I have a problem to understand the meaning of the connect()
method in the URLConnection
class. In the following code, if I use the connect()
method, I get the same result if I don't use it.
Why (or when) do I need to use it?
URL u = new URL("http://example.com");
HttpURLConnection conn = (HttpURLConnection) u.openConnection();
conn.connect();//with or without it I have the same result
InputStream in = conn.getInputStream();
int b;
while ((b = in.read()) != -1) {
System.out.write(b);
}
Amanda
HttpURLConnection conn = (HttpURLConnection) u.openConnection();
only creates an Object
connect()
method is invoked by conn.getInputStream();
swagat
You are not always required to explicitly call the connect method to initiate the connection.
Operations that depend on being connected, like getInputStream
, getOutputStream
, etc, will implicitly perform the connection, if necessary.
Here's the oracle doc link
来源:https://stackoverflow.com/questions/16122999/java-urlconnection-when-do-i-need-to-use-the-connect-method