-- 作者:admin
-- 发布时间:2008/10/28 20:21:20
-- 程序代码——多线程网页获取方法
import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.InputStream;
import javax.microedition.io.Connector; import javax.microedition.io.ContentConnection; import javax.microedition.lcdui.Alert; import javax.microedition.lcdui.AlertType; import javax.microedition.lcdui.Command; import javax.microedition.lcdui.CommandListener; import javax.microedition.lcdui.Display; import javax.microedition.lcdui.Displayable; import javax.microedition.lcdui.Form; import javax.microedition.lcdui.TextBox; import javax.microedition.lcdui.TextField; import javax.microedition.midlet.MIDlet;
public class Exec extends MIDlet implements CommandListener { Display display; Form form = new Form("练习"); TextField tf; Command ok = new Command("开始", Command.OK, 1); Command cancel = new Command("取消", Command.OK, 1); Command back = new Command("再来", Command.BACK, 1); Alert info = new Alert("消息", "正在下载...", null, AlertType.INFO); TextBox tb = new TextBox("网页文本", "", 100, TextField.ANY); boolean cacncelFlag = false;
public Exec() { display = Display.getDisplay(this); }
public void startApp() { tf = new TextField("URL:", "", 50, TextField.ANY); form.append(tf); form.addCommand(ok); form.setCommandListener(this); display.setCurrent(form); }
public void pauseApp() { }
public void destroyApp(boolean unconditional) { }
public void commandAction(Command com, Displayable disp) { if (com == ok) { cacncelFlag = false; Downloader downloader = new Downloader(tf.getString(), this); Thread thread = new Thread(downloader); thread.start(); info.setTimeout(10000); info.addCommand(cancel); info.setCommandListener(this); display.setCurrent(info); } else if (com == cancel) { cacncelFlag = true; display.setCurrent(form); } else if (com == back) { display.setCurrent(form); } }
public void setResults(String str) { tb.setMaxSize(str.length()); tb.setString(str); tb.addCommand(back); tb.setCommandListener(this); display.setCurrent(tb); }
public boolean isCacncelFlag() { return cacncelFlag; }
}
class Downloader implements Runnable { String url; Exec midlet;
public Downloader(String url, Exec midlet) { this.url = url; this.midlet = midlet; }
public void run() { ContentConnection con = null; InputStream is = null; try { con = (ContentConnection) Connector.open(url); is = con.openInputStream(); ByteArrayOutputStream baos = new ByteArrayOutputStream(); byte[] dataArray = null; int ch = 0; while ((ch = is.read()) != -1 && !midlet.isCacncelFlag()) { baos.write(ch); } if (!midlet.isCacncelFlag()) { dataArray = baos.toByteArray(); midlet.setResults(new String(dataArray)); }
} catch (Exception e) { System.out.println(e.getMessage());
} finally { if (is != null) try { is.close(); } catch (IOException e) { System.out.println(e.getMessage()); } if (con != null) try { con.close(); } catch (IOException e) { System.out.println(e.getMessage()); } } }
}
[此贴子已经被作者于2010-12-12 18:43:40编辑过]
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