Random Access Files

[jambeard lewistrix]

I've just started using random access files and need to know what i'm doing wrong.

I've made a test program (just to learn how to work with them) but it dosn't work properlly.

The first part of the program reads in names entered by the user and should work like this:

read in name from user
write to file
repeat until user exits
then add '.' to the end of the file

Then the second reads in the values like this:

read in name
display name
repeat this until '.' char found

The first part of the program definately works. The names get entered and stored in the file and the '.' char gets added to the end of the file.

The second part of the program does not work. If I only enter 1 name in the first program then the second program works, but if I enter more than 1 name then it loops forever outputting null as the name.

This is my code for reading in the names:

public static void showData( RandomAccessFile file )
{

int i = 0;
boolean stop = false;

System.out.println( "This is the contents of the file:" );

while( true )
{

System.out.println( getNameNumber( file ) + ", " + getName( file ) );

if( endOfFile( file ) ) break;

}

}

public static int getNameNumber( RandomAccessFile file )
{

int nameNumber = 0;

try
{

nameNumber = file.readInt();

return nameNumber;

}
catch( IOException e ) {}

return nameNumber;

}

public static String getName( RandomAccessFile file )
{

char nameArray[] = new char[ 15 ], temp;

String nameString = null;

try
{

for( int j = 0; j < 15; j++ )
{

temp = file.readChar();
nameArray[j] = temp;

}

nameString = new String( nameArray ).replace( '\0',' ' );

return nameString;

}
catch( IOException e ) {}

return nameString;
 
}

public static boolean endOfFile( RandomAccessFile file )
{

char endChar;

try
{

endChar = file.readChar();
if( endChar == '.' ) return true;

}
catch( IOException e ) {}

return false;

}

Ignore the empty catch statements as this was just a quick test. Also, there's an int called nameNumber in there which is just a number assigned to the name when it is entered in program 1.

Can anyone see what i've done worng?

Cheers,

J

[Norm Radder]

In case no one sees your problem, I'd suggest you try debugging it yourself.
Add some println() statements to the code to show where it is and what the values are. This can be an iterative process while you narrow it down.
How to debug a program is a useful technique to know.