Menu
I am trying to read the number of line in a binary file using readObject, but I get IOException EOF. Am I doing this the right way?
FileInputStream istream = new FileInputStream(fileName); ObjectInputStream ois = new ObjectInputStream(istream); /** calculate number of items **/ int line_count = 0; while( (String)ois.readObject() != null){ line_count++; } 
858
close() method. After any operation to the file, we have to close that file.
The FileInputStream read() method throws a java. io. IOException if for some reason it can't read from the file. Again, the InputFile class makes no attempt to catch or declare this exception.
A FileInputStream obtains input bytes from a file in a file system. What files are available depends on the host environment. FileInputStream is meant for reading streams of raw bytes such as image data. For reading streams of characters, consider using FileReader .
readObject() doesn't return null at EOF. You could catch the EOFException and interpret it as EOF, but this would fail to detect distinguish a normal EOF from a file that has been truncated.
A better approach would be to use some meta-data. That is, rather than asking the ObjectInput how many objects are in the stream, you should store the count somewhere. For example, you could create a meta-data class that records the count and other meta-data and store an instance as the first object in each file. Or you could create a special EOF marker class and store an instance as the last object in each file.
175
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
