SM3.java
public class SM3 {
public static final byte[] iv = { , (byte) , , , ,
, (byte) , (byte) , , , , (byte) ,
(byte) , (byte) , , , (byte) , , ,
(byte) , (byte) , , , (byte) , (byte) ,
(byte) , (byte) , , (byte) , (byte) , ,
};
public static int[] Tj = new int[];
static
{
for (int i = ; i < ; i++)
{
Tj[i] = ;
}
for (int i = ; i < ; i++)
{
Tj[i] = ;
}
}
public static byte[] CF(byte[] V, byte[] B)
{
int[] v, b;
v = convert(V);
b = convert(B);
return convert(CF(v, b));
}
private static int[] convert(byte[] arr)
{
int[] out = new int[arr.length / ];
byte[] tmp = new byte[];
for (int i = ; i < arr.length; i += )
{
System.arraycopy(arr, i, tmp, , );
out[i / ] = bigEndianByteToInt(tmp);
}
return out;
}
private static byte[] convert(int[] arr)
{
byte[] out = new byte[arr.length * ];
byte[] tmp = null;
for (int i = ; i < arr.length; i++)
{
tmp = bigEndianIntToByte(arr[i]);
System.arraycopy(tmp, , out, i * , );
}
return out;
}
public static int[] CF(int[] V, int[] B)
{
int a, b, c, d, e, f, g, h;
int ss1, ss2, tt1, tt2;
a = V[];
b = V[];
c = V[];
d = V[];
e = V[];
f = V[];
g = V[];
h = V[];
/*System.out.println("IV: ");
System.out.print(Integer.toHexString(a)+" ");
System.out.print(Integer.toHexString(b)+" ");
System.out.print(Integer.toHexString(c)+" ");
System.out.print(Integer.toHexString(d)+" ");
System.out.print(Integer.toHexString(e)+" ");
System.out.print(Integer.toHexString(f)+" ");
System.out.print(Integer.toHexString(g)+" ");
System.out.print(Integer.toHexString(h)+" ");
System.out.println("");
System.out.println("");
System.out.println("填充後的消息: ");
for(int i=0; i<B.length; i++)
{
System.out.print(Integer.toHexString(B[i])+" ");
}
System.out.println("");
System.out.println("");*/
int[][] arr = expand(B);
int[] w = arr[];
int[] w1 = arr[];
/*System.out.println("擴充後的消息： ");
System.out.println("W0W1...W67");
print(w);
System.out.println("");
System.out.println("W'0W'1...W'67");
print(w1);
System.out.println("疊代壓縮中間值: ");*/
for (int j = ; j < ; j++)
{
ss1 = (bitCycleLeft(a, ) + e + bitCycleLeft(Tj[j], j));
ss1 = bitCycleLeft(ss1, );
ss2 = ss1 ^ bitCycleLeft(a, );
tt1 = FFj(a, b, c, j) + d + ss2 + w1[j];
tt2 = GGj(e, f, g, j) + h + ss1 + w[j];
d = c;
c = bitCycleLeft(b, );
b = a;
a = tt1;
h = g;
g = bitCycleLeft(f, );
f = e;
e = P0(tt2);
/*System.out.print(j+" ");
System.out.print(Integer.toHexString(a)+" ");
System.out.print(Integer.toHexString(b)+" ");
System.out.print(Integer.toHexString(c)+" ");
System.out.print(Integer.toHexString(d)+" ");
System.out.print(Integer.toHexString(e)+" ");
System.out.print(Integer.toHexString(f)+" ");
System.out.print(Integer.toHexString(g)+" ");
System.out.print(Integer.toHexString(h)+" ");
System.out.println("");*/
}
// System.out.println("");
int[] out = new int[];
out[] = a ^ V[];
out[] = b ^ V[];
out[] = c ^ V[];
out[] = d ^ V[];
out[] = e ^ V[];
