Android File Extension Name Get getFileExtensionFromUrl(String url)

Description

Returns the file extension or an empty string if there is no extension.

License

Apache License

Parameter

Parameter	Description
url	a parameter

Return

The file extension of the given url.

Declaration

public static String getFileExtensionFromUrl(String url) 

Method Source Code

//package com.java2s;
//License from project: Apache License 

import java.util.regex.Pattern;

public class Main {
    /**/*from   w w  w  .  java  2s .  c o m*/
     * Returns the file extension or an empty string if there is no extension.
     * This method is a convenience method for obtaining the extension of a url
     * and has undefined results for other Strings.
     *
     * @param url
     * @return The file extension of the given url.
     */
    public static String getFileExtensionFromUrl(String url) {
        if (url != null && url.length() > 0) {
            int query = url.lastIndexOf('?');
            if (query > 0) {
                url = url.substring(0, query);
            }
            int filenamePos = url.lastIndexOf('/');
            String filename = 0 <= filenamePos ? url
                    .substring(filenamePos + 1) : url;

            // if the filename contains special characters, we don't
            // consider it valid for our matching purposes:
            if (filename.length() > 0
                    && Pattern.matches("[a-zA-Z_0-9\\.\\-\\(\\)]+",
                            filename)) {
                int dotPos = filename.lastIndexOf('.');
                if (0 <= dotPos) {
                    return filename.substring(dotPos + 1);
                }
            }
        }

        return "";
    }
}

Related

1. getFileExtension(String fileName)
2. getFileExtension(String filename)
3. getFileExtension(String filename, String defExt)
4. getFileExtensionFromName(String filename)
5. getFileExtensionFromSource(byte[] picHeader)
6. getFilenameExtension(String path)
7. getNameMinusExtension(File file)
8. getPathExtension(final String path)
9. getSuffix(String f)