Obtener el nombre del archivo desde la URL


En Java, dado un java.net.URL o un String en forma de http://www.example.com/some/path/to/a/file.xml, ¿cuál es la forma más fácil de obtener el nombre del archivo, menos la extensión? Así, en este ejemplo, estoy buscando algo que devuelve "file".

Se me ocurren varias maneras de hacer esto, pero estoy buscando algo que sea fácil de leer y corto.

Author: sevenforce, 2009-03-03

24 answers

En lugar de reinventar la rueda, ¿qué tal usar Apache commons-io :

import org.apache.commons.io.FilenameUtils;

public class FilenameUtilTest {

    public static void main(String[] args) throws Exception {
        URL url = new URL("http://www.example.com/some/path/to/a/file.xml?foo=bar#test");

        System.out.println(FilenameUtils.getBaseName(url.getPath())); // -> file
        System.out.println(FilenameUtils.getExtension(url.getPath())); // -> xml
        System.out.println(FilenameUtils.getName(url.getPath())); // -> file.xml
    }

}
 146
Author: Adrian B.,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2016-10-28 04:10:57
String fileName = url.substring( url.lastIndexOf('/')+1, url.length() );

String fileNameWithoutExtn = fileName.substring(0, fileName.lastIndexOf('.'));
 162
Author: Real Red.,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2009-03-03 09:43:26

Esto debería cortarlo (te dejaré el manejo de errores a ti):

int slashIndex = url.lastIndexOf('/');
int dotIndex = url.lastIndexOf('.', slashIndex);
String filenameWithoutExtension;
if (dotIndex == -1) {
  filenameWithoutExtension = url.substring(slashIndex + 1);
} else {
  filenameWithoutExtension = url.substring(slashIndex + 1, dotIndex);
}
 26
Author: tehvan,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2018-01-24 01:17:56

Si no necesita deshacerse de la extensión de archivo, aquí hay una manera de hacerlo sin recurrir a la manipulación de cadenas propensas a errores y sin usar bibliotecas externas. Funciona con Java 1.7+:

import java.net.URI
import java.nio.file.Paths

String url = "http://example.org/file?p=foo&q=bar"
String filename = Paths.get(new URI(url).getPath()).getFileName().toString()
 15
Author: Zoltán,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2015-11-23 12:23:36
public static String getFileName(URL extUrl) {
        //URL: "http://photosaaaaa.net/photos-ak-snc1/v315/224/13/659629384/s659629384_752969_4472.jpg"
        String filename = "";
        //PATH: /photos-ak-snc1/v315/224/13/659629384/s659629384_752969_4472.jpg
        String path = extUrl.getPath();
        //Checks for both forward and/or backslash 
        //NOTE:**While backslashes are not supported in URL's 
        //most browsers will autoreplace them with forward slashes
        //So technically if you're parsing an html page you could run into 
        //a backslash , so i'm accounting for them here;
        String[] pathContents = path.split("[\\\\/]");
        if(pathContents != null){
            int pathContentsLength = pathContents.length;
            System.out.println("Path Contents Length: " + pathContentsLength);
            for (int i = 0; i < pathContents.length; i++) {
                System.out.println("Path " + i + ": " + pathContents[i]);
            }
            //lastPart: s659629384_752969_4472.jpg
            String lastPart = pathContents[pathContentsLength-1];
            String[] lastPartContents = lastPart.split("\\.");
            if(lastPartContents != null && lastPartContents.length > 1){
                int lastPartContentLength = lastPartContents.length;
                System.out.println("Last Part Length: " + lastPartContentLength);
                //filenames can contain . , so we assume everything before
                //the last . is the name, everything after the last . is the 
                //extension
                String name = "";
                for (int i = 0; i < lastPartContentLength; i++) {
                    System.out.println("Last Part " + i + ": "+ lastPartContents[i]);
                    if(i < (lastPartContents.length -1)){
                        name += lastPartContents[i] ;
                        if(i < (lastPartContentLength -2)){
                            name += ".";
                        }
                    }
                }
                String extension = lastPartContents[lastPartContentLength -1];
                filename = name + "." +extension;
                System.out.println("Name: " + name);
                System.out.println("Extension: " + extension);
                System.out.println("Filename: " + filename);
            }
        }
        return filename;
    }
 13
Author: Mike,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2009-12-06 20:42:35

Get Archivo Nombre con la Extensión de, sin Extensión, sólo la Extensión con sólo 3 línea:

String urlStr = "http://www.example.com/yourpath/foler/test.png";

String fileName = urlStr.substring(urlStr.lastIndexOf('/')+1, urlStr.length());
String fileNameWithoutExtension = fileName.substring(0, fileName.lastIndexOf('.'));
String fileExtension = urlStr.substring(urlStr.lastIndexOf("."));

Log.i("File Name", fileName);
Log.i("File Name Without Extension", fileNameWithoutExtension);
Log.i("File Extension", fileExtension);

Resultado del registro:

File Name(13656): test.png
File Name Without Extension(13656): test
File Extension(13656): .png

Espero que te ayude.

