TestLittleEndian.java
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this work for additional information regarding copyright ownership.
The ASF licenses this file to You under the Apache License, Version 2.0
(the "License"); you may not use this file except in compliance with
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package org.apache.poi.util;
import static org.junit.jupiter.api.Assertions.assertArrayEquals;
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertThrows;
import static org.junit.jupiter.api.Assertions.assertTrue;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import org.apache.poi.util.LittleEndian.BufferUnderrunException;
import org.junit.jupiter.api.Test;
/**
* Class to test LittleEndian functionality
*/
final class TestLittleEndian {
/**
* test the getShort() method
*/
@Test
void testGetShort() {
byte[] testdata = new byte[ LittleEndianConsts.SHORT_SIZE + 1 ];
testdata[0] = 0x01;
testdata[1] = (byte) 0xFF;
testdata[2] = 0x02;
short[] expected = new short[2];
expected[0] = ( short ) 0xFF01;
expected[1] = 0x02FF;
assertEquals(expected[0], LittleEndian.getShort(testdata));
assertEquals(expected[1], LittleEndian.getShort(testdata, 1));
}
@Test
void testGetUShort() {
byte[] testdata = {
(byte) 0x01,
(byte) 0xFF,
(byte) 0x02,
};
byte[] testdata2 = {
(byte) 0x0D,
(byte) 0x93,
(byte) 0xFF,
};
int expected0 = 0xFF01;
int expected1 = 0x02FF;
int expected2 = 0x930D;
int expected3 = 0xFF93;
assertEquals(expected0, LittleEndian.getUShort(testdata));
assertEquals(expected1, LittleEndian.getUShort(testdata, 1));
assertEquals(expected2, LittleEndian.getUShort(testdata2));
assertEquals(expected3, LittleEndian.getUShort(testdata2, 1));
byte[] testdata3 = new byte[ LittleEndianConsts.SHORT_SIZE + 1 ];
LittleEndian.putUShort(testdata3, 0, expected2);
LittleEndian.putUShort(testdata3, 1, expected3);
assertEquals(0x0D, testdata3[0]);
assertEquals((byte)0x93, testdata3[1]);
assertEquals((byte)0xFF, testdata3[2]);
assertEquals(expected2, LittleEndian.getUShort(testdata3));
assertEquals(expected3, LittleEndian.getUShort(testdata3, 1));
}
private static final byte[] _double_array =
{
56, 50, -113, -4, -63, -64, -13, 63, 76, -32, -42, -35, 60, -43, 3, 64
};
/** 0x7ff8000000000000 encoded in little endian order */
private static final byte[] _nan_double_array = HexRead.readFromString("00 00 00 00 00 00 F8 7F");
private static final double[] _doubles =
{
1.23456, 2.47912, Double.NaN
};
/**
* test the getDouble() method
*/
@Test
void testGetDouble() {
assertEquals(_doubles[0], LittleEndian.getDouble(_double_array, 0), 0.000001 );
assertEquals(_doubles[1], LittleEndian.getDouble( _double_array, LittleEndianConsts.DOUBLE_SIZE), 0.000001);
assertTrue(Double.isNaN(LittleEndian.getDouble(_nan_double_array, 0)));
double nan = LittleEndian.getDouble(_nan_double_array, 0);
byte[] data = new byte[8];
LittleEndian.putDouble(data, 0, nan);
assertArrayEquals(data, _nan_double_array);
}
/**
* test the getInt() method
*/
@Test
void testGetInt() {
// reading 4 byte data from a 5 byte buffer
byte[] testdata = {
(byte) 0x01,
(byte) 0xFF,
(byte) 0xFF,
(byte) 0xFF,
(byte) 0x02,
};
assertEquals(0xFFFFFF01, LittleEndian.getInt(testdata));
assertEquals(0x02FFFFFF, LittleEndian.getInt(testdata, 1));
}
/**
* test the getLong method
*/
@Test
void testGetLong() {
// reading 8 byte values from a 9 byte buffer
byte[] testdata = {
(byte) 0x01,
(byte) 0xFF,
(byte) 0xFF,
(byte) 0xFF,
(byte) 0xFF,
(byte) 0xFF,
(byte) 0xFF,
(byte) 0xFF,
(byte) 0x02,
};
assertEquals(0xFFFFFFFFFFFFFF01L, LittleEndian.getLong(testdata, 0));
assertEquals(0x02FFFFFFFFFFFFFFL, LittleEndian.getLong(testdata, 1));
}
/**
* test the PutShort method
*/
@Test
void testPutShort() {
byte[] expected = new byte[ LittleEndianConsts.SHORT_SIZE + 1 ];
expected[0] = 0x01;
expected[1] = (byte) 0xFF;
expected[2] = 0x02;
byte[] received = new byte[ LittleEndianConsts.SHORT_SIZE + 1 ];
short[] testdata = new short[2];
testdata[0] = ( short ) 0xFF01;
testdata[1] = 0x02FF;
LittleEndian.putShort(received, 0, testdata[0]);
assertTrue(compareByteArrays(received, expected, 0, LittleEndianConsts.SHORT_SIZE));
LittleEndian.putShort(received, 1, testdata[1]);
assertTrue(compareByteArrays(received, expected, 1, LittleEndianConsts.SHORT_SIZE));
}
/**
* test the putInt method
*/
@Test
void testPutInt() {
// writing 4 byte data to a 5 byte buffer
byte[] expected = {
(byte) 0x01,
(byte) 0xFF,
(byte) 0xFF,
