我正在尝试将类似“testing123”的字符串转换为java中的十六进制形式。我目前正在使用 BlueJ。
并且将其转换回来,除了向后之外,它是一样的吗?
这是将其转换为十六进制的简短方法:
public String toHex(String arg) {
return String.format("%040x", new BigInteger(1, arg.getBytes(/*YOUR_CHARSET?*/)));
}
为确保十六进制的长度始终为 40 个字符,BigInteger 必须为正数:
public String toHex(String arg) {
return String.format("%x", new BigInteger(1, arg.getBytes(/*YOUR_CHARSET?*/)));
}
import org.apache.commons.codec.binary.Hex;
...
String hexString = Hex.encodeHexString(myString.getBytes(/* charset */));
http://commons.apache.org/codec/apidocs/org/apache/commons/codec/binary/Hex.html
编码为十六进制的数字必须代表字符的某种编码,例如 UTF-8。因此,首先将 String 转换为代表该编码中字符串的 byte[],然后将每个字节转换为十六进制。
public static String hexadecimal(String input, String charsetName) throws UnsupportedEncodingException {
if (input == null) throw new NullPointerException();
return asHex(input.getBytes(charsetName));
}
private static final char[] HEX_CHARS = "0123456789abcdef".toCharArray();
public static String asHex(byte[] buf)
{
char[] chars = new char[2 * buf.length];
for (int i = 0; i < buf.length; ++i)
{
chars[2 * i] = HEX_CHARS[(buf[i] & 0xF0) >>> 4];
chars[2 * i + 1] = HEX_CHARS[buf[i] & 0x0F];
}
return new String(chars);
}
使用DatatypeConverter.printHexBinary()
:
public static String toHexadecimal(String text) throws UnsupportedEncodingException
{
byte[] myBytes = text.getBytes("UTF-8");
return DatatypeConverter.printHexBinary(myBytes);
}
示例用法:
System.out.println(toHexadecimal("Hello StackOverflow"));
印刷:
48656C6C6F20537461636B4F766572666C6F77
注意:这会导致一些额外的麻烦Java 9
和更新,因为默认情况下不包含 API。供参考,例如看到这个 GitHub
问题。
这是另一个解决方案
public static String toHexString(byte[] ba) {
StringBuilder str = new StringBuilder();
for(int i = 0; i < ba.length; i++)
str.append(String.format("%x", ba[i]));
return str.toString();
}
public static String fromHexString(String hex) {
StringBuilder str = new StringBuilder();
for (int i = 0; i < hex.length(); i+=2) {
str.append((char) Integer.parseInt(hex.substring(i, i + 2), 16));
}
return str.toString();
}
所有基于 String.getBytes() 的答案都涉及根据字符集对字符串进行编码。您不一定要获得构成字符串的 2 字节字符的十六进制值。如果您真正想要的是相当于十六进制查看器,那么您需要直接访问字符。这是我在代码中用于调试 Unicode 问题的函数:
static String stringToHex(String string) {
StringBuilder buf = new StringBuilder(200);
for (char ch: string.toCharArray()) {
if (buf.length() > 0)
buf.append(' ');
buf.append(String.format("%04x", (int) ch));
}
return buf.toString();
}
然后, stringToHex("testing123") 会给你:
0074 0065 0073 0074 0069 006e 0067 0031 0032 0033
获取十六进制的整数值
//hex like: 0xfff7931e to int
int hexInt = Long.decode(hexString).intValue();
我会建议这样的事情,str
你的输入字符串在哪里:
StringBuffer hex = new StringBuffer();
char[] raw = tokens[0].toCharArray();
for (int i=0;i<raw.length;i++) {
if (raw[i]<=0x000F) { hex.append("000"); }
else if(raw[i]<=0x00FF) { hex.append("00" ); }
else if(raw[i]<=0x0FFF) { hex.append("0" ); }
hex.append(Integer.toHexString(raw[i]).toUpperCase());
}
byte[] bytes = string.getBytes(CHARSET); // you didn't say what charset you wanted
BigInteger bigInt = new BigInteger(bytes);
String hexString = bigInt.toString(16); // 16 is the radix
您可以hexString
在此时返回,但需要注意的是前导空字符将被剥离,如果第一个字节小于 16,则结果将具有奇数长度。如果您需要处理这些情况,您可以添加一些额外的代码用 0 填充:
