字节[]到字符[]

Question

I am in a requirement of display raw byte data in char form, there are some issue I am stuck like for example [ 1, 32, -1, -1 ] ( byte data ) which when converted into char comes as [1, 3, 2, -, 1, - ,1]

My requirement

[ 1, 32, -1, -1 ] in char format.

Intailly

I used the command

StringBuilder buffer = new StringBuilder();
    for(int i = 0; i < byte1.length;i++){
    buffer.append(byte1[i]);
    }
char[] c = buffer.toString().toCharArray();

Didn't serve my requirement.

Then I used

char dig = (char)(((int)'0')+ (-32));

it gave an invalid output

Kindly help in my requirement. Thanks in advance

Answer 1

If you just need a printable representation:

String readable = Arrays.toString(byte1);

But as stated you need a string Array like thing for this.

Answer 2

Why you need to stick to strings, use array of char array, first append extra 0 in case its short and If your data is in byte format, use bytes1.toString() and then something like this,

public class Example {

    public static void main(String args[])
    {
        String[] byte1 = {"2","45","56","1"};
        for (int i = 0; i < byte1.length; i++) {
            if(byte1[i].length()<2){
                byte1[i] = "0"+byte1[i];
            }
        }
        char[][] chr = new char[5][10];
        StringBuilder buffer = new StringBuilder();
        for(int i = 0; i < byte1.length;i++){
               chr[i] = byte1[i].toCharArray();
        }


    for (int i = 0; i < chr.length; i++) {
            System.out.println(chr[i]);
    }
    }
}

Answer 3

Perhaps the following will work for you:

byte byte1[] = {72, 101, 108, 108, 111, 33, 92, 45, 127, -5, -23};
StringBuilder buffer = new StringBuilder();
    for(int i = 0; i < byte1.length;i++){
      if (byte1[i] >= 32 && byte1[i] != 92 && byte1[i] != 127) buffer.append((char)byte1[i]);
      else {
        String temp;
        if (byte1[i] == 92) {
          buffer.append("\\\\");
        }
        else {
          temp = String.format("\\0x%02x", byte1[i]);
          buffer.append(temp);
        }
      }
    }
System.out.println(buffer);

This will produce the output:

Hello!\\-\0x7f\0xfb\0xe9

The "representable" characters will be printed normally, the others are turned into a "escaped" hex code. The \\ gets special treatment - if you want to show hex codes with an escape backslash, then you need a backslash to escape a backslash (and to get \\\\ in the output, you need "\\\\\\\\" in the code...

I also trapped the character value 127 separately since I didn't want a DEL in the string - not sure what effect that would have depending on the environment.

If your requirement is indeed exactly as you describe, you might consider the following code (which produces exactly what you asked for):

byte byte1[] = {1, 32, -1, -1};
StringBuilder buffer = new StringBuilder();
buffer.append("[");
for(int i = 0; i < byte1.length - 1;i++){
  buffer.append(String.format("%d,", byte1[i]));
}
buffer.append(String.format("%d]", byte1[byte1.length - 1]));
System.out.println(buffer);

Output:

[1,32,-1,-1]

Notice - since some numbers require more than one character, you end up with a string that is more than 4 characters long. There is no way around that.

Answer 4

由于char字段的字符数为1个字符，因此无法在char字段中存储2个字符。