java中long,int,short与byte数组之间的转换

//long类型转成byte数组 
  public static byte[] longToByte(long number) { 
        long temp = number; 
        byte[] b = new byte[8]; 
        for (int i = 0; i < b.length; i++) { 
            b[i] = new Long(temp & 0xff).byteValue();// 
将最低位保存在最低位 
            temp = temp >> 8; // 向右移8位 
        } 
        return b; 
    } 
    
    //byte数组转成long 
    public static long byteToLong(byte[] b) { 
        long s = 0; 
        long s0 = b[0] & 0xff;// 最低位 
        long s1 = b[1] & 0xff; 
        long s2 = b[2] & 0xff; 
        long s3 = b[3] & 0xff; 
        long s4 = b[4] & 0xff;// 最低位 
        long s5 = b[5] & 0xff; 
        long s6 = b[6] & 0xff; 
        long s7 = b[7] & 0xff; 
 
        // s0不变 
        s1 <<= 8; 
        s2 <<= 16; 
        s3 <<= 24; 
        s4 <<= 8 * 4; 
        s5 <<= 8 * 5; 
        s6 <<= 8 * 6; 
        s7 <<= 8 * 7; 
        s = s0 | s1 | s2 | s3 | s4 | s5 | s6 | s7; 
        return s; 
    } 
 
/** 
     * 注释：int到字节数组的转换！ 
     * 
     * @param number 
     * @return 
     */ 
    public static byte[] intToByte(int number) { 
        int temp = number; 
        byte[] b = new byte[4]; 
        for (int i = 0; i < b.length; i++) { 
            b[i] = new Integer(temp & 0xff).byteValue();// 
将最低位保存在最低位 
            temp = temp >> 8; // 向右移8位 
        } 
        return b; 
    } 
 
    /** 
     * 注释：字节数组到int的转换！ 
     * 
     * @param b 
     * @return 
     */ 
    public static int byteToInt(byte[] b) { 
        int s = 0; 
        int s0 = b[0] & 0xff;// 最低位 
        int s1 = b[1] & 0xff; 
        int s2 = b[2] & 0xff; 
        int s3 = b[3] & 0xff; 
        s3 <<= 24; 
        s2 <<= 16; 
        s1 <<= 8; 
        s = s0 | s1 | s2 | s3; 
        return s; 
    } 
 
    /** 
     * 注释：short到字节数组的转换！ 
     * 
     * @param s 
     * @return 
     */ 
    public static byte[] shortToByte(short number) { 
        int temp = number; 
        byte[] b = new byte[2]; 
        for (int i = 0; i < b.length; i++) { 
            b[i] = new Integer(temp & 0xff).byteValue();// 
将最低位保存在最低位 
            temp = temp >> 8; // 向右移8位 
        } 
        return b; 
    } 
 
    /** 
     * 注释：字节数组到short的转换！ 
     * 
     * @param b 
     * @return 
     */ 
    public static short byteToShort(byte[] b) { 
        short s = 0; 
        short s0 = (short) (b[0] & 0xff);// 最低位 
        short s1 = (short) (b[1] & 0xff); 
        s1 <<= 8; 
        s = (short) (s0 | s1); 
        return s; 
    }

