import java.net.MalformedURLException;
import java.net.URL;


public class dd {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		try {
			URL url = new URL("file://ftp.yoyodyne.com/pub/files/foobar.txt?id=123456");
			System.out.println("url.getFile()="+url.getFile());
			System.out.println("url.getPath()="+url.getPath());
		} catch (MalformedURLException e) {
			e.printStackTrace();
		}
	}
}
 

返回的結果：

url.getFile()=/pub/files/foobar.txt?id=123456
url.getPath()=/pub/files/foobar.txt

當將上面的

file://ftp.yoyodyne.com/pub/files/foobar.txt?id=123456

file://ftp.yoyodyne.com/pub/files/foobar.txt

返回的結果：

url.getFile()=/pub/files/foobar.txt
url.getPath()=/pub/files/foobar.txt

java docs文件上說的：

The URL.getFile() javadocs say this:

Gets the file name of this URL. The returned file portion will be the same as getPath(), plus the concatenation of the value of getQuery(), if any. If there is no query portion, this method and getPath() will return identical results.

They will be the same unless there is a query string, e.g. a ?somename=value&somethingelse=value2