httpgetdata.java

J2me访问网站的源码

import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import javax.microedition.io.*;
import java.io.*;

public class HttpGetData extends MIDlet implements CommandListener {
	private Form form;
	private TextField tfURL;
	private Display display;
	private Command cmdExit;
	private Command cmdConnect;
	private void myInit() {
		cmdExit = new Command("Exit", Command.EXIT, 0);
		cmdConnect = new Command("Conn", Command.SCREEN, 1);
		tfURL = new TextField("Please Input URL",
				"http://www.google.com", 80, TextField.URL);
		form = new Form("Httpconnection GET test");
		form.append(tfURL);
		form.addCommand(cmdExit);
		form.addCommand(cmdConnect);
		form.setCommandListener(this);
	}

	public HttpGetData() {
		display = Display.getDisplay(this);
		myInit();
	}

	protected void destroyApp(boolean arg0) throws MIDletStateChangeException {
	}

	protected void pauseApp() {
	}

	protected void startApp() throws MIDletStateChangeException {
		display.setCurrent(form);
	}

	private void out(String msg) {
		// System.out.print(msg);
		form.append(msg);
	}

	private String requestGet(String url) {
		HttpConnection hpc = null;
		DataInputStream dis = null;
		String content = "";
		try {
			hpc = (HttpConnection) Connector.open(url);
			out("创建HttpConnection成功\n");
			hpc.setRequestMethod(HttpConnection.GET);
			out("setRequestMethod成功\n");
			dis = new DataInputStream(hpc.openInputStream());
			out("打开InputStream成功\n");
			if (hpc.getResponseCode() == HttpConnection.HTTP_OK) {
				int character;
				out("正在读取数据...\n");
				while ((character = dis.read()) != -1) {
					content += (char) character;
				}
			}
		} catch (IOException err) {
			out("读取数据发生异常：" + err.toString());
		} finally {
			if (hpc != null) {
				try {
					hpc.close();
				} catch (Exception e) {

				}
				hpc = null;
			}
			if (dis != null) {
				try {
					dis.close();
				} catch (Exception e) {
				}
				dis = null;
			}
		}
		content = (unicodeTogb2312(content)).trim();
		return content;
	}

	private String unicodeTogb2312(String s) {
		if (s == null) {
			return "";
		}
		if (s.equals("")) {
			return s;
		}
		try {
			return new String(s.getBytes("ISO8859_1"), "gb2312");
		} catch (Exception err) {
			return s;
		}
	}

	public void commandAction(Command c, Displayable s) {
		if (c == cmdExit) {
			try {
				destroyApp(true);
			} catch (Exception err) {
			}
		} else if (c == cmdConnect) {
			try {
				String url = tfURL.getString();
				if (!url.startsWith("http://"))
					url = "http://" + url;
				String ret = requestGet(url);
				out(ret);
			} catch (Exception err) {
				form.append("发生异常：" + err.toString());
			}
		}
	}

}