 11
Author: Hiren Patel,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2015-07-17 05:38:20

Se me ha ocurrido esto:

String url = "http://www.example.com/some/path/to/a/file.xml";
String file = url.substring(url.lastIndexOf('/')+1, url.lastIndexOf('.'));
 8
Author: Sietse,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2009-03-03 09:34:36
String fileName = url.substring(url.lastIndexOf('/') + 1);
 7
Author: Yogesh Rathi,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2016-02-16 10:18:13

Manténgalo simple:

/**
 * This function will take an URL as input and return the file name.
 * <p>Examples :</p>
 * <ul>
 * <li>http://example.com/a/b/c/test.txt -> test.txt</li>
 * <li>http://example.com/ -> an empty string </li>
 * <li>http://example.com/test.txt?param=value -> test.txt</li>
 * <li>http://example.com/test.txt#anchor -> test.txt</li>
 * </ul>
 * 
 * @param url The input URL
 * @return The URL file name
 */
public static String getFileNameFromUrl(URL url) {

    String urlString = url.getFile();

    return urlString.substring(urlString.lastIndexOf('/') + 1).split("\\?")[0].split("#")[0];
}
 6
Author: Tim Autin,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2014-11-07 22:01:29

Aquí está la forma más sencilla de hacerlo en Android. Sé que no funcionará en Java, pero puede ayudar al desarrollador de aplicaciones de Android.

import android.webkit.URLUtil;

public String getFileNameFromURL(String url) {
    String fileNameWithExtension = null;
    String fileNameWithoutExtension = null;
    if (URLUtil.isValidUrl(url)) {
        fileNameWithExtension = URLUtil.guessFileName(url, null, null);
        if (fileNameWithExtension != null && !fileNameWithExtension.isEmpty()) {
            String[] f = fileNameWithExtension.split(".");
            if (f != null & f.length > 1) {
                fileNameWithoutExtension = f[0];
            }
        }
    }
    return fileNameWithoutExtension;
}
 5
Author: Bharat Dodeja,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2013-10-11 08:53:14

Un trazador de líneas:

new File(uri.getPath).getName

Código completo:

import java.io.File
import java.net.URI

val uri = new URI("http://example.org/file.txt?whatever")

new File(uri.getPath).getName
res18: String = file.txt

Nota: URI#gePath ya es lo suficientemente inteligente como para eliminar los parámetros de consulta y el esquema del protocolo. Ejemplos:

new URI("http://example.org/hey/file.txt?whatever").getPath
res20: String = /hey/file.txt

new URI("hdfs:///hey/file.txt").getPath
res21: String = /hey/file.txt

new URI("file:///hey/file.txt").getPath
res22: String = /hey/file.txt
 5
Author: juanmirocks,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2017-11-08 15:13:18

Cree un objeto URL a partir de la cadena. La primera vez que tiene un objeto URL hay métodos para extraer fácilmente casi cualquier fragmento de información que necesite.

Puedo recomendar fuertemente el sitio web Javaalmanac que tiene toneladas de ejemplos, pero que desde entonces se ha movido. Usted puede encontrar http://exampledepot.8waytrips.com/egs/java.io/File2Uri.html interesante:

// Create a file object
File file = new File("filename");

// Convert the file object to a URL
URL url = null;
try {
    // The file need not exist. It is made into an absolute path
    // by prefixing the current working directory
    url = file.toURL();          // file:/d:/almanac1.4/java.io/filename
} catch (MalformedURLException e) {
}

// Convert the URL to a file object
file = new File(url.getFile());  // d:/almanac1.4/java.io/filename

// Read the file contents using the URL
try {
    // Open an input stream
    InputStream is = url.openStream();

    // Read from is

    is.close();
} catch (IOException e) {
    // Could not open the file
}
 3
Author: Thorbjørn Ravn Andersen,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2016-09-22 05:37:07

He encontrado que algunas URL cuando se pasan directamente a FilenameUtils.getName devuelven resultados no deseados y esto necesita ser envuelto para evitar exploits.

Por ejemplo,

System.out.println(FilenameUtils.getName("http://www.google.com/.."));

Devuelve

..

Que dudo que alguien quiera permitir.

