Mega Code Archive
Collection of file path related stuff
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import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
/**
* Collection of file path related stuff
* @author eliott bartley
*/
public class PathTools
{
private static class PathList extends ArrayList<String> { }
private PathTools() { }
/**
* Turn a relative path or filename into an absolute one
* @param relativePath The relative path to convert to an absolute one
* @return The absolute path of the <var>relativePath</var>
*/
public static String getAbsolutePath(String relativePath)
{ return getAbsolutePath(relativePath, null, true);
}
/**
* Turn a relative path or filename into an absolute one, relative to a
* directory other than the current directory
* @param relativePath The relative path to convert to an absolute one
* @param workingPath The home path from which the relative path is from. If
* this is null, the current working path is used
* @return The absolute path of the <var>relativePath</var>
*/
public static String getAbsolutePath(String relativePath, String workingPath)
{ return getAbsolutePath(relativePath, workingPath, true);
}
/**
* Turn a relative path or filename into an absolute one
* @param relativePath The relative path to convert to an absolute one
* @param addSlash Specify true if returned path must end with a '/', false
* if it's not important
* @return The absolute path of the <var>relativePath</var>
*/
public static String getAbsolutePath(String relativePath, boolean addSlash)
{ return getAbsolutePath(relativePath, null, addSlash);
}
/**
* Turn a relative path or filename into an absolute one, relative to a
* directory other than the current directory
* @param relativePath The relative path to convert to an absolute one
* @param addSlash Specify true if returned path must end with a '/', false
* if it's not important
* @return The absolute path of the <var>relativePath</var>
*/
public static String getAbsolutePath
( String relativePath,
String workingPath,
boolean addSlash
){ File file;
String path;
if(relativePath == null)
return null;
file = new File(relativePath);
if(file.isAbsolute() == false)
{ file = new File(workingPath, relativePath);
try { path = file.getCanonicalPath(); }
catch(IOException e) { path = file.getAbsolutePath(); }
}
else
path = relativePath;
// Make sure the path end with a '/' if one is required
// (addSlash == true)
if(addSlash == true && file.isDirectory() == true)
path = getSafePath(path);
return path.replace("\\", "/");
}
/**
* Break a path down into individual elements and add to a list.
* example : if a path is /a/b/c/d.txt, the breakdown will be [d.txt,c,b,a]
* @param relativeFile input file
* @return a List collection with the individual elements of the path in
* reverse order
*/
private static PathList getPathList
( String relativePath,
String workingPath
){ PathList pathList = new PathList();
File relativeFile = new File(relativePath);
File pathParser;
try
{
if(workingPath == null || relativeFile.isAbsolute() == true)
pathParser = relativeFile.getCanonicalFile();
else
pathParser = new File
( workingPath,
relativePath
).getCanonicalFile();
for
( ;
pathParser != null;
pathParser = pathParser.getParentFile()
) if(pathParser.getName().length() != 0)
pathList.add(pathParser.getName());
else
pathList.add(pathParser.getPath());
}
catch(IOException e)
{ // This is for debugging only - the user is notified of the error
// when the calling code gets a pathList of null back and tries
// to use it as a valid path, and fails, and then tells the user
// 'path does not exist!' or so -- so this exception shouldn't show
// an error message, other than the debugging one it's showing
// currently (2008y07M31d), which could be removed in the future,
// or, if you don't see it (just under this comment), was removed
// in the past.