StringBuilder sb = new StringBuilder();
while ((sb.length() + hexString.length()) < (2 * bytes.length)) {
sb.append("0");
}
sb.append(hexString);
return sb.toString();
转换十六进制代码中的字母和字母中的十六进制代码。
String letter = "a";
String code;
int decimal;
code = Integer.toHexString(letter.charAt(0));
decimal = Integer.parseInt(code, 16);
System.out.println("Hex code to " + letter + " = " + code);
System.out.println("Char to " + code + " = " + (char) decimal);
换一种方式(十六进制到字符串),您可以使用
public String hexToString(String hex) {
return new String(new BigInteger(hex, 16).toByteArray());
}
首先使用 getBytes() 函数将其转换为字节,然后将其转换为十六进制 ussign this :
private static String hex(byte[] bytes) {
StringBuilder sb = new StringBuilder();
for (int i=0; i<bytes.length; i++) {
sb.append(String.format("%02X ",bytes[i]));
}
return sb.toString();
}
没有外部库的一行 HEX 编码/解码(Java 8 及更高版本):
编码:
String hexString = inputString.chars().mapToObj(c ->
Integer.toHexString(c)).collect(Collectors.joining());
解码:
String decodedString = Stream.iterate(0, i -> i+2)
.limit(hexString.length()/2 + Math.min(hexString.length()%2,1))
.map(i -> "" + (char)Integer.parseInt("" + hexString.charAt(i) + hexString.charAt(i+1),16))
.collect(Collectors.joining());
使用来自多个线程的多人帮助..
我知道这已经得到解答,但我想为我遇到同样情况的任何其他人提供一个完整的编码和解码方法..
这是我的编码和解码方法..
// Global Charset Encoding
public static Charset encodingType = StandardCharsets.UTF_8;
// Text To Hex
public static String textToHex(String text)
{
byte[] buf = null;
buf = text.getBytes(encodingType);
char[] HEX_CHARS = "0123456789abcdef".toCharArray();
char[] chars = new char[2 * buf.length];
for (int i = 0; i < buf.length; ++i)
{
chars[2 * i] = HEX_CHARS[(buf[i] & 0xF0) >>> 4];
chars[2 * i + 1] = HEX_CHARS[buf[i] & 0x0F];
}
return new String(chars);
}
// Hex To Text
public static String hexToText(String hex)
{
int l = hex.length();
byte[] data = new byte[l / 2];
for (int i = 0; i < l; i += 2)
{
data[i / 2] = (byte) ((Character.digit(hex.charAt(i), 16) << 4)
+ Character.digit(hex.charAt(i + 1), 16));
}
String st = new String(data, encodingType);
return st;
}
将字符串转换为十六进制:
public String hexToString(String hex) {
return Integer.toHexString(Integer.parseInt(hex));
}
这绝对是最简单的方法。
好多了:
public static String fromHexString(String hex, String sourceEncoding ) throws IOException{
ByteArrayOutputStream bout = new ByteArrayOutputStream();
byte[] buffer = new byte[512];
int _start=0;
for (int i = 0; i < hex.length(); i+=2) {
buffer[_start++] = (byte)Integer.parseInt(hex.substring(i, i + 2), 16);
if (_start >=buffer.length || i+2>=hex.length()) {
bout.write(buffer);
Arrays.fill(buffer, 0, buffer.length, (byte)0);
_start = 0;
}
}
return new String(bout.toByteArray(), sourceEncoding);
}
import java.io.*;
import java.util.*;
public class Exer5{
public String ConvertToHexadecimal(int num){
int r;
String bin="\0";
do{
r=num%16;
num=num/16;
if(r==10)
bin="A"+bin;
else if(r==11)
bin="B"+bin;
else if(r==12)
bin="C"+bin;
else if(r==13)
bin="D"+bin;
else if(r==14)
bin="E"+bin;
else if(r==15)
bin="F"+bin;
else
bin=r+bin;
}while(num!=0);
return bin;
}
public int ConvertFromHexadecimalToDecimal(String num){
int a;
int ctr=0;
double prod=0;
