I am having trouble reading values from a binary file. The file is
written in LSB order but X10 assumes MSB order. I have written methods
to compensate for this. The methods for shorts, ints, and floats work,
but I'm having trouble with the longs and doubles. Here is a test case.
Can someone verify this?
import x10.io.*;
import x10.io.Console;
class ByteTester {
public static def main(args: Rail[String] ) {
val fileName = "double-x10file.bin";
write(fileName);
//prints two floats -1.2251404E-32, 2.597222
floatReader(2, fileName);
//should print double 1.111111100000000e+01 (or equiv)
doubleReader(1, fileName);
return;
}
static def floatReader(n :Int, fileName: String ){
var reader: FileReader;
var i: Int = 0;
try{
reader = new FileReader( new File(fileName) );
for ( i = 0; i < n; i++ ){
val value = getFloat(reader);
Console.OUT.println( " -->\t" + value );
}
reader.close();
}catch(e:Exception){
Console.OUT.println("OOOPS!!");
e.printStackTrace();
}
return i;
}
static def doubleReader(n :Int, fileName: String ){
var reader: FileReader;
var i: Int = 0;
try{
reader = new FileReader( new File(fileName) );
for ( i = 0; i < n; i++ ){
val value = getDouble(reader);
Console.OUT.println( " -->\t" + value );
}
reader.close();
}catch(e:Exception){
Console.OUT.println("OOOPS!!");
e.printStackTrace();
}
return i;
}
/*writes 8 bytes*/
public static def write(fileName: String){
try{
var writer:FileWriter = new FileWriter( new
File(fileName));
writer.writeByte(0xa3 as byte);
writer.writeByte(0x73 as byte);
writer.writeByte(0x7e as byte);
writer.writeByte(0x8a as byte);
writer.writeByte(0xe3 as byte);
writer.writeByte(0x38 as byte);
writer.writeByte(0x26 as byte);
writer.writeByte(0x40 as byte);
writer.close();
}catch(e:Exception){
Console.OUT.println("OOOPS!!");
e.printStackTrace();
}
}
/* reads 8 bytes in MSB and converts to LSB incorrectly */
static def getDouble( reader: FileReader ) : Double throws
IOException {
val byte0 = reader.read(); Console.OUT.printf(" %X\t", byte0);
val byte1 = reader.read(); Console.OUT.printf(" %X\t", byte1);
val byte2 = reader.read(); Console.OUT.printf(" %X\t", byte2);
val byte3 = reader.read(); Console.OUT.printf(" %X\t", byte3);
val byte4 = reader.read(); Console.OUT.printf(" %X\t", byte4);
val byte5 = reader.read(); Console.OUT.printf(" %X\t", byte5);
val byte6 = reader.read(); Console.OUT.printf(" %X\t", byte6);
val byte7 = reader.read(); Console.OUT.printf(" %X\t", byte7);
val ret1 = ( ((byte7&0xff)<<56) | ((byte6&0xff)<<48) |
((byte5&0xff)<<40) | ((byte4 & 0xff)<<32) );
val ret0 = ( ((byte3&0xff)<<24) | ((byte2&0xff)<<16) |
((byte1&0xff)<<8) | (byte0 & 0xff) );
return Double.fromLongBits((ret0|ret1) as Long);
}
/* reads 4 bytes in MSB and converts to LSB correctly */
static def getFloat( reader: FileReader ) :Float throws IOException {
val byte0 = reader.read(); Console.OUT.printf(" %X \t",byte0);
val byte1 = reader.read(); Console.OUT.printf(" %X \t",byte1);
val byte2 = reader.read(); Console.OUT.printf(" %X \t",byte2);
val byte3 = reader.read(); Console.OUT.printf(" %X \t",byte3);
val ret = ( ((byte3&0xff)<<24) | ((byte2&0xff)<<16) |
((byte1&0xff)<<8) | (byte0 & 0xff) );
return Float.fromIntBits(ret);
}
}
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