System.err.format
( "relativePath [%s] workingPath [%s]%n",
relativePath,
workingPath
);
e.printStackTrace();
pathList = null;
}
return pathList;
}
/**
* Figure out a string representing the relative path of
* 'absolutePath' with respect to 'workingPath'
* @param workingPath home path
* @param absolutePath path of file
*/
private static String parsePathLists
( PathList workingPath,
PathList absolutePath
){ int i;
int j;
StringBuilder relativePath = new StringBuilder();
// start at the beginning of the lists
// iterate while both lists are equal
i = workingPath.size() - 1;
j = absolutePath.size() - 1;
// first eliminate common root
while
( i >= 0 && j >= 0
&& workingPath.get(i).equals(absolutePath.get(j))
){ i--;
j--;
}
// for each remaining level in the home path, add a ..
for(; i>=0; i--)
relativePath.append(".." + File.separator);
// for each level in the file path, add the path
for(; j>=0; j--)
if(j > 0)
relativePath.append(absolutePath.get(j) + File.separator);
else
relativePath.append(absolutePath.get(j));
return relativePath.toString();
}
/**
* Get relative path of absolutePath from the current directory. The
* resulting path will end with a path separator
* @param absolutePath file to generate path for
* @return path from workingPath to absolutePath as a string
*/
public static String getRelativePath
( String absolutePath
){ return getRelativePath(absolutePath, null, true);
}
/**
* Get relative path of absolutePath from the current directory, optionally
* appending the result with a path separator
* @param absolutePath file to generate path for
* @param addSlash true to terminate the result with a path separator
* @return path from workingPath to absolutePath as a string
*/
public static String getRelativePath
( String absolutePath,
boolean addSlash
){ return getRelativePath(absolutePath, null, addSlash);
}
/**
* Get relative path of absolutePath from the current directory. The
* resulting path will end with a path separator
* @param absolutePath file to generate path for
* @param workingPath base path, should be a directory, not a file, or it
* doesn't make sense
* @return path from workingPath to absolutePath as a string
*/
public static String getRelativePath
( String absolutePath,
String workingPath
){ return getRelativePath(absolutePath, workingPath, true);
}
/**
* Get relative path of absolutePath from workingPath, optionally
* appending the result with a path separator
* @param absolutePath file to generate path for
* @param workingPath base path, should be a directory, not a file, or it
* doesn't make sense
* @param addSlash true to terminate the result with a path separator
* @return path from workingPath to absolutePath as a string
*/
public static String getRelativePath
( String absolutePath,
String workingPath,
boolean addSlash
){ String path;
if(workingPath == null)
workingPath = getAbsolutePath(".");
absolutePath = absolutePath.trim();
workingPath = workingPath.trim();
path = parsePathLists
( getPathList(workingPath, null),
getPathList(absolutePath, workingPath)
);
// Make sure the paths end with a '/' if one is required
if(addSlash == true
&& new File(getAbsolutePath(path, workingPath)).isDirectory() == true)
path = getSafePath(path);
return path.replace("\\", "/");
}
/**
* Ensure a path ends with a '/'
* @param path The path to fix
* @return The <var>path</var>, with a trailing '/'
*/
public static String getSafePath(String path)
{ if(path == null || path.length() == 0)
return "./";
if(path.charAt(path.length() - 1) != '/'
&& path.charAt(path.length() - 1) != '\\')
path += "/";
return path;
}
/**
* Build a file list of all the files in the specified directories matching
* the specified wildcard. pathList can contain several paths separated by
* a semi-colon (;) e.g. "c:/.*\\.txt;c:/.*\\.dat" search for *.txt or
* *.dat in c:/. Wildcards use regular expression syntax e.g.
* "c:/[0-9]{5}\\.txt" search for files made up of 5 numeric digits
* followed by .txt. Wildcards can also appear in folder names, e.g.
