JAVA中byte数组跟基本数据类型转换工具类
例如：解析UDP数据报文
package org.jeecg.modules.largescreen.udp.util;
/**
* 字节数组与基本数据类型的转换
* byte、short、int、float、long、double、16进制字符串
*/
public class ByteArrayUtil {
/**
* 字节数组转 short，小端
*/
public static short byteArray2Short_Little_Endian(byte[] array) {
// 数组长度有误
if (array.length > 2) {
return 0;
}
short value = 0;
for (int i = 0; i < array.length; i++) {
// & 0xff，除去符号位干扰
value |= ((array[i] & 0xff) << (i * 8));
}
return value;
}
/**
* 字节数组转 short，大端
*/
public static short byteArray2Short_Big_Endian(byte[] array) {
// 数组长度有误
if (array.length > 2) {
return 0;
}
short value = 0;
for (int i = 0; i < array.length ; i++) {
value |= ((array[i] & 0xff) << ((array.length - i - 1) * 8));
}
return value;
}
/**
* 字节数组转 int，小端
*/
public static int byteArray2Int_Little_Endian(byte[] array) {
// 数组长度有误
if (array.length > 4) {
return 0;
}
int value = 0;
for (int i = 0; i < array.length; i++) {
value |= ((array[i] & 0xff) << (i * 8));
}
return value;
}
/**
* 字节数组转 int，大端
*/
public static int byteArray2Int_Big_Endian(byte[] array) {
// 数组长度有误
if (array.length > 4) {
return 0;
}
int value = 0;
for (int i = 0; i < array.length ; i++) {
value |= ((array[i] & 0xff) << ((array.length - i - 1) * 8));
}
return value;
}
/**
* 字节数组转 float，小端
*/
public static float byteArray2Float_Little_Endian(byte[] array) {
// 数组长度有误
if (array.length != 4) {
return 0;
}
return Float.intBitsToFloat(byteArray2Int_Little_Endian(array));
}
/**
* 字节数组转 float，大端
*/
public static float byteArray2Float_Big_Endian(byte[] array) {
// 数组长度有误
if (array.length > 4) {
return 0;
}
return Float.intBitsToFloat(byteArray2Int_Big_Endian(array));
}
/**
* 字节数组转 long，小端
*/
public static long byteArray2Long_Little_Endian(byte[] array) {
// 数组长度有误
if (array.length != 8) {
return 0;
}
long value = 0;
for (int i = 0; i < array.length ; i++) {
// 需要转long再位移，否则int丢失精度
value |= ((long)(array[i]& 0xff) << (i * 8));
}
return value;
}
/**
* 字节数组转 long，大端
*/
public static long byteArray2Long_Big_Endian(byte[] array) {
// 数组长度有误
if (array.length != 8) {
return 0;
}
long value = 0;
for (int i = 0; i < array.length ; i++) {
value |= ((long)(array[i] & 0xff) << ((array.length - i - 1) * 8));
}
return value;
}
/**
* 字节数组转 double，小端
*/
public static double byteArray2Double_Little_Endian(byte[] array) {
// 数组长度有误
if (array.length != 8) {
return 0;
}
return Double.longBitsToDouble(byteArray2Long_Little_Endian(array));
}
/**
* 字节数组转 double，大端
*/
public static double byteArray2Double_Big_Endian(byte[] array) {
// 数组长度有误
if (array.length != 8) {
return 0;
}
return Double.longBitsToDouble(byteArray2Long_Big_Endian(array));
}
/**
* 字节数组转 HexString
*/
public static String byteArray2HexString(byte[] array) {
StringBuilder builder = new StringBuilder();
for (byte b : array) {
String s = Integer.toHexString(b & 0xff);
if (s.length() < 2) {
builder.append("0");
}
builder.append(s);
}
return builder.toString().toUpperCase();
}
//---------------------------------华丽的分割线-------------------------------------
/**
* short 转字节数组，小端
*/
public static byte[] short2ByteArray_Little_Endian(short s) {
byte[] array = new byte[2];