La siguiente función parece funcionar bien, y muestra algunos de estos casos de prueba, y devuelve null cuando no se puede determinar el nombre del archivo.

public static String getFilenameFromUrl(String url)
{
    if (url == null)
        return null;

    try
    {
        // Add a protocol if none found
        if (! url.contains("//"))
            url = "http://" + url;

        URL uri = new URL(url);
        String result = FilenameUtils.getName(uri.getPath());

        if (result == null || result.isEmpty())
            return null;

        if (result.contains(".."))
            return null;

        return result;
    }
    catch (MalformedURLException e)
    {
        return null;
    }
}

Esto está envuelto con algunos casos de pruebas simples en el ejemplo siguiente:

import java.util.Objects;
import java.net.URL;
import org.apache.commons.io.FilenameUtils;

class Main {

  public static void main(String[] args) {
    validateFilename(null, null);
    validateFilename("", null);
    validateFilename("www.google.com/../me/you?trex=5#sdf", "you");
    validateFilename("www.google.com/../me/you?trex=5 is the num#sdf", "you");
    validateFilename("http://www.google.com/test.png?test", "test.png");
    validateFilename("http://www.google.com", null);
    validateFilename("http://www.google.com#test", null);
    validateFilename("http://www.google.com////", null);
    validateFilename("www.google.com/..", null);
    validateFilename("http://www.google.com/..", null);
    validateFilename("http://www.google.com/test", "test");
    validateFilename("https://www.google.com/../../test.png", "test.png");
    validateFilename("file://www.google.com/test.png", "test.png");
    validateFilename("file://www.google.com/../me/you?trex=5", "you");
    validateFilename("file://www.google.com/../me/you?trex", "you");
  }

  private static void validateFilename(String url, String expectedFilename){
    String actualFilename = getFilenameFromUrl(url);

    System.out.println("");
    System.out.println("url:" + url);
    System.out.println("filename:" + expectedFilename);

    if (! Objects.equals(actualFilename, expectedFilename))
      throw new RuntimeException("Problem, actual=" + actualFilename + " and expected=" + expectedFilename + " are not equal");
  }

  public static String getFilenameFromUrl(String url)
  {
    if (url == null)
      return null;

    try
    {
      // Add a protocol if none found
      if (! url.contains("//"))
        url = "http://" + url;

      URL uri = new URL(url);
      String result = FilenameUtils.getName(uri.getPath());

      if (result == null || result.isEmpty())
        return null;

      if (result.contains(".."))
        return null;

      return result;
    }
    catch (MalformedURLException e)
    {
      return null;
    }
  }
}
 3
Author: Brad Parks,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2016-12-20 14:39:16

Si desea obtener solo el nombre de archivo de un java. net. URL (sin incluir ningún parámetro de consulta), puede usar la siguiente función:

public static String getFilenameFromURL(URL url) {
    return new File(url.getPath().toString()).getName();
}

Por ejemplo, esta URL de entrada:

"http://example.com/image.png?version=2&amp;modificationDate=1449846324000"

Se traduciría a esta cadena de salida:

image.png
 2
Author: dokaspar,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2016-08-25 09:59:57

Las url pueden tener parámetros al final, esto

 /**
 * Getting file name from url without extension
 * @param url string
 * @return file name
 */
public static String getFileName(String url) {
    String fileName;
    int slashIndex = url.lastIndexOf("/");
    int qIndex = url.lastIndexOf("?");
    if (qIndex > slashIndex) {//if has parameters
        fileName = url.substring(slashIndex + 1, qIndex);
    } else {
        fileName = url.substring(slashIndex + 1);
    }
    if (fileName.contains(".")) {
        fileName = fileName.substring(0, fileName.lastIndexOf("."));
    }

    return fileName;
}
 1
Author: Serhii Bohutskyi,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2013-10-31 20:39:17

El objeto Url en urllib le permite acceder al nombre de archivo no registrado de la ruta. Estos son algunos ejemplos:

String raw = "http://www.example.com/some/path/to/a/file.xml";
assertEquals("file.xml", Url.parse(raw).path().filename());

raw = "http://www.example.com/files/r%C3%A9sum%C3%A9.pdf";
assertEquals("résumé.pdf", Url.parse(raw).path().filename());
 1
Author: EricE,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2017-11-12 20:16:17

Respuesta de Andy rehecha usando split ():

Url u= ...;
String[] pathparts= u.getPath().split("\\/");
String filename= pathparts[pathparts.length-1].split("\\.", 1)[0];
 0
Author: bobince,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2009-03-03 10:35:10
public String getFileNameWithoutExtension(URL url) {
    String path = url.getPath();

    if (StringUtils.isBlank(path)) {
        return null;
    }
    if (StringUtils.endsWith(path, "/")) {
        //is a directory ..
        return null;
    }