out[] = f ^ V[];
out[] = g ^ V[];
out[] = h ^ V[];
return out;
}
private static int[][] expand(int[] B)
{
int W[] = new int[];
int W1[] = new int[];
for (int i = ; i < B.length; i++)
{
W[i] = B[i];
}
for (int i = ; i < ; i++)
{
W[i] = P1(W[i - ] ^ W[i - ] ^ bitCycleLeft(W[i - ], ))
^ bitCycleLeft(W[i - ], ) ^ W[i - ];
}
for (int i = ; i < ; i++)
{
W1[i] = W[i] ^ W[i + ];
}
int arr[][] = new int[][] { W, W1 };
return arr;
}
private static byte[] bigEndianIntToByte(int num)
{
return back(Util.intToBytes(num));
}
private static int bigEndianByteToInt(byte[] bytes)
{
return Util.byteToInt(back(bytes));
}
private static int FFj(int X, int Y, int Z, int j)
{
if (j >= && j <= )
{
return FF1j(X, Y, Z);
}
else
{
return FF2j(X, Y, Z);
}
}
private static int GGj(int X, int Y, int Z, int j)
{
if (j >= && j <= )
{
return GG1j(X, Y, Z);
}
else
{
return GG2j(X, Y, Z);
}
}
// 邏輯位運算函數
private static int FF1j(int X, int Y, int Z)
{
int tmp = X ^ Y ^ Z;
return tmp;
}
private static int FF2j(int X, int Y, int Z)
{
int tmp = ((X & Y) | (X & Z) | (Y & Z));
return tmp;
}
private static int GG1j(int X, int Y, int Z)
{
int tmp = X ^ Y ^ Z;
return tmp;
}
private static int GG2j(int X, int Y, int Z)
{
int tmp = (X & Y) | (~X & Z);
return tmp;
}
private static int P0(int X)
{
int y = rotateLeft(X, );
y = bitCycleLeft(X, );
int z = rotateLeft(X, );
z = bitCycleLeft(X, );
int t = X ^ y ^ z;
return t;
}
private static int P1(int X)
{
int t = X ^ bitCycleLeft(X, ) ^ bitCycleLeft(X, );
return t;
}
/**
* 對最後一個分組位元組資料padding
*
* @param in
* @param bLen
* 分組個數
* @return
*/
public static byte[] padding(byte[] in, int bLen)
{
int k = - ( * in.length + ) % ;
if (k < )
{
k = - ( * in.length + ) % ;
}
k += ;
byte[] padd = new byte[k / ];
padd[] = (byte) ;
long n = in.length * + bLen * ;
byte[] out = new byte[in.length + k / + / ];
int pos = ;
System.arraycopy(in, , out, , in.length);
pos += in.length;
System.arraycopy(padd, , out, pos, padd.length);
pos += padd.length;
byte[] tmp = back(Util.longToBytes(n));
System.arraycopy(tmp, , out, pos, tmp.length);
return out;
}
/**
* 位元組數組逆序
*
* @param in
* @return
*/
private static byte[] back(byte[] in)
{
byte[] out = new byte[in.length];
for (int i = ; i < out.length; i++)
{
out[i] = in[out.length - i - ];
}
return out;
}
public static int rotateLeft(int x, int n)
{
return (x << n) | (x >> ( - n));
}
private static int bitCycleLeft(int n, int bitLen)
{
bitLen %= ;
byte[] tmp = bigEndianIntToByte(n);
int byteLen = bitLen / ;
int len = bitLen % ;
if (byteLen > )
{
tmp = byteCycleLeft(tmp, byteLen);
}
if (len > )
{
tmp = bitSmall8CycleLeft(tmp, len);
}
return bigEndianByteToInt(tmp);
}
private static byte[] bitSmall8CycleLeft(byte[] in, int len)
{
byte[] tmp = new byte[in.length];
int t1, t2, t3;
for (int i = ; i < tmp.length; i++)
{
t1 = (byte) ((in[i] & ) << len);
t2 = (byte) ((in[(i + ) % tmp.length] & ) >> ( - len));