for(int i=num.length(); i>0; i--){
if(num.charAt(i-1)=='a'||num.charAt(i-1)=='A')
a=10;
else if(num.charAt(i-1)=='b'||num.charAt(i-1)=='B')
a=11;
else if(num.charAt(i-1)=='c'||num.charAt(i-1)=='C')
a=12;
else if(num.charAt(i-1)=='d'||num.charAt(i-1)=='D')
a=13;
else if(num.charAt(i-1)=='e'||num.charAt(i-1)=='E')
a=14;
else if(num.charAt(i-1)=='f'||num.charAt(i-1)=='F')
a=15;
else
a=Character.getNumericValue(num.charAt(i-1));
prod=prod+(a*Math.pow(16, ctr));
ctr++;
}
return (int)prod;
}
public static void main(String[] args){
Exer5 dh=new Exer5();
Scanner s=new Scanner(System.in);
int num;
String numS;
int choice;
System.out.println("Enter your desired choice:");
System.out.println("1 - DECIMAL TO HEXADECIMAL ");
System.out.println("2 - HEXADECIMAL TO DECIMAL ");
System.out.println("0 - EXIT ");
do{
System.out.print("\nEnter Choice: ");
choice=s.nextInt();
if(choice==1){
System.out.println("Enter decimal number: ");
num=s.nextInt();
System.out.println(dh.ConvertToHexadecimal(num));
}
else if(choice==2){
System.out.println("Enter hexadecimal number: ");
numS=s.next();
System.out.println(dh.ConvertFromHexadecimalToDecimal(numS));
}
}while(choice!=0);
}
}
new BigInteger(1, myString.getBytes(/*YOUR_CHARSET?*/)).toString(16)
以下是一些比较不同方法和库的基准。Guava 在解码方面击败了 Apache Commons Codec。Commons Codec 在编码方面击败了 Guava。JHex 在解码和编码方面都击败了他们。
String hexString = "596f752772652077656c636f6d652e";
byte[] decoded = JHex.decodeChecked(hexString);
System.out.println(new String(decoded));
String reEncoded = JHex.encode(decoded);
一切都在JHex 的单个类文件中。如果您不想在依赖关系树中再添加一个库,请随意复制粘贴。另请注意,在我弄清楚如何使用 Gradle 和 Bintray 插件发布多个发布目标之前,它只能作为 Java 9 jar 使用。
检查此解决方案的 String to hex 和 hex to String 反之亦然
public class TestHexConversion {
public static void main(String[] args) {
try{
String clearText = "testString For;0181;with.love";
System.out.println("Clear Text = " + clearText);
char[] chars = clearText.toCharArray();
StringBuffer hex = new StringBuffer();
for (int i = 0; i < chars.length; i++) {
hex.append(Integer.toHexString((int) chars[i]));
}
String hexText = hex.toString();
System.out.println("Hex Text = " + hexText);
String decodedText = HexToString(hexText);
System.out.println("Decoded Text = "+decodedText);
} catch (Exception e){
e.printStackTrace();
}
}
public static String HexToString(String hex){
StringBuilder finalString = new StringBuilder();
StringBuilder tempString = new StringBuilder();
for( int i=0; i<hex.length()-1; i+=2 ){
String output = hex.substring(i, (i + 2));
int decimal = Integer.parseInt(output, 16);
finalString.append((char)decimal);
tempString.append(decimal);
}
return finalString.toString();
}
输出如下:
明文 = testString For;0181;with.love
十六进制文本 = 74657374537472696e6720466f723b303138313b776974682e6c6f7665
解码文本 = testString For;0181;with.love
A short and convenient way to convert a String to its Hexadecimal notation is:
public static void main(String... args){
String str = "Hello! This is test string.";
char ch[] = str.toCharArray();
StringBuilder sb = new StringBuilder();
for (int i = 0; i < ch.length; i++) {
sb.append(Integer.toHexString((int) ch[i]));
}
System.out.println(sb.toString());
}