"System cannot find the path specified" error message !HELP !

Question

Hi
In doing a program to read a string from the buffer, I am getting an error message that says "cannot find the file specified"
The file was created in a previous program and I verified it does
exist at the specified location on my hard disk.
Below is the "ReadAString" program and "WriteAString" program where the String was created.
Thanks
Joe
import java.io.*;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
public class ReadAString
public static void main(String[] args)
File myFile = new File("C:Documents and Settings/Gateway User/jbproject/ssd_ch10p407/src/ssd_ch10p407/charData.txt");
FileInputStream myInputFileInAStream = null;
try
myInputFileInAStream = new FileInputStream(myFile);
catch (FileNotFoundException e)
e.printStackTrace();
System.exit(1);
FileChannel myInputChannel = myInputFileInAStream.getChannel();
ByteBuffer myByteBuffer = ByteBuffer.allocate(48);
System.out.println("\nNew buffer: \tposition = " +
myByteBuffer.position() + "\tLimit = " +
myByteBuffer.limit() + " \tcapacity = " +
myByteBuffer.capacity());
try
//size() will return the length of the file
System.out.println("\nFile contains " + myInputChannel.size() + " bytes");
//The FileChannel object keeps track of the file's current position
System.out.println(
"The file's current position before the read into the buffer is: " +
myInputChannel.position());
while (myInputChannel.read(myByteBuffer) != -1)
System.out.println("\nBuffer after read: \tposition = " +
myByteBuffer.position() + "\tLimit = " +
myByteBuffer.limit() + " \tcapacity = " +
myByteBuffer.capacity());
System.out.println(
"The file's current position after it read into the buffer is: " +
myInputChannel.position());
System.out.println("\nString read: " +
( (ByteBuffer) (myByteBuffer.flip())).asCharBuffer().
toString());
System.out.println("Buffer after flip: \tposition = " +
myByteBuffer.position() + "\tLimit = " +
myByteBuffer.limit() + " \tcapacity = " +
myByteBuffer.capacity());
// set the limit to capacity and the position to 0
myByteBuffer.clear(); //clear the buffer for the next read
} //end of while loop
System.out.println("\nEOF reached.");
myInputFileInAStream.close(); //close the file and the channel
catch (IOException e) {
e.printStackTrace(System.err);
System.exit(1);
System.exit(0);
import java.io.*;
import java.nio.*;
import java.nio.channels.FileChannel;
//This program takes a text phrase (in Unicode characters;(2 bytes each character)
//and puts it into a buffer via a CharBuffer,
//then loads the buffer contents into a file channel
//then outputs to a file.
//When you have successfully run the program, go to Start | Search |
//type in "charData.txt" and examine the contents of the file. OR
//go to the notepad and open
// C:
//Documents and Settings
//GateWay User
//jbproject
//ssd_ch10p407
//src
//ssd_ch10p407
//you should see charData so right click on it and choose "open with " "Notepad"
// and verify the contents are "Garbage in Garbage out"
// each time you run the program, "Garbage in Garbage out " should be concatenated.
public class WriteAString
public static void main(String[] args)
String phrase = new String("Garbage in Garbage out\n");
String dirname = "C:/Documents and Settings/Gateway User/jbproject/ssd_ch10p407/src/ssd_ch10p407";
String filename = "charData.txt";
File dir = new File(dirname);
//now checkout the directory
if (!dir.exists()) {
if (!dir.mkdir()) { //.....create it
System.out.println("Cannot create directory: " + dirname);
System.exit(1);
else if (!dir.isDirectory()) {
System.err.println(dirname + " is not a directory");
System.exit(1);
//create the fielstream
File myFile = new File(dir, filename);
FileOutputStream myOutputFileInAStream = null; //place to store the stream reference
try
myOutputFileInAStream = new FileOutputStream(myFile, true);
System.out.println("File stream created successfully");
catch (FileNotFoundException e)
e.printStackTrace(System.err);
ByteBuffer myByteBuffer = ByteBuffer.allocate(1024); //ByteBuffer object created
CharBuffer myCharBuffer = myByteBuffer.asCharBuffer(); // create view buffer
//transfer the phrase to myByteBuffer via mycharBuffer
myCharBuffer.put(phrase);
//update myByteBuffer limit (position times 2 because each Unicode
// character takes 2 bytes) to store in the ByteBuffer
myByteBuffer.limit(2 * myCharBuffer.position());
System.out.println("myCharBuffer position is " + myCharBuffer.position());
//create the file output stream channel object
FileChannel myOutputChannel = myOutputFileInAStream.getChannel();
System.out.println("new buffer: position = " +
myByteBuffer.position() +
"\tLimit = " + myByteBuffer.limit() +
" \tcapacity = " + myByteBuffer.capacity());
//each time the program is run, the phrase is again loaded into the buffer.
// Run the program several times and open charData.txt to verify that the
//data went into the file.
//Load the data into the buffer
for (int i = 0; i < phrase.length(); i++)
myByteBuffer.putChar(phrase.charAt(i));
System.out.println("Buffer after loading : position = " +
myByteBuffer.position() + "\tLimit = " +
myByteBuffer.limit() + " \tcapacity = " +
myByteBuffer.capacity());
myByteBuffer.flip(); //flip the buffer ready for file write
System.out.println("Buffer after flip: position = " +
myByteBuffer.position() + "\tLimit = " +
myByteBuffer.limit() + " \tcapacity = " +
myByteBuffer.capacity());
//write this file
try
myOutputChannel.write(myByteBuffer); //write the buffer to the file channel
System.out.println("The file contains " + myOutputChannel.size() + " bytes" +
" Do you see this number double every time you run the program?");
//you should see 48 characters writen to the file each time (phrase has 24 characters)
myOutputFileInAStream.close(); //close the output stream and channel
System.out.println("Buffer contents written to file");
catch(IOException e)
e.printStackTrace(System.err);
System.exit(0);
//After running the program once my output was:
//File stream created successfully
//myCharBuffer position is 23
//new buffer: position = 0     Limit = 46      capacity = 1024
//Buffer after loading : position = 46     Limit = 46      capacity = 1024
//Buffer after flip: position = 0     Limit = 46      capacity = 1024
//The file contains 46 bytes //Do you see this number double every time you run the program?
//Buffer contents written to file

Answer 1

Right - File is smart. Otherwise, you'd have to build
platform-specific paths by hand, using file.seperator,
to keep your code multi-platform. Ew.
Grant
IC..
Aldaris84 bows his head in honour of the man/woman that created the clearly intelligate File class
:)