Java URL to File Name getFileName(URLConnection urlC)

Description

Returns the file name associated to an url connection.
The result is not a path but just a file name.

License

Apache License

Parameter

Parameter	Description
urlC	- the url connection

Exception

Parameter	Description
IOException	Signals that an I/O exception has occurred.

Return

the file name

Declaration

public static final String getFileName(URLConnection urlC) throws IOException 

Method Source Code

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

import java.io.IOException;

import java.net.URLConnection;
import java.util.StringTokenizer;

public class Main {
    /**//from ww  w .  ja  v  a2 s . c om
     * Returns the file name associated to an url connection.<br />
     * The result is not a path but just a file name.
     * 
     * @param urlC
     *            - the url connection
     * @return the file name
     * 
     * @throws IOException
     *             Signals that an I/O exception has occurred.
     */
    public static final String getFileName(URLConnection urlC) throws IOException {
        String fileName = null;

        String contentDisposition = urlC.getHeaderField("content-disposition");

        if (contentDisposition != null) {
            fileName = extractFileNameFromContentDisposition(contentDisposition);
        }

        // if the file name cannot be extracted from the content-disposition
        // header, using the url.getFilename() method
        if (fileName == null) {
            StringTokenizer st = new StringTokenizer(urlC.getURL().getFile(), "/");
            while (st.hasMoreTokens())
                fileName = st.nextToken();
        }
        //if(FileUtility.checkFileExistence(fileName))
        return fileName;
    }

    /**
     * Extract the file name from the content disposition header.
     * <p>
     * See <a
     * href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec19.html">http:
     * //www.w3.org/Protocols/rfc2616/rfc2616-sec19.html</a> for detailled
     * information regarding the headers in HTML.
     * 
     * @param contentDisposition
     *            - the content-disposition header. Cannot be <code>null>/code>.
     * @return the file name, or <code>null</code> if the content-disposition
     *         header does not contain the filename attribute.
     */
    public static final String extractFileNameFromContentDisposition(String contentDisposition) {
        System.out.println("content disposition = " + contentDisposition);
        String[] attributes = contentDisposition.split(";");

        for (String a : attributes) {
            if (a.toLowerCase().contains("filename")) {
                // The attribute is the file name. The filename is between
                // quotes.
                try {
                    return a.substring(a.indexOf('\"') + 1, a.lastIndexOf('\"'));
                } catch (Exception e) {
                    return a.substring(a.indexOf('=') + 1, a.length());
                }
            }
        }

        // not found
        return null;
    }
}

Related

1. getFileName(URL url)
2. getFileName(URL url)
3. getFileName(URL url)
4. getFileName(URL url)
5. getFileName(URL url)
6. getFileName2(String url)
7. getFileNameArray(String url)
8. getFileNameFromContentDisposition(URLConnection connection)
9. getFileNameFromUrl(URL inputUrl)