How to resolve java.net.MalformedURLException?

问题:

I am getting this error:

java.net.MalformedURLException: Protocol not found[java.lang.StringBuilder] 

When the following line is getting executed:

url = new URL(urlString.toString());

urlString stores the following value:

http://maps.google.com/maps?f=d&hl=en&saddr=25.04202,121.534761&daddr=25.05202,121.554761&ie=UTF8&0&om=0&output=kml

What causes this Exception?

回答1:

Chances are that you didn't clean after changing from

url = new URL( urlString );

to

url = new URL(urlString.toString());

You should log the value of the parameter passed to the constructor of URL. It's not what you think it should be.

urlString would print a value in the form of java.lang.StringBuilder@ thus throwing the exception if you try to build a url out of that.

But using to String will print the value of the content string built by the stringbuilder.

回答2:

Here is an example with exception handling ...

String urlString = "https://www.example.com/";
URL url = null;

// handle Exception
try {
    url = new URL(urlString);
} catch (MalformedURLException e) {
    System.out.println("The URL is not valid.");
    System.out.println(e.getMessage());
}

// print
if (url != null) {
    System.out.println(url.toString());
}

回答3:

You can also get this exception if your network firewall blocking that URL.

回答4:

replace url with php file address placed over server instedof html