字节数组 整型 字符串 十六进制 字符 之间的转换

最近在项目开发中,用到了多种类型间的转换.记录一下 

    //字节数组转换字符数组
     public static String bytetoString(byte[] by)...{
        char c[]=new char[550];
        for(int i=0;i<by.length;i++)...{
            c[i]=(char)by[i];
            System.out.println("char的字节是"+c[i]);
        }
        String str1= new String(c);
        return str1.trim();
     }
     
     
    //字节数组转换为十六进制
        public static String byteToHexString(byte[] by)
        ...{
            int len=by.length;
            String ret="0x ";
            for(int i=0;i<len;i++)
            ...{
                int a=(int)by[i];
                if(a<0) a+=256;
                String s=Integer.toHexString(a);
                if(s.length()==1)
                ...{
                    s="0"+s;
                }
                ret+=s+" ";
            }
            return ret;
        }
//一个字节数组转换为另一个字节数组
        public static byte[] changeByte(byte[] byte1,int i,int a,int j,int b,byte[] byte2)...{
        //    byte[] byExp={-35,00,-128,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,-49};
            // byte2=new byte[128];
            for(;i>=a;)...{
                for(;j<=b;j++)...{
                    byte2[j]=byte1[i];
                    i--;
                //    System.err.println(byExp[j]);
                }
            }
            return byte2;
        }
    //整型转换字节数组
        public static byte[] int2bytes(int num)
        ...{
               byte[] b=new byte[4];
               int mask=0xff;
               for(int i=0;i<4;i++)...{
                    b[i]=(byte)(num>>>(24-i*8));
               }
              return b;
        }
        //字节数组转换整型
        public static int bytes2int(byte[] b)
        ...{
                 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;
        } 
//十六进制转换字节数组
        public static byte[] hexToByte(String hexStr)...{
             byte[]   baKeyword   =   new   byte[hexStr.length()/2]; 
                for(int   i   =   0;   i   <   baKeyword.length;   i++) 
                ...{ 
                  try 
                  ...{ 
                  baKeyword[i]=(byte)(Integer.parseInt(hexStr.substring(i*2,i*2+2),16)); 
                  } 
                  catch(Exception   e) 
                  ...{ 
                  e.printStackTrace(); 
                  } 
                } 
            
            
            return baKeyword;
        }