Integer 到 Java 中的两位十六进制数

Question

I need to change a integer value into 2-digit hex value in Java.Is there any way for this. Thanks

My biggest number will be 63 and smallest will be 0. I want a leading zero for small values.

Answer 1

String.format("%02X", value);

如果您按照 aristar 的建议使用X而不是x ，那么您不需要使用.toUpperCase() 。

Answer 2

Integer.toHexString(42);

Javadoc: http://docs.oracle.com/javase/6/docs/api/java/lang/Integer.html#toHexString(int)

Note that this may give you more than 2 digits, however! (An Integer is 4 bytes, so you could potentially get back 8 characters.)

Here's a bit of a hack to get your padding, as long as you are absolutely sure that you're only dealing with single-byte values (255 or less):

Integer.toHexString(0x100 | 42).substring(1)

Many more (and better) solutions at Left padding integers (non-decimal format) with zeros in Java .

Answer 3

String.format("%02X", (0xFF & value));    

Answer 4

Use Integer.toHexString() . Dont forget to pad with a leading zero if you only end up with one digit. If your integer is greater than 255 you'll get more than 2 digits.

StringBuilder sb = new StringBuilder();
sb.append(Integer.toHexString(myInt));
if (sb.length() < 2) {
    sb.insert(0, '0'); // pad with leading zero if needed
}
String hex = sb.toString();

Answer 5

If you just need to print them try this:

for(int a = 0; a < 255; a++){
    if( a % 16 == 0){
        System.out.println();
    }
    System.out.printf("%02x ", a);
}

Answer 6

i use this to get a string representing the equivalent hex value of an integer separated by space for every byte EX : hex val of 260 in 4 bytes = 00 00 01 04

    public static String getHexValString(Integer val, int bytePercision){
    StringBuilder sb = new StringBuilder();
    sb.append(Integer.toHexString(val));

    while(sb.length() < bytePercision*2){
        sb.insert(0,'0');// pad with leading zero
    }

    int l = sb.length(); // total string length before spaces
    int r = l/2; //num of rquired iterations

    for (int i=1; i < r;  i++){
        int x = l-(2*i); //space postion
        sb.insert(x, ' ');
    }
    return sb.toString().toUpperCase();         
}

public static void main(String []args){
    System.out.println("hex val of 260 in 4 bytes = " + getHexValString(260,4));
}

Answer 7

根据 GabrielOshiro 的说法，如果要将整数格式化为长度 8，请尝试此操作

String.format("0x%08X", 20) //print 0x00000014