Java IO.pdf - Nguyen Dang Binh

Java I/O
The FileOutputStream class has one method that's not declared in java.io.OutputStream,
getFD():
public final FileDescriptor getFD() throws IOException
This method returns the java.io.FileDescriptor object associated with this stream.
The FileOutputStream class also has a protected finalize() method that's invoked before
a FileOutputStream object is garbage-collected. This method ensures that files are properly
flushed and closed before the file output stream that opened them is garbage-collected. You
normally don't need to invoke this method explicitly. If you subclass FileOutputStream and
override finalize(), the subclass's finalize() method should invoke this finalize()
method by calling super.finalize().
Example 4.2 reads two filenames from the command line, then copies the first file into the
second file. The StreamCopier class from Example 3.3 in the last chapter is used to do the
actual reading and writing.
Example 4.2. The FileCopier Program
import java.io.*;
import com.macfaq.io.*;
public class FileCopier {
public static void main(String[] args) {
}
if (args.length != 2) {
System.err.println("Usage: java FileCopier infile outfile");
}
try {
copy(args[0], args[1]);
}
catch (IOException e) {System.err.println(e);}
public static void copy(String inFile, String outFile)
throws IOException {
FileInputStream fin = null;
FileOutputStream fout = null;
try {
fin = new FileInputStream(inFile);
fout = new FileOutputStream(outFile);
StreamCopier.copy(fin, fout);
}
finally {
try {
if (fin != null) fin.close();
}
catch (IOException e) {
}
try {
if (fout != null) fout.close();
}
catch (IOException e) { }
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