IO demo: DataOutputStream and DataInputStream
import java.io.DataInputStream; import java.io.DataOutputStream; import java.io.EOFException; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; public class DataIODemo1 { public static void main(String[] args) throws IOException { DataOutputStream out = new DataOutputStream(new FileOutputStream( "Java2s.txt")); double[] prices = { 19.99, 9.99, 15.99, 3.99, 4.99 }; int[] units = { 12, 8, 13, 29, 50 }; String[] descs = { "Java", "Source ", "and", "Support."}; for (int i = 0; i < prices.length; i++) { out.writeDouble(prices[i]); out.writeChar('\t'); out.writeInt(units[i]); out.writeChar('\t'); out.writeChars(descs[i]); out.writeChar('\n'); } out.close(); // read it in again DataInputStream in = new DataInputStream(new FileInputStream( "Java2s.txt")); double price; int unit; String desc; double total = 0.0; try { while (true) { price = in.readDouble(); in.readChar(); // throws out the tab unit = in.readInt(); in.readChar(); // throws out the tab desc = in.readLine(); System.out.println( unit ); System.out.println( desc ); System.out.println( desc ); total = total + unit * price; } } catch (EOFException e) { } in.close(); } }