t3 = (byte) (t1 | t2);
tmp[i] = (byte) t3;
}
return tmp;
}
private static byte[] byteCycleLeft(byte[] in, int byteLen)
{
byte[] tmp = new byte[in.length];
System.arraycopy(in, byteLen, tmp, , in.length - byteLen);
System.arraycopy(in, , tmp, in.length - byteLen, byteLen);
return tmp;
}
/*private static void print(int[] arr)
{
for (int i = 0; i < arr.length; i++)
{
System.out.print(Integer.toHexString(arr[i]) + " ");
if ((i + 1) % 16 == 0)
{
System.out.println();
}
}
System.out.println();
}*/
}
SM3Digest.java
import org.bouncycastle.util.encoders.Hex;
public class SM3Digest
{
/** SM3值的長度 */
private static final int BYTE_LENGTH = ;
/** SM3分組長度 */
private static final int BLOCK_LENGTH = ;
/** 緩沖區長度 */
private static final int BUFFER_LENGTH = BLOCK_LENGTH * ;
/** 緩沖區 */
private byte[] xBuf = new byte[BUFFER_LENGTH];
/** 緩沖區偏移量 */
private int xBufOff;
/** 初始向量 */
private byte[] V = SM3.iv.clone();
private int cntBlock = ;
public SM3Digest() {
}
public SM3Digest(SM3Digest t)
{
System.arraycopy(t.xBuf, , this.xBuf, , t.xBuf.length);
this.xBufOff = t.xBufOff;
System.arraycopy(t.V, , this.V, , t.V.length);
}
/**
* SM3結果輸出
*
* @param out 儲存SM3結構的緩沖區
* @param outOff 緩沖區偏移量
* @return
*/
public int doFinal(byte[] out, int outOff)
{
byte[] tmp = doFinal();
System.arraycopy(tmp, , out, , tmp.length);
return BYTE_LENGTH;
}
public void reset()
{
xBufOff = ;
cntBlock = ;
V = SM3.iv.clone();
}
/**
* 明文輸入
*
* @param in
* 明文輸入緩沖區
* @param inOff
* 緩沖區偏移量
* @param len
* 明文長度
*/
public void update(byte[] in, int inOff, int len)
{
int partLen = BUFFER_LENGTH - xBufOff;
int inputLen = len;
int dPos = inOff;
if (partLen < inputLen)
{
System.arraycopy(in, dPos, xBuf, xBufOff, partLen);
inputLen -= partLen;
dPos += partLen;
doUpdate();
while (inputLen > BUFFER_LENGTH)
{
System.arraycopy(in, dPos, xBuf, , BUFFER_LENGTH);
inputLen -= BUFFER_LENGTH;
dPos += BUFFER_LENGTH;
doUpdate();
}
}
System.arraycopy(in, dPos, xBuf, xBufOff, inputLen);
xBufOff += inputLen;
}
private void doUpdate()
{
byte[] B = new byte[BLOCK_LENGTH];
for (int i = ; i < BUFFER_LENGTH; i += BLOCK_LENGTH)
{
System.arraycopy(xBuf, i, B, , B.length);
doHash(B);
}
xBufOff = ;
}
private void doHash(byte[] B)
{
byte[] tmp = SM3.CF(V, B);
System.arraycopy(tmp, , V, , V.length);
cntBlock++;
}
private byte[] doFinal()
{
byte[] B = new byte[BLOCK_LENGTH];
byte[] buffer = new byte[xBufOff];
System.arraycopy(xBuf, , buffer, , buffer.length);
byte[] tmp = SM3.padding(buffer, cntBlock);
for (int i = ; i < tmp.length; i += BLOCK_LENGTH)
{
System.arraycopy(tmp, i, B, , B.length);
doHash(B);
}
return V;
}
public void update(byte in)
{
byte[] buffer = new byte[] { in };
update(buffer, , );
}
public int getDigestSize()
{
return BYTE_LENGTH;
}
public static void main(String[] args) {
byte[] md = new byte[];
byte[] md2 = new byte[];
byte[] msg1 = "abc".getBytes();
