| External Interfaces/API | |
The major tasks performed by URLdemo are:
1. Construct a URL Object
The example first calls a constructor on java.net.URL and assigns the resulting object to variable url. The URL constructor takes a single argument, the name of the URL to be accessed, as a string. The constructor checks whether the input URL has a valid form.
url = java.net.URL(...
'http://www.ncsa.uiuc.edu/demoweb/url-primer.html')
2. Open a Connection to the URL
The second statement of the example calls the method, openStream, on the URL object url, to establish a connection with the web site named by the object. The method returns an InputStream object to variable, is, for reading bytes from the site.
is = openStream(url)
3. Set Up a Buffered Stream Reader
The next two lines create a buffered stream reader for characters. The java.io.InputStreamReader constructor is called with the input stream is, to return to variable isr an object that can read characters. Then, the java.io.BufferedReader constructor is called with isr, to return a BufferedReader object to variable br. A buffered reader provides for efficient reading of characters, arrays, and lines.
isr = java.io.InputStreamReader(is) br = java.io.BufferedReader(isr)
4. Read and Display Lines of Text
The final statement reads and displays the first 10 lines of text from the site. Within a MATLAB for statement that iterates 10 times, the BufferedReader method readLine reads a line of text (terminated by a return and/or line feed character) from the site. To display the output in MATLAB, assign it to variable s, without terminating the statement with a semicolon.
for i = 1:10
s = readLine(br)
end
| | Example - Reading a URL | Running the Example | |