i don't know what i did

autojs/src/main/java/com/stardust/autojs/runtime/api/crypto/Crypto.java

@@ -0,0 +1,28 @@
+package com.stardust.autojs.runtime.api.crypto;
+
+import java.security.InvalidKeyException;
+import java.security.NoSuchAlgorithmException;
+import java.security.SecureRandom;
+
+import javax.crypto.Cipher;
+import javax.crypto.KeyGenerator;
+import javax.crypto.NoSuchPaddingException;
+import javax.crypto.SecretKey;
+
+import static javax.crypto.Cipher.ENCRYPT_MODE;
+
+/**
+ * Created by Stardust on 2017/9/20.
+ */
+
+public class Crypto {
+
+    public Cipher createCipher(String algorithm, String password) throws InvalidKeyException, NoSuchAlgorithmException, NoSuchPaddingException {
+        javax.crypto.Cipher cipher = javax.crypto.Cipher.getInstance(algorithm);
+        KeyGenerator keyGenerator = KeyGenerator.getInstance(algorithm);
+        keyGenerator.init(128, new SecureRandom(password.getBytes()));
+        SecretKey secretKey = keyGenerator.generateKey();
+        cipher.init(ENCRYPT_MODE, secretKey);
+        return cipher;
+    }
+}