byte[] msg2 = "abcdabcdabcdabcdabcdabcdabcdabcdabcdabcdabcdabcdabcdabcdabcdabcd".getBytes();
SM3Digest sm3 = new SM3Digest();
// sm3.update(msg1, 0, msg1.length);
// sm3.doFinal(md, 0);
// String s = new String(Hex.encode(md));
// System.out.println("msg1:" + s);
sm3.update(msg2, , msg2.length);
sm3.doFinal(md2, );
String s2 = new String(Hex.encode(md2));
System.out.println("msg2:" + s2);
}
}
Util.java
import java.math.BigInteger;
public class Util
{
/**
* 整形轉換成網絡傳輸的位元組流（位元組數組）型資料
*
* @param num 一個整型資料
* @return 4個位元組的自己數組
*/
public static byte[] intToBytes(int num)
{
byte[] bytes = new byte[];
bytes[] = (byte) ( & (num >> ));
bytes[] = (byte) ( & (num >> ));
bytes[] = (byte) ( & (num >> ));
bytes[] = (byte) ( & (num >> ));
return bytes;
}
/**
* 四個位元組的位元組資料轉換成一個整形資料
*
* @param bytes 4個位元組的位元組數組
* @return 一個整型資料
*/
public static int byteToInt(byte[] bytes)
{
int num = ;
int temp;
temp = ( & (bytes[])) << ;
num = num | temp;
temp = ( & (bytes[])) << ;
num = num | temp;
temp = ( & (bytes[])) << ;
num = num | temp;
temp = ( & (bytes[])) << ;
num = num | temp;
return num;
}
/**
* 長整形轉換成網絡傳輸的位元組流（位元組數組）型資料
*
* @param num 一個長整型資料
* @return 4個位元組的自己數組
*/
public static byte[] longToBytes(long num)
{
byte[] bytes = new byte[];
for (int i = ; i < ; i++)
{
bytes[i] = (byte) ( & (num >> (i * )));
}
return bytes;
}
/**
* 大數字轉換位元組流（位元組數組）型資料
*
* @param n
* @return
*/
public static byte[] byteConvert32Bytes(BigInteger n)
{
byte tmpd[] = (byte[])null;
if(n == null)
{
return null;
}
if(n.toByteArray().length == )
{
tmpd = new byte[];
System.arraycopy(n.toByteArray(), , tmpd, , );
}
else if(n.toByteArray().length == )
{
tmpd = n.toByteArray();
}
else
{
tmpd = new byte[];
for(int i = ; i < - n.toByteArray().length; i++)
{
tmpd[i] = ;
}
System.arraycopy(n.toByteArray(), , tmpd, - n.toByteArray().length, n.toByteArray().length);
}
return tmpd;
}
/**
* 換位元組流（位元組數組）型資料轉大數字
*
* @param b
* @return
*/
public static BigInteger byteConvertInteger(byte[] b)
{
if (b[] < )
{
byte[] temp = new byte[b.length + ];
temp[] = ;
System.arraycopy(b, , temp, , b.length);
return new BigInteger(temp);
}
return new BigInteger(b);
}
/**
* 根據位元組數組獲得值(十六進制數字)
*
* @param bytes
* @return
*/
public static String getHexString(byte[] bytes)
{
return getHexString(bytes, true);
}
/**
* 根據位元組數組獲得值(十六進制數字)
*
* @param bytes
* @param upperCase
* @return
*/
public static String getHexString(byte[] bytes, boolean upperCase)
{
String ret = "";
for (int i = ; i < bytes.length; i++)
{
ret += Integer.toString((bytes[i] & ) + , ).substring();
}
return upperCase ? ret.toUpperCase() : ret;
}
/**
* 列印十六進制字元串
*
* @param bytes
*/
public static void printHexString(byte[] bytes)
{
for (int i = ; i < bytes.length; i++)
{
String hex = Integer.toHexString(bytes[i] & );
if (hex.length() == )
{
hex = '0' + hex;
}
System.out.print("0x" + hex.toUpperCase() + ",");
