Getting cannot find symbol error compiling java code using NetBeans 6.5 IDE

rstewart · 02-13-2009, 02:17 PM

Hi folks,

I am a java newby, need to implement a project for work using java, and am getting a compiler error that I don't understand the reason for.

Here is the error from the compiler:

Code:

symbol  : method read(byte[],int,int)
location: class java.io.BufferedReader
        oStreamIn.read( sRxBuf, 0, sRxBuf.length );
1 error
BUILD FAILED (total time: 0 seconds)

I am trying to use the BufferedReader class to read in some data from a socket into a predefined byte array. Below is the relavent code:

Code:

import java.net.*;
import java.io.*;
import java.util.logging.Level;
import java.util.logging.Logger;

public class CommInterface {
     private Socket oSocketFD = null;
     private PrintWriter oStreamOut = null;
     private BufferedReader oStreamIn = null;
     private byte[] sRxBuf = new byte[2048];

     private int receiveServerMsg()
     {
          .
          .
          .
          // Attempt to receive a message from the server
          oStreamIn.read( sRxBuf, 0, sRxBuf.length );
          .
          .
          .
          // And return
          return( 0 );
     }

     public int openConnectionToServer( String sServer, int nPort )
     {
        //  Attempt to connect and log in to the server
        try
        {
             oSocketFD = new Socket( sServer, nPort );
             oStreamOut = new PrintWriter( oSocketFD.getOutputStream(), true );
             oStreamIn = new BufferedReader( new InputStreamReader(oSocketFD.getInputStream()) );
        }
        catch (UnknownHostException e)
        {
             oSocketFD = null;
             oStreamOut = null;
             oStreamIn = null;
             System.err.println( "Don't know about host: " + sLMCSServer );
             System.exit( 1 );
        }
        catch (IOException e)
        {
             oSocketFD = null;
             oStreamOut = null;
             oStreamIn = null;
             System.err.println( "Couldn't get I/O for the connection to: " + sLMCSServer );
             System.exit( 1 );
        }

        //  And return
        return( 0 );
    }
}

The compilation error occurs on the "oStreamIn.read( sRxBuf, 0, sRxBuf.length );" line.

I have googled for various "cannot find symbol" java compilation error messages but I don't seem to be able to see anything that makes sense in my context (probably due to my lack of java experience).

I would welcome any suggestions anyone can offer to try and explain to me why the error is being generated, and how to resolve it.

paulsm4 · 02-13-2009, 04:43 PM

Hi -

I think what the compiler really means is "parameter mismatch".

Specifically, here's the method:

Quote:

int read(char[] cbuf, int off, int len)
Read characters into a portion of an array.

To use it, you should declare "char[] sRxBuf = new char[2048];" (instead of "byte").

Of course, that might cause other problems.

One way around it is to use "InputStream" (which supports a "read" from a byte array).

I'd also recommand looking into "FileChannel" I/O, in the separate "java.nio" package:
http://www.java2s.com/Code/JavaAPI/j...eBufferbuf.htm

'Hope that helps .. PSM