connector.java

j2me的数据库系统开发的经典案例

/**
 * 
 */
package connectpacket;

/**
 * @author Administrator
 *
 */
import javax.microedition.io.*;
import java.io.*;
import javax.microedition.lcdui.*;
public class Connector extends Form implements CommandListener{

	/**
	 * @param args
	 */
 
 private Command exitCommand;
 private Connector_MIDlet cm;
 private StringBuffer buf;
 private InputStream is;	
		// TODO 自动生成方法存根
 public Connector(Connector_MIDlet cm)
 {
	  super("Content_HttpConnection");
	   this.cm=cm;
	   buf=new StringBuffer();


	   exitCommand=new Command("Exit",Command.EXIT,1);
	   this.addCommand(exitCommand);
	   this.setCommandListener(this);
				try
				{
					//定义一个URL
					String str_url="http://127.0.0.1:8086/default.htm";
					System.out.println(str_url);
					//定义一个ContentConnection 
					HttpConnection con=(HttpConnection) javax.microedition.io.Connector.open(str_url);
					
					System.out.println(con);
					int state=con.getResponseCode();
					if(state==HttpConnection.HTTP_OK)
					{
					   is=con.openInputStream();
					}
					int ch=0;
					System.out.println("conType::"+con.getType());
					System.out.println("conCode::"+con.getEncoding());
					System.out.println("conLength::"+con.getLength());
					System.out.println("is.length::"+is.available());
					int tempLength=(int)con.getLength();
					 char bufChar[]=new char[tempLength];
					 InputStreamReader isr=new InputStreamReader(is);//运用包装类可以直接从字节输入流中读去字符
					  isr.read(bufChar,0,bufChar.length);
					  buf.append(String.valueOf(bufChar));
					  
					  
					/*while((ch=is.read())!=-1)
					{
						buf.append((char)ch);
						System.out.println((char)ch);
					}*/
				   this.append(buf.toString());
				  // System.out.print("buf.lenght::");
				  // System.out.println(buf.toString().trim().length());//出去字符串缓存区的前导和尾补空白,或者得到的字符个数
				   //会和buf的长度不一致,这是StringBuffer本身的属性找成的..
				  
					is.close();
					con.close();
					//UnsatisfiedLinkError: isNetworkMonitorActive
				}
				catch(javax.microedition.io.ConnectionNotFoundException e)
				{
					System.out.println("urlCould not be foud");
					
				}
				catch(IOException ex)
				{
					System.out.println(ex.toString());
				}
		

 }
 //定义响应按扭事件的函数
 public void commandAction(Command c,Displayable d)
 {
	 if(c==exitCommand)
	 {
		 cm.quitApp();
	 }
 }

}