
} catch (IOException e) {
LOG.severe("*** error during resource file copy "
+ outputFile.getAbsolutePath() + ": " + e.getMessage());
throw e;
}
return true;
}
// copyResource
public static String readStringFromResource(String resource)
throws java.io.IOException {
InputStream in;
StringBuffer result = new StringBuffer();
// attempt
try {
if ((in = DiskIO.getResourceStream(resource)) == null) {
return "";
}
BufferedReader reader = new BufferedReader(
new InputStreamReader(in));
String nextLine = reader.readLine();
while (nextLine != null) {
result.append(nextLine);
result.append("\n");
nextLine = reader.readLine();
}
in.close();
} catch (IOException e) {
e.printStackTrace();
throw e;
}
return result.toString();
}
/**
* Results equal
* <code>copyResource ( String resource, new File (outputFile) )</code>.
*/
public static boolean copyResource(String resource, String outputFile)
throws java.io.IOException {
return copyResource(resource, new File(outputFile));
}
}
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