    File file = new File(url.getPath());
    String fileNameWithExt = file.getName();

    int sepPosition = fileNameWithExt.lastIndexOf(".");
    String fileNameWithOutExt = null;
    if (sepPosition >= 0) {
        fileNameWithOutExt = fileNameWithExt.substring(0,sepPosition);
    }else{
        fileNameWithOutExt = fileNameWithExt;
    }

    return fileNameWithOutExt;
}
 0
Author: Campa,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2011-06-23 07:56:25

¿qué tal esto:

String filenameWithoutExtension = null;
String fullname = new File(
    new URI("http://www.xyz.com/some/deep/path/to/abc.png").getPath()).getName();

int lastIndexOfDot = fullname.lastIndexOf('.');
filenameWithoutExtension = fullname.substring(0, 
    lastIndexOfDot == -1 ? fullname.length() : lastIndexOfDot);
 0
Author: Bowie,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2013-06-15 09:15:24

Para devolver filename sin extensión y sin parámetros use lo siguiente:

String filenameWithParams = FilenameUtils.getBaseName(urlStr); // may hold params if http://example.com/a?param=yes
return filenameWithParams.split("\\?")[0]; // removing parameters from url if they exist

Para devolver nombre de archivo con extensión sin parámetros use esto:

/** Parses a URL and extracts the filename from it or returns an empty string (if filename is non existent in the url) <br/>
 * This method will work in win/unix formats, will work with mixed case of slashes (forward and backward) <br/>
 * This method will remove parameters after the extension
 *
 * @param urlStr original url string from which we will extract the filename
 * @return filename from the url if it exists, or an empty string in all other cases */
private String getFileNameFromUrl(String urlStr) {
    String baseName = FilenameUtils.getBaseName(urlStr);
    String extension = FilenameUtils.getExtension(urlStr);

    try {
        extension = extension.split("\\?")[0]; // removing parameters from url if they exist
        return baseName.isEmpty() ? "" : baseName + "." + extension;
    } catch (NullPointerException npe) {
        return "";
    }
}
 0
Author: Chaiavi,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2015-07-29 09:24:54

Más allá de todos los métodos avanzados, mi truco simple es StringTokenizer:

import java.util.ArrayList;
import java.util.StringTokenizer;

public class URLName {
    public static void main(String args[]){
        String url = "http://www.example.com/some/path/to/a/file.xml";
        StringTokenizer tokens = new StringTokenizer(url, "/");

        ArrayList<String> parts = new ArrayList<>();

        while(tokens.hasMoreTokens()){
            parts.add(tokens.nextToken());
        }
        String file = parts.get(parts.size() -1);
        int dot = file.indexOf(".");
        String fileName = file.substring(0, dot);
        System.out.println(fileName);
    }
}
 0
Author: Blasanka,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2017-05-31 12:37:21

Hay algunas maneras:

E/S de archivo Java 7:

String fileName = Paths.get(strUrl).getFileName().toString();

Apache Commons:

String fileName = FilenameUtils.getName(strUrl);

Usando Jersey:

UriBuilder buildURI = UriBuilder.fromUri(strUrl);
URI uri = buildURI.build();
String fileName = Paths.get(uri.getPath()).getFileName();

Subcadena:

String fileName = strUrl.substring(strUrl.lastIndexOf('/') + 1);
 0
Author: Giang Phan,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2018-07-07 07:57:05
create a new file with string image path

    String imagePath;
    File test = new File(imagePath);
    test.getName();
    test.getPath();
    getExtension(test.getName());


    public static String getExtension(String uri) {
            if (uri == null) {
                return null;
            }

            int dot = uri.lastIndexOf(".");
            if (dot >= 0) {
                return uri.substring(dot);
            } else {
                // No extension.
                return "";
            }
        }
 -1
Author: Pravin Bhosale,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2015-02-02 14:40:29

Importar java.io.*;

import java.net.*;

public class ConvertURLToFileName{


   public static void main(String[] args)throws IOException{
   BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
   System.out.print("Please enter the URL : ");

   String str = in.readLine();


   try{

     URL url = new URL(str);

     System.out.println("File : "+ url.getFile());
     System.out.println("Converting process Successfully");

   }  
   catch (MalformedURLException me){

      System.out.println("Converting process error");

 }

Espero que esto te ayude.

 -3
Author: Ricardo Felgueiras,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/ajaxhispano.com/template/agent.layouts/content.php on line 61
2009-03-03 10:13:02