(byte) 0xFF,
(byte) 0x02,
};
byte[] received = new byte[ LittleEndianConsts.INT_SIZE + 1 ];
LittleEndian.putInt(received, 0, 0xFFFFFF01);
assertTrue(compareByteArrays(received, expected, 0, LittleEndianConsts.INT_SIZE));
LittleEndian.putInt(received, 1, 0x02FFFFFF);
assertTrue(compareByteArrays(received, expected, 1, LittleEndianConsts.INT_SIZE));
}
/**
* test the putDouble methods
*/
@Test
void testPutDouble() {
byte[] received = new byte[ LittleEndianConsts.DOUBLE_SIZE + 1 ];
LittleEndian.putDouble(received, 0, _doubles[0]);
assertTrue(compareByteArrays(received, _double_array, 0, LittleEndianConsts.DOUBLE_SIZE));
LittleEndian.putDouble(received, 1, _doubles[1]);
byte[] expected = new byte[ LittleEndianConsts.DOUBLE_SIZE + 1 ];
System.arraycopy(_double_array, LittleEndianConsts.DOUBLE_SIZE, expected,
1, LittleEndianConsts.DOUBLE_SIZE);
assertTrue(compareByteArrays(received, expected, 1, LittleEndianConsts.DOUBLE_SIZE));
}
/**
* test the putLong method
*/
@Test
void testPutLong() {
// writing 8 byte values to a 9 byte buffer
byte[] expected = {
(byte) 0x01,
(byte) 0xFF,
(byte) 0xFF,
(byte) 0xFF,
(byte) 0xFF,
(byte) 0xFF,
(byte) 0xFF,
(byte) 0xFF,
(byte) 0x02,
};
byte[] received = new byte[ LittleEndianConsts.LONG_SIZE + 1 ];
long testdata0 = 0xFFFFFFFFFFFFFF01L;
long testdata1 = 0x02FFFFFFFFFFFFFFL;
LittleEndian.putLong(received, 0, testdata0);
assertTrue(compareByteArrays(received, expected, 0, LittleEndianConsts.LONG_SIZE));
LittleEndian.putLong(received, 1, testdata1);
assertTrue(compareByteArrays(received, expected, 1, LittleEndianConsts.LONG_SIZE));
}
private static final byte[] _good_array = {
0x01, 0x02, 0x01, 0x02,
0x01, 0x02, 0x01, 0x02,
0x01, 0x02, 0x01, 0x02,
0x01, 0x02, 0x01, 0x02,
};
private static final byte[] _bad_array = {
0x01
};
/**
* test the readShort method
*/
@Test
void testReadShort() throws IOException {
short expected_value = 0x0201;
InputStream stream = new ByteArrayInputStream(_good_array);
int count = 0;
while (true) {
try {
short value = LittleEndian.readShort(stream);
assertEquals(value, expected_value);
count++;
} catch (BufferUnderrunException e) {
break;
}
}
assertEquals(count,
_good_array.length / LittleEndianConsts.SHORT_SIZE);
ByteArrayInputStream stream2 = new ByteArrayInputStream(_bad_array);
assertThrows(BufferUnderrunException.class, () -> LittleEndian.readShort(stream2));
}
/**
* test the readInt method
*/
@Test
void testReadInt() throws IOException {
int expected_value = 0x02010201;
InputStream stream = new ByteArrayInputStream(_good_array);
int count = 0;
while (true) {
try {
int value = LittleEndian.readInt(stream);
assertEquals(value, expected_value);
count++;
} catch (BufferUnderrunException e) {
break;
}
}
assertEquals(count, _good_array.length / LittleEndianConsts.INT_SIZE);
ByteArrayInputStream stream2 = new ByteArrayInputStream(_bad_array);
assertThrows(BufferUnderrunException.class, () -> LittleEndian.readInt(stream2));
}
/**
* test the readLong method
*/
@Test
void testReadLong() throws IOException {
long expected_value = 0x0201020102010201L;
InputStream stream = new ByteArrayInputStream(_good_array);
int count = 0;
while (true) {
try {
long value = LittleEndian.readLong(stream);
assertEquals(value, expected_value);
count++;
} catch (BufferUnderrunException e) {
break;
}
}
assertEquals(count, _good_array.length / LittleEndianConsts.LONG_SIZE);
ByteArrayInputStream stream2 = new ByteArrayInputStream(_bad_array);
assertThrows(BufferUnderrunException.class, () -> LittleEndian.readLong(stream2));
}
@Test
void testReadFromStream() throws IOException {
int actual;
actual = LittleEndian.readUShort(new ByteArrayInputStream(new byte[] { 5, -128, }));
assertEquals(32773, actual);
actual = LittleEndian.readUShort(new ByteArrayInputStream(new byte[] { 1, 2, 3, 4, }));
assertEquals(513, actual);
assertThrows(BufferUnderrunException.class, () ->
LittleEndian.readInt(new ByteArrayInputStream(new byte[] { 1, 2, 3, })));
}
@Test
void testUnsignedByteToInt() {
assertEquals(255, LittleEndian.ubyteToInt((byte)255));
}
private static boolean compareByteArrays(byte [] received, byte [] expected,
int offset, int size) {
for (int j = offset; j < offset + size; j++) {
if (received[j] != expected[j]) {
System.out.println("difference at index " + j);
return false;
}
}
return true;
}
@Test
void testUnsignedShort() {
assertEquals(0xffff, LittleEndian.getUShort(new byte[] { (byte)0xff, (byte)0xff }, 0));
}
}