}
System.out.println("");
}
/**
* Convert hex string to byte[]
*
* @param hexString
* the hex string
* @return byte[]
*/
public static byte[] hexStringToBytes(String hexString)
{
if (hexString == null || hexString.equals(""))
{
return null;
}
hexString = hexString.toUpperCase();
int length = hexString.length() / ;
char[] hexChars = hexString.toCharArray();
byte[] d = new byte[length];
for (int i = ; i < length; i++)
{
int pos = i * ;
d[i] = (byte) (charToByte(hexChars[pos]) << | charToByte(hexChars[pos + ]));
}
return d;
}
/**
* Convert char to byte
*
* @param c
* char
* @return byte
*/
public static byte charToByte(char c)
{
return (byte) "0123456789ABCDEF".indexOf(c);
}
/**
* 用于建立十六進制字元的輸出的小寫字元數組
*/
private static final char[] DIGITS_LOWER = {'0', '1', '2', '3', '4', '5',
'6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
/**
* 用于建立十六進制字元的輸出的大寫字元數組
*/
private static final char[] DIGITS_UPPER = {'0', '1', '2', '3', '4', '5',
'6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};
/**
* 将位元組數組轉換為十六進制字元數組
*
* @param data byte[]
* @return 十六進制char[]
*/
public static char[] encodeHex(byte[] data) {
return encodeHex(data, true);
}
/**
* 将位元組數組轉換為十六進制字元數組
*
* @param data byte[]
* @param toLowerCase <code>true</code> 傳換成小寫格式 ， <code>false</code> 傳換成大寫格式
* @return 十六進制char[]
*/
public static char[] encodeHex(byte[] data, boolean toLowerCase) {
return encodeHex(data, toLowerCase ? DIGITS_LOWER : DIGITS_UPPER);
}
/**
* 将位元組數組轉換為十六進制字元數組
*
* @param data byte[]
* @param toDigits 用于控制輸出的char[]
* @return 十六進制char[]
*/
protected static char[] encodeHex(byte[] data, char[] toDigits) {
int l = data.length;
char[] out = new char[l << ];
// two characters form the hex value.
for (int i = , j = ; i < l; i++) {
out[j++] = toDigits[( & data[i]) >>> ];
out[j++] = toDigits[ & data[i]];
}
return out;
}
/**
* 将位元組數組轉換為十六進制字元串
*
* @param data byte[]
* @return 十六進制String
*/
public static String encodeHexString(byte[] data) {
return encodeHexString(data, true);
}
/**
* 将位元組數組轉換為十六進制字元串
*
* @param data byte[]
* @param toLowerCase <code>true</code> 傳換成小寫格式 ， <code>false</code> 傳換成大寫格式
* @return 十六進制String
*/
public static String encodeHexString(byte[] data, boolean toLowerCase) {
return encodeHexString(data, toLowerCase ? DIGITS_LOWER : DIGITS_UPPER);
}
/**
* 将位元組數組轉換為十六進制字元串
*
* @param data byte[]
* @param toDigits 用于控制輸出的char[]
* @return 十六進制String
*/
protected static String encodeHexString(byte[] data, char[] toDigits) {
return new String(encodeHex(data, toDigits));
}
/**
* 将十六進制字元數組轉換為位元組數組
*
* @param data 十六進制char[]
* @return byte[]
* @throws RuntimeException 如果源十六進制字元數組是一個奇怪的長度，将抛出運作時異常
*/
public static byte[] decodeHex(char[] data) {
int len = data.length;
if ((len & ) != ) {
throw new RuntimeException("Odd number of characters.");
}
byte[] out = new byte[len >> ];
// two characters form the hex value.
