Android AES加密算法工具类

package com.example.aesdemo;

import java.io.UnsupportedEncodingException;
import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;
 
///** AES对称加密解密类 **/
public class AESHelper {
 
  //  /** 算法/模式/填充 **/
    private static final String CipherMode = "AES/ECB/PKCS5Padding";
 
    ///** 创建密钥 **/
    private static SecretKeySpec createKey(String password) {
        byte[] data = null;
        if (password == null) {
            password = "";
        }
        StringBuffer sb = new StringBuffer(32);
        sb.append(password);
        while (sb.length() < 32) {
            sb.append("0");
        }
        if (sb.length() > 32) {
            sb.setLength(32);
        }
 
        try {
            data = sb.toString().getBytes("UTF-8");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return new SecretKeySpec(data, "AES");
    }
 
   // /** 加密字节数据 **/
    public static byte[] encrypt(byte[] content, String password) {
        try {
            SecretKeySpec key = createKey(password);
            System.out.println(key);
            Cipher cipher = Cipher.getInstance(CipherMode);
            cipher.init(Cipher.ENCRYPT_MODE, key);
            byte[] result = cipher.doFinal(content);
            return result;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }
 
    ///** 加密(结果为16进制字符串) **/
    public static String encrypt(String content, String password) {
        byte[] data = null;
        try {
            data = content.getBytes("UTF-8");
        } catch (Exception e) {
            e.printStackTrace();
        }
        data = encrypt(data, password);
        String result = byte2hex(data);
        return result;
    }
 
  //  /** 解密字节数组 **/
    public static byte[] decrypt(byte[] content, String password) {
        try {
            SecretKeySpec key = createKey(password);
            Cipher cipher = Cipher.getInstance(CipherMode);
            cipher.init(Cipher.DECRYPT_MODE, key);
            byte[] result = cipher.doFinal(content);
            return result;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }
 
    ///** 解密16进制的字符串为字符串 **/
    public static String decrypt(String content, String password) {
        byte[] data = null;
        try {
            data = hex2byte(content);
        } catch (Exception e) {
            e.printStackTrace();
        }
        data = decrypt(data, password);
        if (data == null)
            return null;
        String result = null;
        try {
            result = new String(data, "UTF-8");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return result;
    }
 
   // /** 字节数组转成16进制字符串 **/
    public static String byte2hex(byte[] b) { // 一个字节的数，
        StringBuffer sb = new StringBuffer(b.length * 2);
        String tmp = "";
        for (int n = 0; n < b.length; n++) {
            // 整数转成十六进制表示
            tmp = (java.lang.Integer.toHexString(b[n] & 0XFF));
            if (tmp.length() == 1) {
                sb.append("0");
            }
            sb.append(tmp);
        }
        return sb.toString().toUpperCase(); // 转成大写
    }
 
  //  /** 将hex字符串转换成字节数组 **/
    private static byte[] hex2byte(String inputString) {
        if (inputString == null || inputString.length() < 2) {
            return new byte[0];
        }
        inputString = inputString.toLowerCase();
        int l = inputString.length() / 2;
        byte[] result = new byte[l];
        for (int i = 0; i < l; ++i) {
            String tmp = inputString.substring(2 * i, 2 * i + 2);
            result[i] = (byte) (Integer.parseInt(tmp, 16) & 0xFF);
        }
        return result;
    }
}

2、使用

package com.example.aesdemo;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.util.Log; 

public class MainActivity extends Activity {
		
        protected void onCreate(Bundle savedInstanceState) {
    		super.onCreate(savedInstanceState);
    		setContentView(R.layout.activity_main);
	
	        String masterPassword = "a";  
	        String originalText = "于";  

	        try {  
	            String encryptingCode = AESHelper.encrypt(originalText,masterPassword);  
//	          System.out.println("加密结果为 " + encryptingCode);  
	            Log.i("加密结果为 ",encryptingCode);  
	            String decryptingCode = AESHelper.decrypt(encryptingCode,masterPassword);  
//	            System.out.println("解密结果为 " + decryptingCode);  
	            Log.i("解密结果",decryptingCode);  
	           } catch (Exception e) {  
	            // TODO Auto-generated catch block  
	            e.printStackTrace();  
	    }  	
	}

	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// Inflate the menu; this adds items to the action bar if it is present.
		getMenuInflater().inflate(R.menu.main, menu);
		return true;
	}
}

3、打印结果

09-19 10:41:05.467: I/加密结果为(707): E55C24701F6380478E1940ADDFD08D22
09-19 10:41:05.467: I/解密结果(707): 于