標籤:抽取 stat nbsp bytes str 操作 位元組數組 無符號 有符號
前言:用於處理Java基本資料的轉換及進位轉換操作工具
一、實現功能
1、int預byte互轉
2、int與byte[]互轉
3、short與byte互轉
4、short與byte[]互轉
5、16位short與byte[]互轉
6、long預byte[]互轉
7、byte[]與inputstream互轉
8、byte與String互轉
9、16進位字元轉int
10、十進位轉2進位
11、byte[]轉16進位字元
12、byte[]數組指定位置抽取byte[]
二、代碼實現
package cc.eguid.util;import java.io.ByteArrayInputStream;import java.io.ByteArrayOutputStream;import java.io.IOException;import java.io.InputStream;import java.io.UnsupportedEncodingException;import java.nio.ByteBuffer;/** * 基本資料互轉工具 * @author eguid * eguid的官網:www.eguid.cc * eguid的csdn部落格:http://blog.csdn.net/eguid_1,部落格園:http://www.cnblogs.com/eguid */public class ByteUtil {private static ByteBuffer buffer = ByteBuffer.allocate(8); /** * int轉byte * @param x * @return */ public static byte intToByte(int x) { return (byte) x; } /** * byte轉int * @param b * @return */ public static int byteToInt(byte b) { //Java的byte是有符號,通過 &0xFF轉為無符號 return b & 0xFF; } /** * byte[]轉int * @param b * @return */ public static int byteArrayToInt(byte[] b) { return b[3] & 0xFF | (b[2] & 0xFF) << 8 | (b[1] & 0xFF) << 16 | (b[0] & 0xFF) << 24; } public static int byteArrayToInt(byte[] b, int index){ return b[index+3] & 0xFF | (b[index+2] & 0xFF) << 8 | (b[index+1] & 0xFF) << 16 | (b[index+0] & 0xFF) << 24; } /** * int轉byte[] * @param a * @return */ public static byte[] intToByteArray(int a) { return new byte[] { (byte) ((a >> 24) & 0xFF), (byte) ((a >> 16) & 0xFF), (byte) ((a >> 8) & 0xFF), (byte) (a & 0xFF) }; } /** * short轉byte[] * * @param b * @param s * @param index */ public static void byteArrToShort(byte b[], short s, int index) { b[index + 1] = (byte) (s >> 8); b[index + 0] = (byte) (s >> 0); } /** * byte[]轉short * * @param b * @param index * @return */ public static short byteArrToShort(byte[] b, int index) { return (short) (((b[index + 0] << 8) | b[index + 1] & 0xff)); } /** * 16位short轉byte[] * * @param s * short * @return byte[] * */ public static byte[] shortToByteArr(short s) { byte[] targets = new byte[2]; for (int i = 0; i < 2; i++) { int offset = (targets.length - 1 - i) * 8; targets[i] = (byte) ((s >>> offset) & 0xff); } return targets; } /** * byte[]轉16位short * @param b * @return */ public static short byteArrToShort(byte[] b){ return byteArrToShort(b,0); } /** * long轉byte[] * @param x * @return */ public static byte[] longToBytes(long x) { buffer.putLong(0, x); return buffer.array(); } /** * byte[]轉Long * @param bytes * @return */ public static long bytesToLong(byte[] bytes) { buffer.put(bytes, 0, bytes.length); buffer.flip();//need flip return buffer.getLong(); } /** * 從byte[]中抽取新的byte[] * @param data - 中繼資料 * @param start - 開始位置 * @param end - 結束位置 * @return 新byte[] */ public static byte[] getByteArr(byte[]data,int start ,int end){byte[] ret=new byte[end-start];for(int i=0;(start+i)<end;i++){ret[i]=data[start+i];} return ret;}/** * 流轉換為byte[] * @param inStream * @return */public static byte[] readInputStream(InputStream inStream) {ByteArrayOutputStream outStream = null;try {outStream = new ByteArrayOutputStream();byte[] buffer = new byte[1024];byte[] data = null;int len = 0;while ((len = inStream.read(buffer)) != -1) {outStream.write(buffer, 0, len);}data = outStream.toByteArray();return data;}catch (IOException e) {return null;} finally {try {if (outStream != null) {outStream.close();}if (inStream != null) {inStream.close();}} catch (IOException e) {return null;}}}/** * byte[]轉inputstream * @param b * @return */public static InputStream readByteArr(byte[] b){return new ByteArrayInputStream(b);}/** * byte數組內數字是否相同 * @param s1 * @param s2 * @return */public static boolean isEq(byte[] s1,byte[] s2){int slen=s1.length;if(slen==s2.length){for(int index=0;index<slen;index++){if(s1[index]!=s2[index]){return false;}}return true;}return false;}/** * byte數群組轉換為Stirng * @param s1 -數組 * @param encode -字元集 * @param err -轉換錯誤時返回該文字 * @return */public static String getString(byte[] s1,String encode,String err){try {return new String(s1,encode);} catch (UnsupportedEncodingException e) {return err==null?null:err;}}/** * byte數群組轉換為Stirng * @param s1-數組 * @param encode-字元集 * @return */public static String getString(byte[] s1,String encode){return getString(s1,encode,null);}//測試public static void main(String []args){System.err.println(isEq(new byte[]{1,2},new byte[]{1,2}));}/** * 位元組數組轉16進位字串 * @param b * @return */public static String byteArrToHexString(byte[] b){ String result=""; for (int i=0; i < b.length; i++) { result += Integer.toString( ( b[i] & 0xff ) + 0x100, 16).substring(1); } return result;}/** * 16進位字元創轉int * @param hexString * @return */public static int hexStringToInt(String hexString){return Integer.parseInt(hexString,16);}/** * 十進位轉二進位 * @param i * @return */public static String intToBinary(int i){return Integer.toBinaryString(i);}}
最全面的Java位元組byte操作,處理Java基本資料的轉換及進位轉換操作工具,流媒體及java底層開發項目常用工具類