在工作中经常遇到需要加密、解密的场景。例如用户的手机号等信息，在保存到数据库的过程中，需要对数据进行加密。取出时进行解密。

 

public class DEStool {    private String sKey;    public DEStool() {        //默认构造函数提供默认密钥        sKey = "des@#$12";    }    public DEStool(String securityKey) {        if (securityKey.length() < 8) {            throw new IllegalArgumentException("密钥长度至少8位");        }        this.sKey = securityKey;    }    private Cipher makeCipher() throws Exception{        return Cipher.getInstance("DES");    }    private SecretKey makeKeyFactory() throws Exception{        SecretKeyFactory des = SecretKeyFactory.getInstance("DES");        SecretKey secretKey = des.generateSecret(new DESKeySpec(sKey.getBytes()));        return secretKey;    }    public String encrypt(String text) throws Exception{        Cipher cipher = makeCipher();        SecretKey secretKey = makeKeyFactory();        cipher.init(Cipher.ENCRYPT_MODE, secretKey);        return new String(Base64.encodeBase64(cipher.doFinal(text.getBytes())));    }    public String decrypt(String text) throws Exception{        Cipher cipher = makeCipher();        SecretKey secretKey = makeKeyFactory();        cipher.init(Cipher.DECRYPT_MODE, secretKey);        return new String(cipher.doFinal(Base64.decodeBase64(text.getBytes())));    }    public static void main(String[] args) {        DEStool tool = new DEStool("nice1234");        String content = "中国";        System.out.println("原文内容："+content);        String encrpt = null;        try {            encrpt = tool.encrypt(content);        } catch (Exception e) {            e.printStackTrace();        }        System.out.println("加密后："+encrpt + ", 长度=" + encrpt.length());        String descript =null;        try {            descript = tool.decrypt(encrpt);        } catch (Exception e) {            e.printStackTrace();        }        System.out.println("解密后：" + descript);    }}