// Copyright 2001, FreeHEP.
package org.freehep.util.io;
import java.io.DataInput;
import java.io.DataInputStream;
import java.io.EOFException;
import java.io.IOException;
import java.io.InputStream;
/**
* Class to read bytes and pairs of bytes in both little and big endian order.
*
* @author Mark Donszelmann
* @author Charles Loomis
* @version $Id: ByteOrderInputStream.java,v 1.3 2008-05-04 12:21:49 murkle Exp
* $
*/
public class ByteOrderInputStream extends BitInputStream implements DataInput {
protected boolean little;
/**
* Create a byte order (big-endian) input stream from given stream.
*
* @param in
* stream to read from
*/
public ByteOrderInputStream(InputStream in) {
this(in, false);
}
/**
* Create a byte order input stream from given stream.
*
* @param in
* stream to read from
* @param littleEndian
* true if stream should be little endian.
*/
public ByteOrderInputStream(InputStream in, boolean littleEndian) {
super(in);
little = littleEndian;
}
@Override
public void readFully(byte b[]) throws IOException {
readFully(b, 0, b.length);
}
@Override
public void readFully(byte b[], int off, int len) throws IOException {
if (len < 0) {
throw new IndexOutOfBoundsException();
}
int n = 0;
while (n < len) {
int count = read(b, off + n, len - n);
if (count < 0) {
throw new EOFException();
}
n += count;
}
}
@Override
public int skipBytes(int n) throws IOException {
int total = 0;
int cur = 0;
while ((total < n) && ((cur = (int) skip(n - total)) > 0)) {
total += cur;
}
return total;
}
@Override
public boolean readBoolean() throws IOException {
int b = readUnsignedByte();
return (b != 0);
}
@Override
public char readChar() throws IOException {
int b1 = readUnsignedByte();
int b2 = readUnsignedByte();
return (little) ? (char) ((b1 << 8) + b2) : (char) ((b2 << 8) + b1);
}
/**
* Read a signed byte.
*/
@Override
public byte readByte() throws IOException {
byteAlign();
int b = read();
if (b < 0) {
throw new EOFException();
}
return (byte) b;
}
/**
* Read n bytes and return in byte array.
*
* @param n
* number of bytes to read
* @return byte array
* @throws IOException
* if read fails
*/
public byte[] readByte(int n) throws IOException {
byteAlign();
byte[] bytes = new byte[n];
for (int i = 0; i < n; i++) {
int b = read();
if (b < 0) {
throw new EOFException();
}
bytes[i] = (byte) b;
}
return bytes;
}
/**
* Read an unsigned byte.
*/
@Override
public int readUnsignedByte() throws IOException {
byteAlign();
int ub = read();
if (ub < 0) {
throw new EOFException();
}
return ub;
}
/**
* Read n unsigned bytes and return in int array.
*
* @param n
* number of bytes to read
* @return int array
* @throws IOException
* if read fails
*/
public int[] readUnsignedByte(int n) throws IOException {
byteAlign();
int[] bytes = new int[n];
for (int i = 0; i < n; i++) {
int ub = read();
if (ub < 0) {
throw new EOFException();
}
bytes[i] = ub;
}
return bytes;
}
/**
* Read a signed short.
*/
@Override
public short readShort() throws IOException {
int i1 = readUnsignedByte();
int i2 = readUnsignedByte();
return (little) ? (short) ((i2 << 8) + i1) : (short) ((i1 << 8) + i2);
}
/**
* Read n shorts and return in short array
*
* @param n
* number of shorts to read
* @return short array
* @throws IOException
* if read fails
*/
public short[] readShort(int n) throws IOException {
short[] shorts = new short[n];
for (int i = 0; i < n; i++) {
shorts[i] = readShort();
}
return shorts;
}
/**
* Read an unsigned short.
*/
@Override
public int readUnsignedShort() throws IOException {
byteAlign();
int i1 = readUnsignedByte();
int i2 = readUnsignedByte();
return (little) ? (i2 << 8) + i1 : (i1 << 8) + i2;
}
/**
* Read n unsigned shorts and return in int array
*
* @param n
* number of shorts to read
* @return int array
* @throws IOException
* if read fails
*/
public int[] readUnsignedShort(int n) throws IOException {
int[] shorts = new int[n];
for (int i = 0; i < n; i++) {
shorts[i] = readUnsignedShort();
}
return shorts;
}
/**
* Read a signed integer.
*/
@Override
public int readInt() throws IOException {
int i1 = readUnsignedByte();
int i2 = readUnsignedByte();
int i3 = readUnsignedByte();
int i4 = readUnsignedByte();
return (little) ? (i4 << 24) + (i3 << 16) + (i2 << 8) + i1
: (i1 << 24) + (i2 << 16) + (i3 << 8) + i4;
}
/**
* Read n ints and return in int array.
*
* @param n
* number of ints to read
* @return int array
* @throws IOException
* if read fails
*/
public int[] readInt(int n) throws IOException {
int[] ints = new int[n];
for (int i = 0; i < n; i++) {
ints[i] = readInt();
}
return ints;
}
/**
* Read an unsigned integer.
*
* @return long
* @throws IOException
* if read fails
*/
public long readUnsignedInt() throws IOException {
long i1 = readUnsignedByte();
long i2 = readUnsignedByte();
long i3 = readUnsignedByte();
long i4 = readUnsignedByte();
return (little) ? (i4 << 24) + (i3 << 16) + (i2 << 8) + i1
: (i1 << 24) + (i2 << 16) + (i3 << 8) + i4;
}
/**
* Read n unsigned ints and return in long array.
*
* @param n
* number of ints to read
* @return long array
* @throws IOException
* if read fails
*/
public long[] readUnsignedInt(int n) throws IOException {
long[] ints = new long[n];
for (int i = 0; i < n; i++) {
ints[i] = readUnsignedInt();
}
return ints;
}
@Override
public long readLong() throws IOException {
long i1 = readInt();
long i2 = readInt();
return (little) ? (i2 << 32) + (i1 & 0xFFFFFFFFL)
: (i1 << 32) + (i2 & 0xFFFFFFFFL);
}
@Override
public float readFloat() throws IOException {
return Float.intBitsToFloat(readInt());
}
@Override
public double readDouble() throws IOException {
return Double.longBitsToDouble(readLong());
}
/**
*/
@Override
public String readLine() throws IOException {
throw new IOException(
"ByteOrderInputStream.readLine() is not implemented.");
}
/**
* Read a string (UTF).
*
* @return string
* @throws IOException
* if read fails
*/
public String readString() throws IOException {
return readUTF();
}
@Override
public String readUTF() throws IOException {
return DataInputStream.readUTF(this);
}
/**
* Read an ascii-z (0 terminated c-string).
*
* @return string
* @throws IOException
* if read fails
*/
public String readAsciiZString() throws IOException {
StringBuffer buffer = new StringBuffer();
char c = (char) readUnsignedByte();
while (c != 0) {
buffer.append(c);
c = (char) readUnsignedByte();
}
return buffer.toString();
}
}