httpconnectiondemo.java

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import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import javax.microedition.io.* ;
import java.io.*;
public class HttpConnectionDemo extends MIDlet
	implements CommandListener
{
	String url = "http://localhost/HttpConnectionDemo.asp" ;

	Form mainForm = new Form ("HttpConnectionDemo");
	TextField nameField = 
		new TextField ("姓名", "唐先生", 15, TextField.ANY);
	TextField ageField = 
		new TextField ("年龄", "18", 5, TextField.NUMERIC);
	StringItem resultItem = 
		new StringItem ("", "");
	Command getCmd = 
		new Command ("Get", Command.SCREEN, 1);
	Command postCmd = 
		new Command ("Post", Command.SCREEN, 0);
	Command exitCmd = 
		new Command ("Exit", Command.EXIT, 0);

	public HttpConnectionDemo () {
		mainForm.append (nameField);
		mainForm.append (ageField);
		mainForm.append (resultItem);
		mainForm.addCommand (getCmd);
		mainForm.addCommand (postCmd);
		mainForm.addCommand (exitCmd);
		mainForm.setCommandListener (this);
	}

	public void startApp()
	{
		Display.getDisplay (this).setCurrent (mainForm);
		try{
			getDemo( nameField.getString(), ageField.getString()  );
		}catch(Exception e)
		{
			System.out.println( e );
		}
	}

	// 使用GET方式
	void getDemo(String name, String age) throws Exception 
	{
		HttpConnection c = null;

		try 
		{
			String query = "name=" + name;
			query += "&" + "age=" + age;

			c = (HttpConnection)Connector.open(
				url + "?" + query );

			c.setRequestMethod(HttpConnection.GET);
			
			readFromWeb( c );

		}
		catch (ClassCastException e) 
		{
			throw new IllegalArgumentException("Not an HTTP URL");
		}
	}

	// 使用POST方式
	void postDemo(String name, String age) throws Exception 
	{
		String info = "name=" + name;
		info += "&" + "age=" + age;

		HttpConnection c = null;
		OutputStream os = null;
		try 
		{
			c = (HttpConnection)Connector.open(url);

			c.setRequestMethod(HttpConnection.POST);
			
			c.setRequestProperty("CONTENT-TYPE",
				"application/x-www-form-urlencoded");

			os = c.openOutputStream();

			byte [] data = info.getBytes("GB2312");
			for( int i=0; i<data.length; i++ ) 
				os.write( (byte) data[i] );

			readFromWeb( c );

		}
		catch (ClassCastException e) 
		{
			throw new IllegalArgumentException("Not an HTTP URL");
		}
	}


	// 获取从服务器返回的结果
	void readFromWeb( HttpConnection c ) throws Exception
	{
		InputStream is = null;
		try
		{
			int rc = c.getResponseCode();
			if (rc != HttpConnection.HTTP_OK) 
			{
				//throw new Exception("HTTP response code: " + rc);
			}
			System.out.println( rc );

			is = c.openInputStream();

			String type = c.getType();
			System.out.println( type );

			int len = (int)c.getLength();
			System.out.println( len );
			if (len > 0) 
			{
				int actual = 0;
				int bytesread = 0 ;
				byte[] data = new byte[len];
				while ((bytesread != len) && (actual != -1)) 
				{
					actual = is.read(
						data, bytesread, len - bytesread);
					bytesread += actual;
				}
				process(data);
			} 
			else 
			{
				int ch;
				while ((ch = is.read()) != -1) 
				{
					process((byte)ch);
				}
			}
		} 
		finally 
		{
			if (is != null)
				is.close();
		}
	}

	void process(byte[] data)
	{
		String str = "";
		try{
			str = new String(data, "GB2312");
		}
		catch(java.io.UnsupportedEncodingException e )
		{
			System.out.println( e );
		}

		System.out.println( str );
		resultItem.setText( str );
	}

	void process(byte ch)
	{
		resultItem.setText( resultItem.getText() + (char) ch );
	}

	public void pauseApp()
	{}
	public void destroyApp(boolean unconditional)
	{}

	public void commandAction(javax.microedition.lcdui.Command c,
		javax.microedition.lcdui.Displayable d) 
	{
		try
		{
			if(c.equals(getCmd))
			{
				Object cSR;
				getDemo( 
					nameField.getString(), ageField.getString() );
			}
			else if(c.equals(postCmd))
			{
				postDemo( 
					nameField.getString(), ageField.getString() );
			}

			else if(c.equals(exitCmd))
			{
				destroyApp(false);
				notifyDestroyed();
			}
		}
		catch (Exception e)
		{
			e.printStackTrace();
			resultItem.setLabel("Error: " + e);
			System.out.println(e);
		}
	}

}