* "c:/my .* /.*" search for all files under c that are in a folder
* starting my.. i.e. my document, my videos, etc. Folder searches can be
* recursive too, by starting the folder name with N: where N is the
* maximum depth of the search, or * for no limit, e.g. "c:/*:my .* /.*"
* search for all files under all folders in c: (search the whole drive)
* that start my.., or "c:/3:.* /.*\\.txt" search for .txt files in all
* folders up to a maximum of 3 levels deep, i.e. is the same as
* "c:/.* /.* /.* /.*\\.txt". Note: because \\ is regular expression syntax,
* it cannot be used as a path separator, use only / as a path separator
* @param pathList The list of semi-colon (;) separated paths to search
* @return Array of all files matching the path, includes pathname
*/
public static String[] fileList(String pathList)
{ PathList files = new PathList();
String[] paths = pathList.split(";");
for(String path : paths)
fileList("", null, path.split("/"), 0, files, null, 0);
return files.toArray(new String[files.size()]);
}
/**
* Recursively get a list of files matching a given wildcard
* @param base The parent folder that was recursed
* @param folder The folder this recursion is now looking into
* @param folders Array of all folders making up the path
* @param index Index into the folders array that is of importance now
* @param files List of files currently found that matched
* @param wildcard If a folder repeats a wildcard *:.*, the wildcard to
* repeat
* @param repeat If a folder repeats a wildcard, how many more times it
* needs to repeat
*/
private static void fileList
( String base,
String folder,
String[] folders,
int index,
PathList files,
String wildcard,
int repeat
){ File file; // file referring to the current folder
String[] results; // list of files found in current folder
int colon; // locate colon in repeat wildcard 3:.*
int localRepeat; // repeating wildcard at this level, hides wildcard
// inherited during recursion (wilecard, repeat) with
// (folders[index], localRepeat)
// If the folder to check now is unknown, use the folder specified in
// the folder-array. The folder can differ from the folder-array if the
// folder-array had .*, folder will be the actual folder that matched
// that wildcard; folder is initially null, so fix it to the root
// folder to search
if(folder == null)
folder = folders[index];
// Fix up the base so that it now refers to base + current folder
// base is initially ""
base += folder + "/";
// Move on to the next folder, it is what we're looking for now in this
// path
index++;
// Drop one level in the repeat wildcard search, while this is > 0, this
// folder will be searched for the actual folder[index], but also what
// the repeat wildcard is, so c:/*:.*/.*\\.txt will match a .txt in
// c:/a/x.txt, but this repeat will also repeat *:.* under a, so will
// also match c:/a/b/y.txt, etc.. Also, MAX_VALUE means infinity, so
// don't decrement in that case
if(repeat > 0 && repeat < Integer.MAX_VALUE)
repeat--;
// Get a list of files under the current path
file = new File(base);
results = file.list();
// Parse out the repeat information, if any
colon = folders[index].indexOf(':');
localRepeat = 0;
if(colon != -1)
try
{
// Repeat can be N: (where N is a number) or *: - this will not
// match c:/ as c isn't a number or an '*'
String parseRepeat = folders[index].substring(0, colon);
if(parseRepeat.equals("*") == true)
localRepeat = Integer.MAX_VALUE;
else
localRepeat = Integer.parseInt(parseRepeat);
// Update the folder so it no longer includes the X: part
folders[index] = folders[index].substring(colon + 1);
}
catch(NumberFormatException e) { }
// First check against the current wildcard
if(results != null)
// If still looking in folders..
if(index < folders.length - 1)
for(String result : results)
{ if(result.matches(folders[index]) == true)
// Recursively search sub-folders if this folder matched
// the wildcard
fileList
( base,
result,
folders,
index,
files,
// if no repeat is set up, localRepeat will be 0 so
// passing this repeat information will not
// actually repeat if it's not set up to do so
folders[index],
localRepeat
);
}
else
// If reached the last part of the search string, then these are the
// files being searched for, so store the matches
for(String result : results)
if(result.matches(folders[index]) == true)
files.add(base + result);
// Next test all the results against the repeat wildcard, if any
if(results != null
&& repeat > 0)
for(String result : results)
if(result.matches(wildcard) == true)
// Recursively search sub-folders if this folder matched the
// repeat wildcard
fileList
( base,
result,
folders,
// As this is a repeat, bring the index back so the sub-
// dir search uses the same folder as currently used -
// this -1 will propagate all the way up the recursion
// causing all sub-levels, no matter how deep, to reuse
// the same index
index - 1,
files,
wildcard,
repeat
);
}
}
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