Does groovy have an easy way to get a filename without the extension?
Say I have something like this:
new File("test").eachFile() { file->
println file.getName()
}
This prints the full filename of every file in the test
directory. Is there a Groovy way to get the filename without any extension? (Or am I back in regex la开发者_开发问答nd?)
I believe the grooviest way would be:
file.name.lastIndexOf('.').with {it != -1 ? file.name[0..<it] : file.name}
or with a simple regexp:
file.name.replaceFirst(~/\.[^\.]+$/, '')
also there's an apache commons-io java lib for that kinda purposes, which you could easily depend on if you use maven:
org.apache.commons.io.FilenameUtils.getBaseName(file.name)
The cleanest way.
String fileWithoutExt = file.name.take(file.name.lastIndexOf('.'))
Simplest way is:
'file.name.with.dots.tgz' - ~/\.\w+$/
Result is:
file.name.with.dots
new File("test").eachFile() { file->
println file.getName().split("\\.")[0]
}
This works well for file names like: foo, foo.bar
But if you have a file foo.bar.jar, then the above code prints out: foo If you want it to print out foo.bar instead, then the following code achieves that.
new File("test").eachFile() { file->
def names = (file.name.split("\\.")
def name = names.size() > 1 ? (names - names[-1]).join('.') : names[0]
println name
}
The FilenameUtils class, which is part of the apache commons io package, has a robust solution. Example usage:
import org.apache.commons.io.FilenameUtils
String filename = '/tmp/hello-world.txt'
def fileWithoutExt = FilenameUtils.removeExtension(filename)
This isn't the groovy way, but might be helpful if you need to support lots of edge cases.
Maybe not as easy as you expected but working:
new File("test").eachFile {
println it.name.lastIndexOf('.') >= 0 ?
it.name[0 .. it.name.lastIndexOf('.')-1] :
it.name
}
As mentioned in comments, where a filename ends & an extension begins depends on the situation. In my situation, I needed to get the basename (file without path, and without extension) of the following types of files: { foo.zip
, bar/foo.tgz
, foo.tar.gz
} => all need to produce "foo
" as the filename sans extension. (Most solutions, given foo.tar.gz
would produce foo.tar
.)
Here's one (obvious) solution that will give you everything up to the first "."; optionally, you can get the entire extension either in pieces or (in this case) as a single remainder (splitting the filename into 2
parts). (Note: although unrelated to the task at hand, I'm also removing the path as well, by calling file.name
.)
file=new File("temp/foo.tar.gz")
file.name.split("\\.", 2)[0] // => return "foo" at [0], and "tar.gz" at [1]
You can use regular expressions better. A function like the following would do the trick:
def getExtensionFromFilename(filename) {
def returned_value = ""
m = (filename =~ /(\.[^\.]*)$/)
if (m.size()>0) returned_value = ((m[0][0].size()>0) ? m[0][0].substring(1).trim().toLowerCase() : "");
return returned_value
}
Note
import java.io.File;
def fileNames = [ "/a/b.c/first.txt",
"/b/c/second",
"c:\\a\\b.c\\third...",
"c:\\a\b\\c\\.text"
]
def fileSeparator = "";
fileNames.each {
// You can keep the below code outside of this loop. Since my example
// contains both windows and unix file structure, I am doing this inside the loop.
fileSeparator= "\\" + File.separator;
if (!it.contains(File.separator)) {
fileSeparator = "\\/"
}
println "File extension is : ${it.find(/((?<=\.)[^\.${fileSeparator}]+)$/)}"
it = it.replaceAll(/(\.([^\.${fileSeparator}]+)?)$/,"")
println "Filename is ${it}"
}
Some of the below solutions (except the one using apache library) doesn't work for this example - c:/test.me/firstfile
If I try to find an extension for above entry, I will get ".me/firstfile" - :(
Better approach will be to find the last occurrence of File.separator if present and then look for filename or extension.
Note: (There is a little trick happens below. For Windows, the file separator is \. But this is a special character in regular expression and so when we use a variable containing the File.separator in the regular expression, I have to escape it. That is why I do this:
def fileSeparator= "\\" + File.separator;
Hope it makes sense :)
Try this out:
import java.io.File;
String strFilename = "C:\\first.1\\second.txt";
// Few other flavors
// strFilename = "/dd/dddd/2.dd/dio/dkljlds.dd"
def fileSeparator= "\\" + File.separator;
if (!strFilename.contains(File.separator)) {
fileSeparator = "\\/"
}
def fileExtension = "";
(strFilename =~ /((?<=\.)[^\.${fileSeparator}]+)$/).each { match, extension -> fileExtension = extension }
println "Extension is:$fileExtension"
// Create an instance of a file (note the path is several levels deep)
File file = new File('/tmp/whatever/certificate.crt')
// To get the single fileName without the path (but with EXTENSION! so not answering the question of the author. Sorry for that...)
String fileName = file.parentFile.toURI().relativize(file.toURI()).getPath()
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