The Java Tutorials have been written for JDK 8.Java教程是为JDK 8编写的。Examples and practices described in this page don't take advantage of improvements introduced in later releases and might use technology no longer available.本页中描述的示例和实践没有利用后续版本中引入的改进,并且可能使用不再可用的技术。See Java Language Changes for a summary of updated language features in Java SE 9 and subsequent releases.有关Java SE 9及其后续版本中更新的语言特性的摘要,请参阅Java语言更改。
See JDK Release Notes for information about new features, enhancements, and removed or deprecated options for all JDK releases.有关所有JDK版本的新功能、增强功能以及已删除或不推荐的选项的信息,请参阅JDK发行说明。
After you've successfully created a URL
, you can call the URL
's openStream()
method to get a stream from which you can read the contents of the URL. The openStream()
method returns a java.io.InputStream
object, so reading from a URL is as easy as reading from an input stream.
The following small Java program uses openStream()
to get an input stream on the URL http://www.oracle.com/
. It then opens a BufferedReader
on the input stream and reads from the BufferedReader
thereby reading from the URL. Everything read is copied to the standard output stream:
import java.net.*; import java.io.*; public class URLReader { public static void main(String[] args) throws Exception { URL oracle = new URL("http://www.oracle.com/"); BufferedReader in = new BufferedReader( new InputStreamReader(oracle.openStream())); String inputLine; while ((inputLine = in.readLine()) != null) System.out.println(inputLine); in.close(); } }
When you run the program, you should see, scrolling by in your command window, the HTML commands and textual content from the HTML file located at http://www.oracle.com/
. Alternatively, the program might hang or you might see an exception stack trace. If either of the latter two events occurs, you may have to set the proxy host so that the program can find the Oracle server.