? 【强制】必须遵守，违反本约定或将会引起严重的后果;

- [ ] 1.【强制】Activity 间的数据通信，对于数据量比较大的，避免使用 Intent + Parcelable 的方式，可以考虑 EventBus 等替代方案，以免造成 TransactionTooLargeException。

import java.security.Key; 
 
import javax.crypto.Cipher; 
import javax.crypto.SecretKeyFactory; 
import javax.crypto.spec.DESedeKeySpec; 
import javax.crypto.spec.IvParameterSpec; 
 
/** 
 * 3DES加密工具类 
 * 
 * @author liufeng 
 * @date 2012-10-11 
 */ 
public class Des3 { 
 // 密钥 
 private final static String secretKey = "liuyunqiang@lx100$#365#$"; 
 // 向量 
 private final static String iv = "01234567"; 
 // 加解密统一使用的编码方式 
 private final static String encoding = "utf-8"; 
 
 /** 
 * 3DES加密 
 * 
 * @param plainText 普通文本 
 * @return 
 * @throws Exception 
 */ 
 public static String encode(String plainText) throws Exception { 
 Key deskey = null; 
 DESedeKeySpec spec = new DESedeKeySpec(secretKey.getBytes()); 
 SecretKeyFactory keyfactory = SecretKeyFactory.getInstance("desede"); 
 deskey = keyfactory.generateSecret(spec); 
 
 Cipher cipher = Cipher.getInstance("desede/CBC/PKCS5Padding"); 
 IvParameterSpec ips = new IvParameterSpec(iv.getBytes()); 
 cipher.init(Cipher.ENCRYPT_MODE, deskey, ips); 
 byte[] encryptData = cipher.doFinal(plainText.getBytes(encoding)); 
 return Base64.encode(encryptData); 
 } 
 
 /** 
 * 3DES解密 
 * 
 * @param encryptText 加密文本 
 * @return 
 * @throws Exception 
 */ 
 public static String decode(String encryptText) throws Exception { 
 Key deskey = null; 
 DESedeKeySpec spec = new DESedeKeySpec(secretKey.getBytes()); 
 SecretKeyFactory keyfactory = SecretKeyFactory.getInstance("desede"); 
 deskey = keyfactory.generateSecret(spec); 
 Cipher cipher = Cipher.getInstance("desede/CBC/PKCS5Padding"); 
 IvParameterSpec ips = new IvParameterSpec(iv.getBytes()); 
 cipher.init(Cipher.DECRYPT_MODE, deskey, ips); 
 
 byte[] decryptData = cipher.doFinal(Base64.decode(encryptText)); 
 
 return new String(decryptData, encoding); 
 } 
}