java AES算法

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/**
 * 
 *
 */
package com.rsa;

import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.security.spec.AlgorithmParameterSpec;

import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.KeyGenerator;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;
import javax.crypto.spec.IvParameterSpec;

public class AESEncrypter {
    public static byte[] iv = new byte[] { 82, 22, 50, 44, -16, 124, -40, -114, -87, -40, 37, 23, -56, 23, -33, 75 };

    private static AESEncrypter aes = null;

    public static byte[] key1 = new byte[] { -42, 35, 67, -86, 19, 29, -11, 84, 94, 111, 75, -104, 71, 46, 86, -21, -119, 110, -11, -32, -28, 91, -33, -46, 99, 49, 2, 66, -101, -11, -8, 56 };

    private AESEncrypter() {

    }

    public static synchronized AESEncrypter getInstance() {
        if (aes == null) {
            aes = new AESEncrypter();
        }
        return aes;
    }

    public String encrypt(String msg) {

        String str = "";
        try {
            KeyGenerator kgen = KeyGenerator.getInstance("AES");
            kgen.init(128, new SecureRandom(key1));
            AlgorithmParameterSpec paramSpec = new IvParameterSpec(iv);
            SecretKey key = kgen.generateKey();
            Cipher ecipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
            ecipher.init(Cipher.ENCRYPT_MODE, key, paramSpec);
            str = asHex(ecipher.doFinal(msg.getBytes()));
        } catch (BadPaddingException e) {
            e.printStackTrace();
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        } catch (NoSuchPaddingException e) {
            e.printStackTrace();
        } catch (InvalidKeyException e) {
            e.printStackTrace();
        } catch (InvalidAlgorithmParameterException e) {
            e.printStackTrace();
        } catch (IllegalBlockSizeException e) {
            e.printStackTrace();
        }
        return str;
    }

    public String decrypt(String value) {
        try {
            KeyGenerator kgen = KeyGenerator.getInstance("AES");
            kgen.init(128, new SecureRandom(key1));
            AlgorithmParameterSpec paramSpec = new IvParameterSpec(iv);
            SecretKey key = kgen.generateKey();
            Cipher dcipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
            dcipher.init(Cipher.DECRYPT_MODE, key, paramSpec);
            return new String(dcipher.doFinal(asBin(value)));
        } catch (BadPaddingException e) {
            e.printStackTrace();
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        } catch (NoSuchPaddingException e) {
            e.printStackTrace();
        } catch (InvalidKeyException e) {
            e.printStackTrace();
        } catch (InvalidAlgorithmParameterException e) {
            e.printStackTrace();
        } catch (IllegalBlockSizeException e) {
            e.printStackTrace();
        }
        return "";
    }

    private String asHex(byte buf[]) {
        StringBuffer strbuf = new StringBuffer(buf.length * 2);
        int i;

        for (i = 0; i < buf.length; i++) {
            if (((int) buf[i] & 0xff) < 0x10)
                strbuf.append("0");

            strbuf.append(Long.toString((int) buf[i] & 0xff, 16));
        }

        return strbuf.toString();
    }

    private byte[] asBin(String src) {
        if (src.length() < 1)
            return null;
        byte[] encrypted = new byte[src.length() / 2];
        for (int i = 0; i < src.length() / 2; i++) {
            int high = Integer.parseInt(src.substring(i * 2, i * 2 + 1), 16);
            int low = Integer.parseInt(src.substring(i * 2 + 1, i * 2 + 2), 16);

            encrypted[i] = (byte) (high * 16 + low);
        }
        return encrypted;
    }

    public static void main(String args[]) {
        String str = AESEncrypter.getInstance().encrypt("192.168.30.193.123");
        System.out.println(str);
        System.out.println(AESEncrypter.getInstance().decrypt(str));
    }
}