Java comes with MessageDigest to implement the md5 encryption algorithm for text
- 2020-04-01 04:34:18
- OfStack
This article USES Java's built-in MessageDigest to implement the md5 encryption algorithm for the text, the specific code is as follows:
package cn.yicha.novel.util;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
public class ParseMD5 {
public static String parseStrToMd5L32(String str){
String reStr = null;
try {
MessageDigest md5 = MessageDigest.getInstance("MD5");
byte[] bytes = md5.digest(str.getBytes());
StringBuffer stringBuffer = new StringBuffer();
for (byte b : bytes){
int bt = b&0xff;
if (bt < 16){
stringBuffer.append(0);
}
stringBuffer.append(Integer.toHexString(bt));
}
reStr = stringBuffer.toString();
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
return reStr;
}
public static String parseStrToMd5U32(String str){
String reStr = parseStrToMd5L32(str);
if (reStr != null){
reStr = reStr.toUpperCase();
}
return reStr;
}
public static String parseStrToMd5U16(String str){
String reStr = parseStrToMd5L32(str);
if (reStr != null){
reStr = reStr.toUpperCase().substring(8, 24);
}
return reStr;
}
public static String parseStrToMd5L16(String str){
String reStr = parseStrToMd5L32(str);
if (reStr != null){
reStr = reStr.substring(8, 24);
}
return reStr;
}
}
The second case: In the process of Java software development, it is inevitable that some data will be encrypted, so Java provides its own implementation of MessageDigest text encryption algorithm, the following is a code example of the MD5 encryption tool class for text encryption:
MD5 encryption algorithm in Java The full version:
package net.yuerwan.commons.util;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import org.apache.commons.lang.StringUtils;
public class MD5Util {
public static String textToMD5L32(String plainText){
String result = null;
//First determine whether it is null
if(StringUtils.isBlank(plainText)){
return null;
}
try{
//It is first instantiated and initialized
MessageDigest md = MessageDigest.getInstance("MD5");
//Gets an array of bytes in the operating system's default byte encoding format
byte[] btInput = plainText.getBytes();
//The resulting byte array is processed
md.update(btInput);
//Perform the hash calculation and return the result
byte[] btResult = md.digest();
//Length of data after hash calculation
StringBuffer sb = new StringBuffer();
for(byte b : btResult){
int bt = b&0xff;
if(bt<16){
sb.append(0);
}
sb.append(Integer.toHexString(bt));
}
result = sb.toString();
}catch(NoSuchAlgorithmException e){
e.printStackTrace();
}
return result;
}
public static String textToMD5U32(String plainText){
if(StringUtils.isBlank(plainText)){
return null;
}
String result = textToMD5L32(plainText);
return result.toUpperCase();
}
The third case: Java implementation of MD5 encryption algorithm
package other;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
public class MD5 {
//Global array
private final static String[] strDigits = { "0", "1", "2", "3", "4", "5",
"6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };
public MD5() {
}
//Returns a number and a string
private static String byteToArrayString(byte bByte) {
int iRet = bByte;
// System.out.println("iRet="+iRet);
if (iRet < 0) {
iRet += 256;
}
int iD1 = iRet / 16;
int iD2 = iRet % 16;
return strDigits[iD1] + strDigits[iD2];
}
//Return form only for Numbers
private static String byteToNum(byte bByte) {
int iRet = bByte;
System.out.println("iRet1=" + iRet);
if (iRet < 0) {
iRet += 256;
}
return String.valueOf(iRet);
}
//Converts the byte array to a hexadecimal string
private static String byteToString(byte[] bByte) {
StringBuffer sBuffer = new StringBuffer();
for (int i = 0; i < bByte.length; i++) {
sBuffer.append(byteToArrayString(bByte[i]));
}
return sBuffer.toString();
}
public static String GetMD5Code(String strObj) {
String resultString = null;
try {
resultString = new String(strObj);
MessageDigest md = MessageDigest.getInstance("MD5");
//The function md.digest() returns a byte array of hash results
resultString = byteToString(md.digest(strObj.getBytes()));
} catch (NoSuchAlgorithmException ex) {
ex.printStackTrace();
}
return resultString;
}
public static void main(String[] args) {
MD5 getMD5 = new MD5();
System.out.println(getMD5.GetMD5Code("000000"));
}
}