package pte.stone;
import java.io.ByteArrayInputStream;
import java.io.DataInputStream;
/**
* Converter between byte[] to hexadecimal String.
*
* @author stone
*
*/
public class ConverterBetweenHexStringAndByteArray {
/**
* Convert byte[] to hexadecimal String.
*
* @param bytea
* @return
* @throws Exception
*/
public static String byteArr2HexStr1(byte[] bytea) throws Exception {
String sHex = "";
DataInputStream dis = new DataInputStream(new ByteArrayInputStream(
bytea));
int iUnsigned = 0;
StringBuffer sbHex = new StringBuffer();
while (true) {
iUnsigned = dis.read();
if (iUnsigned == -1) {
break;
}
if (iUnsigned < 16) {
sbHex.append("0");
}
sbHex.append(Integer.toString(iUnsigned, 16));
}
sHex = sbHex.toString();
return sHex;
}
/**
* Convert byte[] to hexadecimal String.
*
* @param bytea
* @return
* @throws Exception
*/
public static String byteArr2HexStr2(byte[] bytea) throws Exception {
String sHex = "";
int iUnsigned = 0;
StringBuffer sbHex = new StringBuffer();
for (int i = 0; i < bytea.length; i++) {
iUnsigned = bytea[i];
if (iUnsigned < 0) {
iUnsigned += 256;
}
if (iUnsigned < 16) {
sbHex.append("0");
}
sbHex.append(Integer.toString(iUnsigned, 16));
}
sHex = sbHex.toString();
return sHex;
}
/**
* Convert hexadecimal String to byte[].
*
* @param sHex
* @return
* @throws Exception
*/
public static byte[] hexStr2ByteArr(String sHex) throws Exception {
byte[] bytea = new byte[sHex.length() / 2];
String sHexSingle = "";
for (int i = 0; i < bytea.length; i++) {
sHexSingle = sHex.substring(i * 2, i * 2 + 2);
bytea[i] = (byte) Integer.parseInt(sHexSingle, 16);
}
return bytea;
}
}
test case
package pte.stone.test;
import org.junit.Assert;
import org.junit.Test;
import pte.stone.ConverterBetweenHexStringAndByteArray;
public class ConverterBetweenHexStringAndByteArrayTest {
@Test
public void testByteArr2HexStr1() throws Exception{
byte[] bytea1={0,1,126,127};
byte[] bytea2={-128,-127,-2,-1};
String sHex1=ConverterBetweenHexStringAndByteArray.byteArr2HexStr1(bytea1);
String sHex2=ConverterBetweenHexStringAndByteArray.byteArr2HexStr1(bytea2);
String sHex1Exp="00017e7f";
String sHex2Exp="8081feff";
Assert.assertEquals(sHex1Exp, sHex1);
Assert.assertEquals(sHex2Exp, sHex2);
}
@Test
public void testByteArr2HexStr2() throws Exception{
byte[] bytea1={0,1,126,127};
byte[] bytea2={-128,-127,-2,-1};
String sHex1=ConverterBetweenHexStringAndByteArray.byteArr2HexStr2(bytea1);
String sHex2=ConverterBetweenHexStringAndByteArray.byteArr2HexStr2(bytea2);
String sHex1Exp="00017e7f";
String sHex2Exp="8081feff";
Assert.assertEquals(sHex1Exp, sHex1);
Assert.assertEquals(sHex2Exp, sHex2);
}
@Test
public void testHexStr2ByteArr()throws Exception{
String sHex1="00017e7f";
String sHex2="8081feff";
byte[] bytea1=ConverterBetweenHexStringAndByteArray.hexStr2ByteArr(sHex1);
byte[] bytea2=ConverterBetweenHexStringAndByteArray.hexStr2ByteArr(sHex2);
byte[] bytea1Exp={0,1,126,127};
byte[] bytea2Exp={-128,-127,-2,-1};
Assert.assertArrayEquals(bytea1Exp, bytea1);
}
}