试试这个方法:

byte bv = 10;
String hexString = Integer.toHexString(bv);

处理数组(如果我没理解错的话):

byte[] bytes = {9, 10, 11, 15, 16};
StringBuffer result = new StringBuffer();
for (byte b : bytes) {
    result.append(String.format("%02X ", b));
    result.append(" "); // delimiter
}
return result.toString();

正如polygeneluants所提到的，String.format()是与Integer.toHexString()相比的正确答案(因为它以正确的方式处理负数)。

如果你想要一个恒定宽度的十六进制表示，即0A而不是a，这样你就可以明确地恢复字节，尝试format():

StringBuilder result = new StringBuilder();
for (byte bb : byteArray) {
    result.append(String.format("%02X", bb));
}
return result.toString();

最好的解决方案是这样的一句话:

String hex=DatatypeConverter.printHexBinary(byte[] b);

正如这里提到的

试试这个方法:

byte bv = 10;
String hexString = Integer.toHexString(bv);

处理数组(如果我没理解错的话):

byte[] bytes = {9, 10, 11, 15, 16};
StringBuffer result = new StringBuffer();
for (byte b : bytes) {
    result.append(String.format("%02X ", b));
    result.append(" "); // delimiter
}
return result.toString();

正如polygeneluants所提到的，String.format()是与Integer.toHexString()相比的正确答案(因为它以正确的方式处理负数)。

这是一条非常快的路。不需要外部库。

final protected static char[] HEXARRAY = "0123456789abcdef".toCharArray();

    public static String encodeHexString( byte[] bytes ) {

        char[] hexChars = new char[bytes.length * 2];
        for (int j = 0; j < bytes.length; j++) {
            int v = bytes[j] & 0xFF;
            hexChars[j * 2] = HEXARRAY[v >>> 4];
            hexChars[j * 2 + 1] = HEXARRAY[v & 0x0F];
        }
        return new String(hexChars);
    }

我所发现的最快的方法是:

private static final String    HEXES    = "0123456789ABCDEF";

static String getHex(byte[] raw) {
    final StringBuilder hex = new StringBuilder(2 * raw.length);
    for (final byte b : raw) {
        hex.append(HEXES.charAt((b & 0xF0) >> 4)).append(HEXES.charAt((b & 0x0F)));
    }
    return hex.toString();
}

它比String.format快50倍。如果你想测试它:

public class MyTest{
    private static final String    HEXES        = "0123456789ABCDEF";

    @Test
    public void test_get_hex() {
        byte[] raw = {
            (byte) 0xd0, (byte) 0x0b, (byte) 0x01, (byte) 0x2a, (byte) 0x63,
            (byte) 0x78, (byte) 0x01, (byte) 0x2e, (byte) 0xe3, (byte) 0x6c,
            (byte) 0xd2, (byte) 0xb0, (byte) 0x78, (byte) 0x51, (byte) 0x73,
            (byte) 0x34, (byte) 0xaf, (byte) 0xbb, (byte) 0xa0, (byte) 0x9f,
            (byte) 0xc3, (byte) 0xa9, (byte) 0x00, (byte) 0x1e, (byte) 0xd5,
            (byte) 0x4b, (byte) 0x89, (byte) 0xa3, (byte) 0x45, (byte) 0x35,
            (byte) 0xd6, (byte) 0x10,
        };

        int N = 77777;
        long t;

        {
            t = System.currentTimeMillis();
            for (int i = 0; i < N; i++) {
                final StringBuilder hex = new StringBuilder(2 * raw.length);
                for (final byte b : raw) {
                    hex.append(HEXES.charAt((b & 0xF0) >> 4)).append(HEXES.charAt((b & 0x0F)));
                }
                hex.toString();
            }
            System.out.println(System.currentTimeMillis() - t); // 50
        }

        {
            t = System.currentTimeMillis();
            for (int i = 0; i < N; i++) {
                StringBuilder hex = new StringBuilder(2 * raw.length);
                for (byte b : raw) {
                    hex.append(String.format("%02X", b));
                }
                hex.toString();
            }
            System.out.println(System.currentTimeMillis() - t); // 2535
        }

    }
}

编辑:刚刚发现一些东西只是稍微快一点，保持在一行，但与JRE 9不兼容。使用风险自负

import javax.xml.bind.DatatypeConverter;

DatatypeConverter.printHexBinary(raw);