for (int i = , j = ; j < len; i++) {
int f = toDigit(data[j], j) << ;
j++;
f = f | toDigit(data[j], j);
j++;
out[i] = (byte) (f & );
}
return out;
}
/**
* 将十六進制字元轉換成一個整數
*
* @param ch 十六進制char
* @param index 十六進制字元在字元數組中的位置
* @return 一個整數
* @throws RuntimeException 當ch不是一個合法的十六進制字元時，抛出運作時異常
*/
protected static int toDigit(char ch, int index) {
int digit = Character.digit(ch, );
if (digit == -) {
throw new RuntimeException("Illegal hexadecimal character " + ch
+ " at index " + index);
}
return digit;
}
/**
* 數字字元串轉ASCII碼字元串
*
* @param content
* 字元串
* @return ASCII字元串
*/
public static String StringToAsciiString(String content) {
String result = "";
int max = content.length();
for (int i = ; i < max; i++) {
char c = content.charAt(i);
String b = Integer.toHexString(c);
result = result + b;
}
return result;
}
/**
* 十六進制轉字元串
*
* @param hexString
* 十六進制字元串
* @param encodeType
* 編碼類型4：Unicode，2：普通編碼
* @return 字元串
*/
public static String hexStringToString(String hexString, int encodeType) {
String result = "";
int max = hexString.length() / encodeType;
for (int i = ; i < max; i++) {
char c = (char) hexStringToAlgorism(hexString
.substring(i * encodeType, (i + ) * encodeType));
result += c;
}
return result;
}
/**
* 十六進制字元串裝十進制
*
* @param hex
* 十六進制字元串
* @return 十進制數值
*/
public static int hexStringToAlgorism(String hex) {
hex = hex.toUpperCase();
int max = hex.length();
int result = ;
for (int i = max; i > ; i--) {
char c = hex.charAt(i - );
int algorism = ;
if (c >= '0' && c <= '9') {
algorism = c - '0';
} else {
algorism = c - ;
}
result += Math.pow(, max - i) * algorism;
}
return result;
}
/**
* 十六轉二進制
*
* @param hex
* 十六進制字元串
* @return 二進制字元串
*/
public static String hexStringToBinary(String hex) {
hex = hex.toUpperCase();
String result = "";
int max = hex.length();
for (int i = ; i < max; i++) {
char c = hex.charAt(i);
switch (c) {
case '0':
result += "0000";
break;
case '1':
result += "0001";
break;
case '2':
result += "0010";
break;
case '3':
result += "0011";
break;
case '4':
result += "0100";
break;
case '5':
result += "0101";
break;
case '6':
result += "0110";
break;
case '7':
result += "0111";
break;
case '8':
result += "1000";
break;
case '9':
result += "1001";
break;
case 'A':
result += "1010";
break;
case 'B':
result += "1011";
break;
case 'C':
result += "1100";
break;
case 'D':
result += "1101";
break;
case 'E':
result += "1110";
break;
case 'F':
result += "1111";
break;
}
}
return result;
}
/**
* ASCII碼字元串轉數字字元串
*
* @param content
* ASCII字元串
* @return 字元串
*/
public static String AsciiStringToString(String content) {
String result = "";
int length = content.length() / ;
for (int i = ; i < length; i++) {
String c = content.substring(i * , i * + );
int a = hexStringToAlgorism(c);
char b = (char) a;
String d = String.valueOf(b);
result += d;
}
return result;
}
/**
* 将十進制轉換為指定長度的十六進制字元串
*
* @param algorism
* int 十進制數字
* @param maxLength
* int 轉換後的十六進制字元串長度
* @return String 轉換後的十六進制字元串
*/
public static String algorismToHexString(int algorism, int maxLength) {
String result = "";
result = Integer.toHexString(algorism);
if (result.length() % == ) {
