在我们进行Socket自定义协议网络字节传输的时候，我们不能直接使用从网络传输过来的字节数组进行解析，我们首先需要做一次转换。
直接上代码，一个ByteConvert，byte[] , 基本数据类型，String之间的转换：
import java.nio.ByteBuffer;
public class ByteConvert {
public static byte intToByte(int x) {
return (byte) x;
}
public static int byteToInt(byte b) {
// Java 总是把 byte 当做有符处理；我们可以通过将其和 0xFF 进行二进制与得到它的无符值
return b & 0xFF;
}
private static ByteBuffer buffer = ByteBuffer.allocate(8);
// byte 数组与 long 的相互转换
public static byte[] longToBytes2(long x) {
buffer.putLong(0, x);
return buffer.array();
}
public static long bytesToLong2(byte[] bytes) {
buffer.put(bytes, 0, bytes.length);
buffer.flip();
return buffer.getLong();
}
public static char tochar(byte[] x) {
return (char) ((x[0] << 8) | (x[1] & 0xff));
}
// =================================================================================
public static byte[] longToBytes(long n) {
byte[] b = new byte[8];
b[7] = (byte) (n & 0xff);
b[6] = (byte) (n >> 8 & 0xff);
b[5] = (byte) (n >> 16 & 0xff);
b[4] = (byte) (n >> 24 & 0xff);
b[3] = (byte) (n >> 32 & 0xff);
b[2] = (byte) (n >> 40 & 0xff);
b[1] = (byte) (n >> 48 & 0xff);
b[0] = (byte) (n >> 56 & 0xff);
return b;
}
public static void longToBytes(long n, byte[] array, int offset) {
array[7 + offset] = (byte) (n & 0xff);
array[6 + offset] = (byte) (n >> 8 & 0xff);
array[5 + offset] = (byte) (n >> 16 & 0xff);
array[4 + offset] = (byte) (n >> 24 & 0xff);
array[3 + offset] = (byte) (n >> 32 & 0xff);
array[2 + offset] = (byte) (n >> 40 & 0xff);
array[1 + offset] = (byte) (n >> 48 & 0xff);
array[0 + offset] = (byte) (n >> 56 & 0xff);
}
public static long bytesToLong(byte[] array) {
return ((((long) array[0] & 0xff) << 56)
| (((long) array[1] & 0xff) << 48)
| (((long) array[2] & 0xff) << 40)
| (((long) array[3] & 0xff) << 32)
| (((long) array[4] & 0xff) << 24)
| (((long) array[5] & 0xff) << 16)
| (((long) array[6] & 0xff) << 8) | (((long) array[7] & 0xff) << 0));
}
public static long bytesToLong(byte[] array, int offset) {
return ((((long) array[offset + 0] & 0xff) << 56)
| (((long) array[offset + 1] & 0xff) << 48)
| (((long) array[offset + 2] & 0xff) << 40)
| (((long) array[offset + 3] & 0xff) << 32)
| (((long) array[offset + 4] & 0xff) << 24)
| (((long) array[offset + 5] & 0xff) << 16)
| (((long) array[offset + 6] & 0xff) << 8) | (((long) array[offset + 7] & 0xff) << 0));
}
public static byte[] intToBytes(int n) {
byte[] b = new byte[4];
b[3] = (byte) (n & 0xff);
b[2] = (byte) (n >> 8 & 0xff);
b[1] = (byte) (n >> 16 & 0xff);
b[0] = (byte) (n >> 24 & 0xff);
return b;
}
public static void intToBytes(int n, byte[] array, int offset) {
array[3 + offset] = (byte) (n & 0xff);
array[2 + offset] = (byte) (n >> 8 & 0xff);
array[1 + offset] = (byte) (n >> 16 & 0xff);
array[offset] = (byte) (n >> 24 & 0xff);
}
public static int bytesToInt(byte b[]) {
return b[3] & 0xff | (b[2] & 0xff) << 8 | (b[1] & 0xff) << 16
| (b[0] & 0xff) << 24;
}
public static int bytesToInt(byte b[], int offset) {
return b[offset + 3] & 0xff | (b[offset + 2] & 0xff) << 8
| (b[offset + 1] & 0xff) << 16 | (b[offset] & 0xff) << 24;
}
public static byte[] uintToBytes(long n) {
byte[] b = new byte[4];
b[3] = (byte) (n & 0xff);
b[2] = (byte) (n >> 8 & 0xff);
b[1] = (byte) (n >> 16 & 0xff);
b[0] = (byte) (n >> 24 & 0xff);
return b;
}
public static void uintToBytes(long n, byte[] array, int offset) {
array[3 + offset] = (byte) (n);
array[2 + offset] = (byte) (n >> 8 & 0xff);
array[1 + offset] = (byte) (n >> 16 & 0xff);
array[offset] = (byte) (n >> 24 & 0xff);
}
public static long bytesToUint(byte[] array) {
return ((long) (array[3] & 0xff)) | ((long) (array[2] & 0xff)) << 8
| ((long) (array[1] & 0xff)) << 16
| ((long) (array[0] & 0xff)) << 24;
}
public static long bytesToUint(byte[] array, int offset) {
return ((long) (array[offset + 3] & 0xff))
| ((long) (array[offset + 2] & 0xff)) << 8
| ((long) (array[offset + 1] & 0xff)) << 16
| ((long) (array[offset] & 0xff)) << 24;
}
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 void shortToBytes(short n, byte[] array, int offset) {
array[offset + 1] = (byte) (n & 0xff);
array[offset] = (byte) ((n >> 8) & 0xff);
}
public static short bytesToShort(byte[] b) {
return (short) (b[1] & 0xff | (b[0] & 0xff) << 8);
}
public static short bytesToShort(byte[] b, int offset) {
return (short) (b[offset + 1] & 0xff | (b[offset] & 0xff) << 8);
}
public static byte[] ushortToBytes(int n) {
byte[] b = new byte[2];
b[1] = (byte) (n & 0xff);
b[0] = (byte) ((n >> 8) & 0xff);
return b;
}
public static void ushortToBytes(int n, byte[] array, int offset) {
array[offset + 1] = (byte) (n & 0xff);
array[offset] = (byte) ((n >> 8) & 0xff);
}
public static int bytesToUshort(byte b[]) {
return b[1] & 0xff | (b[0] & 0xff) << 8;
}
public static int bytesToUshort(byte b[], int offset) {
return b[offset + 1] & 0xff | (b[offset] & 0xff) << 8;
}
public static byte[] ubyteToBytes(int n) {
byte[] b = new byte[1];
b[0] = (byte) (n & 0xff);
return b;
}
public static void ubyteToBytes(int n, byte[] array, int offset) {
array[0] = (byte) (n & 0xff);
}
public static int bytesToUbyte(byte[] array) {
return array[0] & 0xff;
}
public static int bytesToUbyte(byte[] array, int offset) {
return array[offset] & 0xff;
}
public static String bytesToString(byte[] array){
return new String(array);
}
public static String bytesToString(byte[] array,int beginIndex,int len){
byte[] b = new byte[len];
for (int i = 0; i < len; i++) {
b[i] = array[beginIndex+i];
}
return new String(b);
}
public static byte[] bytesToBytes(byte[] array,int beginIndex,int len){
byte[] b = new byte[len];
for (int i = 0; i < len; i++) {
b[i] = array[beginIndex+i];
}
return b;
}
}
