Android上使用AES加密和解密字符串

废话少说，直接上类的源码

import android.util.Base64;
import java.nio.charset.StandardCharsets;
import java.util.Objects;
import java.util.Random;
import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;
import javax.crypto.spec.IvParameterSpec;

public class Encrypt {
    
    

    private static final String CBC_PKCS5_PADDING = "AES/CBC/PKCS5Padding";
    private static final String AES = "AES";
    private static String IvParameter = "";
    private static String key = "";

    public static String encrypt(String data) {
    
    
        return encryptString(data);
    }

    public static String encrypt(int data) {
    
    
        return encryptString(Integer.toString(data));
    }

    public static String encrypt(Long data) {
    
    
        return encryptString(data.toString());
    }

    public static String encrypt(CharSequence data) {
    
    
        return encryptString(data.toString());
    }

    public static String encrypt() {
    
    
        return "";
    }

    private static String encryptString(String data) {
    
    
        try {
    
    
            byte[] raw = key.getBytes();
            SecretKeySpec skeySpec = new SecretKeySpec(raw, AES);
            Cipher cipher = Cipher.getInstance(CBC_PKCS5_PADDING);
            cipher.init(Cipher.ENCRYPT_MODE, skeySpec, new IvParameterSpec(IvParameter.getBytes()));
            byte[] cipherText = cipher.doFinal(data.getBytes());
            return Base64.encodeToString(cipherText, Base64.DEFAULT)
                    .replaceAll(Objects.requireNonNull(System.getProperty("line.separator")), "");
        } catch (Exception e) {
    
    
            e.printStackTrace();
        }
        return "";
    }

    public static String decrypt() {
    
    
        return "";
    }

    public static String decrypt(String data) {
    
    
        try {
    
    
            byte[] raw = key.getBytes(StandardCharsets.US_ASCII);
            SecretKeySpec skeySpec = new SecretKeySpec(raw, AES);
            Cipher cipher = Cipher.getInstance(CBC_PKCS5_PADDING);
            cipher.init(Cipher.DECRYPT_MODE, skeySpec, new IvParameterSpec(IvParameter.getBytes()));
            return new String(cipher.doFinal(Base64.decode(data, Base64.DEFAULT)));
        } catch (Exception e) {
    
    
            e.printStackTrace();
        }
        return "";
    }

    public static void initUtil() {
    
    
        Random random = new Random();
        StringBuilder key_cache = new StringBuilder(), IvParameter_cache = new StringBuilder();
        String text = "abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
        for (int i = 0; i < 16; i++)
            key_cache.append(text.charAt(random.nextInt(text.length())));
        for (int i = 0; i < 16; i++)
            IvParameter_cache.append(text.charAt(random.nextInt(text.length())));
        IvParameter = IvParameter_cache.toString();
        key = key_cache.toString();
    }

    public static void setSecretKey(String secretKey) {
    
    
        key = secretKey;
    }

    public static void setIvParameter(String ivParameter) {
    
    
        IvParameter = ivParameter;
    }

    public static String getSecretKey() {
    
    
        return key;
    }

    public static String getIvParameter() {
    
    
        return IvParameter;
    }
}

这个类的使用简单且高效
我们需要初始化AES密钥和偏移量
因此我们仅需要使用下面的代码

Encrypt.initUtil();
//随机生成AES密钥和偏移量
String key = Encrypt.getSecretKey();
//需要密钥才能解密字符串
String IvParameter = Encrypt.getIvParameter();
//因此两个数据必须保存才能解密字符串

加密的过程十分简单,你仅需一行代码即可加密字符串(需要初始化)

Log.d("Encrypt.test",Encrypt.encrypt("Hello World!"));
//返回加密后的字符串
Log.d("Encrypt.test",Encrypt.encrypt());
//当数据为空时,将会返回空字符串
//注意,Logcat中不会打印空字符串的内容

这样你会在Logcat控制台中看到以下打印出的数据

 D  Uj+FXzJqjeWpCC4H04HvJA==

解密也很简单

Log.d("Encrypt.test",Encrypt.decrypt("Hello World!"));
//返回解密后的字符串
Log.d("Encrypt.test",Encrypt.decrypt());
//当数据为空时,将会返回空字符串
//注意,Logcat中不会打印空字符串的内容

Logcat控制台中打印出的数据(需要保持同一个密钥和偏移量)

 D  Hello World!

如果先前生成了密钥和偏移量,需要设置一下即可正常使用

Encrypt.setSecretKey(KEY);
Encrypt.getIvParameter(IvParameter);