Hello everyone,
I have this string:
String frase ="c:\\movies\\animals\\crazy cat.avi";
What I want is to get as a final string, in this case, "crazy cat.avi". The problem is that the String Tokenizer counts the spaces as well...
Please help me creating a cycle that looks for the the last "\" and creates a string from then on.
Thanks for any help you might provide!
XonaDick
No need to use a string tokenizer for this task.
Different operating system but you get the idea.
$ cat Test.java
import java.io.*;
public class Test
{
public static void main(String[] args)
{
File f = new File("/var/tmp/some file.txt");
System.out.println(f.getName());
}
}
$ javac Test.java
$ java Test
some file.txt
StringTokenizer st = new StringTokenizer(myString,"\\");
then get the last token with something like
String iWant = null;
int tokens = st.countTokens();
int c=0;
while(c<tokens-1) iWant = st.nextToken();
or something like this.>
> The File method has the advantage of working regardless of what your path seperator character
> happens to be on your current platform. Not everyone runs Windows you know.
Odd, I'm running OS X, and get the following:import java.io.File;
public class LastName {
public static String lastName1 (String str) {
return new File(str).getName();
}
public static String lastName2 (String str) {
String[] parts = str.split("\\\\ "); // added extra space so rest of post doesn't go blue
return parts[parts.length-1];
}
public static String lastName3 (String str) {
return str.substring(str.lastIndexOf('\\')+1);
}
public static void main(String[] args) {
String frase ="c:\\movies\\animals\\crazy cat.avi";
System.out.println(lastName1(frase));
System.out.println(lastName2(frase));
System.out.println(lastName3(frase));
}
}
pete% java LastName
c:\movies\animals\crazy cat.avi
crazy cat.avi
crazy cat.avi
So mine and matfud's methods generate the specified output from the specified input when not on Windows, whereas using the File class doesn't. For all we know he's running VMS and has to process a file that someone on Windows mailed him.
If the OP had asked for way of splitting a file name from the path in the current OS, I'd have posted frase.substring(frase.lastIndexOf(File.pathSeparatorChar)+1)
> was also correct - wonder what's the performance of both since I suggested using a loop...
Testing the File version, the substring version and the split version yields the following:
Filemean of (10 tests, excluding 6 outliers): 2259.446756ms
Splitmean of (10 tests, excluding 6 outliers): 8568.243067ms
Substring mean of (10 tests, excluding 6 outliers): 612.146675ms
each test being 1000000 calls to the method, so about 10% confidence.
Pete
It does not surprise me that lastIndexOf is the fastest. split is a regexp and
there is a lot of work to be done internally. It is strange that File does not
work though. I would have thought that File would have methods to do just thing
on all platforms in a uniform manner.
matfud
File splits up the path with the OS's path separator-the OP asked to split with a specific char, that happens to be the Windows path separator. As I'm not on Windows, then the results for using File.getName() on the string in the OP aren't what they would be on Windows.
If the string had used the unix path separator, then File would 'work' on my system, and also (IIRC) on Windows as Java automatically converts / to \ in the Win runtime. The OS specific behaviour that File gives may be what the OP wanted, or maybe not.
Pete
> Odd, I'm running OS X, and get the
> following:
I'd suppose thats because the file, "c:\\whatever" isn't
valid on your os ... (i.e. File.exists() would fail) ... the File
class doesn't seem (other than the 'normalize' function
which is native) to check the validitiy of the filename you
pass it for you os.