result = "0" + result;
}
return patchHexString(result.toUpperCase(), maxLength);
}
/**
* 位元組數組轉為普通字元串（ASCII對應的字元）
*
* @param bytearray
* byte[]
* @return String
*/
public static String byteToString(byte[] bytearray) {
String result = "";
char temp;
int length = bytearray.length;
for (int i = ; i < length; i++) {
temp = (char) bytearray[i];
result += temp;
}
return result;
}
/**
* 二進制字元串轉十進制
*
* @param binary
* 二進制字元串
* @return 十進制數值
*/
public static int binaryToAlgorism(String binary) {
int max = binary.length();
int result = ;
for (int i = max; i > ; i--) {
char c = binary.charAt(i - );
int algorism = c - '0';
result += Math.pow(, max - i) * algorism;
}
return result;
}
/**
* 十進制轉換為十六進制字元串
*
* @param algorism
* int 十進制的數字
* @return String 對應的十六進制字元串
*/
public static String algorismToHEXString(int algorism) {
String result = "";
result = Integer.toHexString(algorism);
if (result.length() % == ) {
result = "0" + result;
}
result = result.toUpperCase();
return result;
}
/**
* HEX字元串前補0，主要用于長度位數不足。
*
* @param str
* String 需要補充長度的十六進制字元串
* @param maxLength
* int 補充後十六進制字元串的長度
* @return 補充結果
*/
static public String patchHexString(String str, int maxLength) {
String temp = "";
for (int i = ; i < maxLength - str.length(); i++) {
temp = "0" + temp;
}
str = (temp + str).substring(, maxLength);
return str;
}
/**
* 将一個字元串轉換為int
*
* @param s
* String 要轉換的字元串
* @param defaultInt
* int 如果出現異常,預設傳回的數字
* @param radix
* int 要轉換的字元串是什麼進制的,如16 8 10.
* @return int 轉換後的數字
*/
public static int parseToInt(String s, int defaultInt, int radix) {
int i = ;
try {
i = Integer.parseInt(s, radix);
} catch (NumberFormatException ex) {
i = defaultInt;
}
return i;
}
/**
* 将一個十進制形式的數字字元串轉換為int
*
* @param s
* String 要轉換的字元串
* @param defaultInt
* int 如果出現異常,預設傳回的數字
* @return int 轉換後的數字
*/
public static int parseToInt(String s, int defaultInt) {
int i = ;
try {
i = Integer.parseInt(s);
} catch (NumberFormatException ex) {
i = defaultInt;
}
return i;
}
/**
* 十六進制串轉化為byte數組
*
* @return the array of byte
*/
public static byte[] hexToByte(String hex)
throws IllegalArgumentException {
if (hex.length() % != ) {
throw new IllegalArgumentException();
}
char[] arr = hex.toCharArray();
byte[] b = new byte[hex.length() / ];
for (int i = , j = , l = hex.length(); i < l; i++, j++) {
String swap = "" + arr[i++] + arr[i];
int byteint = Integer.parseInt(swap, ) & ;
b[j] = new Integer(byteint).byteValue();
}
return b;
}
/**
* 位元組數組轉換為十六進制字元串
*
* @param b
* byte[] 需要轉換的位元組數組
* @return String 十六進制字元串
*/
public static String byteToHex(byte b[]) {
if (b == null) {
throw new IllegalArgumentException(
"Argument b ( byte array ) is null! ");
}
String hs = "";
String stmp = "";
for (int n = ; n < b.length; n++) {
stmp = Integer.toHexString(b[n] & );
if (stmp.length() == ) {
hs = hs + "0" + stmp;
} else {
hs = hs + stmp;
}
}
return hs.toUpperCase();
}
public static byte[] subByte(byte[] input, int startIndex, int length) {
byte[] bt = new byte[length];
for (int i = ; i < length; i++) {
bt[i] = input[i + startIndex];
}
return bt;
}
}
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