public static byte[] shortToBytes(short n) {
byte[] b = new byte[2];
b[1] = (byte) (n & 0xff);
b[0] = (byte) ((n >> 8) & 0xff);
return b;
}
public static short bytesToShort(byte[] b) {
return (short) (b[1] & 0xff
| (b[0] & 0xff) << 8);
}
/**
* int类型转换成byte[]
*
* @param num
* int数
* @return byte[]
*/
public static byte[] intToBytes(int num) {
byte[] b = new byte[4];
for (int i = 0; i < 4; i++) {
b[i] = (byte) (num >>> (24 - i * 8));
}
return b;
}
public static int bytes2int(byte[] b) {
//byte[] b=new byte[]{1,2,3,4};
int mask = 0xff;
int temp = 0;
int res = 0;
for (int i = 0; i < 4; i++) {
res <<= 8;
temp = b[i] & mask;
res |= temp;
}
return res;
}
public static byte[] longToBytes(long num) {
byte[] b = new byte[8];
for (int i = 0; i < 8; i++) {
b[i] = (byte) (num >>> (56 - i * 8));
}
return b;
}
public static String str2HexStr(String str) {
char[] chars = "0123456789ABCDEF".toCharArray();
StringBuilder sb = new StringBuilder("");
byte[] bs = str.getBytes();
int bit;
for (int i = 0; i < bs.length; i++) {
bit = (bs[i] & 0x0f0) >> 4;
sb.append(chars[bit]);
bit = bs[i] & 0x0f;
sb.append(chars[bit]);
}
return sb.toString();
}
public static String bytesToHexString(byte[] bArray) {
StringBuffer sb = new StringBuffer(bArray.length);
String sTemp;
for (int i = 0; i < bArray.length; i++) {
sTemp = Integer.toHexString(0xFF & bArray[i]);
if (sTemp.length() < 2) {
sb.append(0);
}
sb.append(sTemp.toUpperCase());
}
return sb.toString();
}
public static byte[] hexStringToBytes(String hexString) {
String chars = "0123456789ABCDEF";
if (hexString == null || hexString.equals("")) {
return null;
}
hexString = hexString.toUpperCase();
int length = hexString.length() / 2;
char[] hexChars = hexString.toCharArray();
byte[] d = new byte[length];
for (int i = 0; i < length; i++) {
int pos = i * 2;
d[i] = (byte) (chars.indexOf(hexChars[pos]) << 4 | chars.indexOf(hexChars[pos + 1]));
}
return d;
}

public static byte[] shortToBytes(short n) {
byte[] b = new byte[2];
b[1] = (byte) (n & 0xff);
b[0] = (byte) ((n >> 8) & 0xff);
return b;
}
public static short bytesToShort(byte[] b) {
return (short) (b[1] & 0xff
| (b[0] & 0xff) << 8);
}
/**
* int类型转换成byte[]
*
* @param num
* int数
* @return byte[]
*/
public static byte[] intToBytes(int num) {
byte[] b = new byte[4];
for (int i = 0; i < 4; i++) {
b[i] = (byte) (num >>> (24 - i * 8));
}
return b;
}
public static int bytes2int(byte[] b) {
//byte[] b=new byte[]{1,2,3,4};
int mask = 0xff;
int temp = 0;
int res = 0;
for (int i = 0; i < 4; i++) {
res <<= 8;
temp = b[i] & mask;
res |= temp;
}
return res;
}
public static byte[] longToBytes(long num) {
byte[] b = new byte[8];
for (int i = 0; i < 8; i++) {
b[i] = (byte) (num >>> (56 - i * 8));
}
return b;
}
public static String str2HexStr(String str) {
char[] chars = "0123456789ABCDEF".toCharArray();
StringBuilder sb = new StringBuilder("");
byte[] bs = str.getBytes();
int bit;
for (int i = 0; i < bs.length; i++) {
bit = (bs[i] & 0x0f0) >> 4;
sb.append(chars[bit]);
bit = bs[i] & 0x0f;
sb.append(chars[bit]);
}
return sb.toString();
}
public static String bytesToHexString(byte[] bArray) {
StringBuffer sb = new StringBuffer(bArray.length);
String sTemp;
for (int i = 0; i < bArray.length; i++) {
sTemp = Integer.toHexString(0xFF & bArray[i]);
if (sTemp.length() < 2) {
sb.append(0);
}
sb.append(sTemp.toUpperCase());
}
return sb.toString();
}
public static byte[] hexStringToBytes(String hexString) {
String chars = "0123456789ABCDEF";
if (hexString == null || hexString.equals("")) {
return null;
}
hexString = hexString.toUpperCase();
int length = hexString.length() / 2;
char[] hexChars = hexString.toCharArray();
byte[] d = new byte[length];
for (int i = 0; i < length; i++) {
int pos = i * 2;
d[i] = (byte) (chars.indexOf(hexChars[pos]) << 4 | chars.indexOf(hexChars[pos + 1]));
}
return d;
}