Base64 encryption and decryption
Normally, encryption is basically always accompanied by decryption. The so-called encryption or decryption often requires some rules. A new set of encryption processing classes, Base64 processing, has been provided since JDK1.8. There are two internal classes in this class:
- Base64.Encoder: perform encryption processing;
- public byte[] encode(byte[] src) Use the Base64 encoding scheme to encode all the bytes in the specified byte array into the newly allocated byte array
- Base64.Decoder: Perform decryption processing;
- public byte[] decode(byte[] src): Use the Base64 encoding scheme to decode all bytes in the input byte array, and write the result to the newly allocated output byte array.
Example: Implement encryption and decryption operations
package 开发支持类库;
import java.util.Base64;
public class Base64类 {
public static void main(String[] args) {
//加密
String msg = "加密内容"; //要发送的信息内容
//getEncoder()返回一个Base64编码方案，encode利用此方法进行加密
byte[] enMsg = Base64.getEncoder().encode(msg.getBytes()); //数据加密
String enString = new String(enMsg); //转换为String
System.out.println("加密后："+enString);
//解密
byte[] deMsg = Base64.getDecoder().decode(enMsg); //解密，getDecoder()返回一个Base64编码方案，decode进行解密
String deString = new String(deMsg);
System.out.println("解密结果："+deString);
}
}
After encryption: vNPD3MTayN0=
Decryption result: encrypted content
Although Base64 can implement encryption and decryption processing, because it is a public version of the algorithm, it is often not safe to directly encrypt data, so the best way is to use salt operation .
String salt = "javaDemo"; //定义盐值
String msg = "加密内容"+"{"+salt+"}"; //加上了盐值，数据不只有加密内容Even if the salt actually finds that the effect of encryption is not very good, the best way is to encrypt multiple times.
Example: complex encryption operation
package 开发支持类库;
import java.util.Base64;
public class Base64类 {
public static void main(String[] args) {
//加密
String str =StringUtil.encode("加密内容") ;
System.out.println(str);
//解密
str = StringUtil.decode(str);
System.out.println(str);
}
}
class StringUtil{
private static final String SALT = "盐值"; //公共的盐值
private static final int RPEAT = 3; //加密次数
/**
* 加密处理
* @param str 要加密的字符串，需要与盐值整合
* @return 加密后的数据
*/
public static String encode(String str) { //加密处理
String temp = str +"{"+SALT+"}"; //盐值对外不公布
byte data[] = temp.getBytes(); //将字符串变为字节数组
for(int x = 0;x <RPEAT ;x++) {
data = Base64.getEncoder().encode(data); //重复加密
}
return new String(data); //字节数组转为字符串，返回加密结果
}
/**
* 解密处理
* @param str 解密的字符串
* @return 解密后的内容
*/
public static String decode(String str) {
byte data[] = str.getBytes();//将字符串变为字节数组
for(int x = 0;x <RPEAT ;x++) {
data = Base64.getDecoder().decode(data); //重复解密，之前加密多少次就解密多少次
}
return new String(data).replaceAll("\\{\\S+\\}", "");//S表示任何非空格的字符,将括号和里面所有内容替换成null,字节数组转为字符串，返回解密结果
}
}
ZGs1UVJETk5WR0Y1VGpFM01HTTNWM1JZTUQwPQ==
encrypted content
It is best to use 2-3 encryption programs and find some encryption methods that are completely undecryptable.