for (int i = 0; i < array.length; i++) {
array[i] = (byte) (s >> (i * 8));
}
return array;
}
/**
* short 转字节数组，大端
*/
public static byte[] short2ByteArray_Big_Endian(short s) {
byte[] array = new byte[2];
for (int i = 0; i < array.length; i++) {
array[array.length - 1 - i] = (byte) (s >> (i * 8));
}
return array;
}
/**
* int 转字节数组，小端
*/
public static byte[] int2ByteArray_Little_Endian(int s) {
byte[] array = new byte[4];
for (int i = 0; i < array.length; i++) {
array[i] = (byte) (s >> (i * 8));
}
return array;
}
/**
* int 转字节数组，大端
*/
public static byte[] int2ByteArray_Big_Endian(int s) {
byte[] array = new byte[4];
for (int i = 0; i < array.length; i++) {
array[array.length - 1 - i] = (byte) (s >> (i * 8));
}
return array;
}
/**
* float 转字节数组，小端
*/
public static byte[] float2ByteArray_Little_Endian(float f) {
return int2ByteArray_Little_Endian(Float.floatToIntBits(f));
}
/**
* float 转字节数组，大端
*/
public static byte[] float2ByteArray_Big_Endian(float f) {
return int2ByteArray_Big_Endian(Float.floatToIntBits(f));
}
/**
* long 转字节数组，小端
*/
public static byte[] long2ByteArray_Little_Endian(long l) {
byte[] array = new byte[8];
for (int i = 0; i < array.length; i++) {
array[i] = (byte) (l >> (i * 8));
}
return array;
}
/**
* long 转字节数组，大端
*/
public static byte[] long2ByteArray_Big_Endian(long l) {
byte[] array = new byte[8];
for (int i = 0; i < array.length; i++) {
array[array.length - 1 - i] = (byte) (l >> (i * 8));
}
return array;
}
/**
* double 转字节数组，小端
*/
public static byte[] double2ByteArray_Little_Endian(double d) {
return long2ByteArray_Little_Endian(Double.doubleToLongBits(d));
}
/**
* double 转字节数组，大端
*/
public static byte[] double2ByteArray_Big_Endian(double d) {
return long2ByteArray_Big_Endian(Double.doubleToLongBits(d));
}
/**
* HexString 转字节数组
*/
public static byte[] hexString2ByteArray(String hexString) {
// 两个十六进制字符一个 byte，单数则有误
if (hexString.length() % 2 != 0) {
return null;
}
byte[] array = new byte[hexString.length() / 2];
int value = 0;
for (int i = 0; i < hexString.length(); i++) {
char s = hexString.charAt(i);
// 前半个字节
if (i % 2 == 0) {
value = Integer.parseInt(String.valueOf(s), 16) * 16;
} else {
// 后半个字节
value += Integer.parseInt(String.valueOf(s), 16);
array[i / 2] = (byte) value;
value = 0;
}
}
return array;
}
/**
* 获取字节高四位
* @param data
* @return
*/
public static int getHeight4(byte data){
//获取高四位
int height;
height = ((data & 0xf0) >> 4);
return height;
}
/**
* 获取字节第四位
* @param data
* @return
*/
public static int getLow4(byte data){
//获取低四位
int low;
low = (data & 0x0f);
return low;
}
/**
* 输出byte数组信息
* @param data
*/
public static void getByteString(byte[] data) {
// 输出16进制格式字符串
System.out.println("############ - 数组解析 - #############");
String result = "";
String val = "";
for (int i = 0; i < data.length; i++) {
result += (Integer.toHexString(data[i]).toUpperCase() + " ");
val = (Integer.toHexString(data[i]).toUpperCase() + " ");
System.out.println("byte数组第"+i+"位值："+val);
}
System.out.println("数组内容：" + result);
System.out.println("数组长度：" + data.length);
System.out.println("############ - 数组解析 - #############");
System.out.println("");
}
}