CryptUtil.java

CryptUtil.java

CryptUtil.java

import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;

public class CryptUtil {

    private static String toHex(byte[] bytes) {
        StringBuilder buffer = new StringBuilder(bytes.length * 2);
        String str;
        for (Byte b : bytes) {
            str = Integer.toHexString(b);
            int len = str.length();
            if (len == 8) {
                buffer.append(str.substring(6));
            } else if (len == 2) {
                buffer.append(str);
            } else {
                buffer.append("0").append(str);
            }
        }
        return buffer.toString();
    }

    private static byte[] fromHex(String text) {
        byte[] arr = new byte[text.length() / 2];
        for (int i = 0; i < text.length(); i += 2) {
            arr[i / 2] = (byte) Integer.parseInt(text.substring(i, i + 2), 16);
        }
        return arr;
    }

    public static String encrypt(String text, String key) {
        try {
            Cipher cipher = Cipher.getInstance("AES");
            SecretKeySpec skeySpec = new SecretKeySpec(key.getBytes(), "AES");
            cipher.init(Cipher.ENCRYPT_MODE, skeySpec);
            return toHex(cipher.doFinal(text.getBytes()));
        } catch (Exception e) {
            return null;
        }
    }

    public static String decrypt(String text, String key) {
        try {
            Cipher cipher = Cipher.getInstance("AES");
            SecretKeySpec skeySpec = new SecretKeySpec(key.getBytes(), "AES");
            cipher.init(Cipher.DECRYPT_MODE, skeySpec);
            return new String(cipher.doFinal(fromHex(text)));
        } catch (Exception e) {
            return null;
        }
    }
}