java 加密

1.Base64 加密

import sun.misc.BASE64Decoder;import sun.misc.BASE64Encoder;import java.security.MessageDigest;public class Coder {public static void main(String[] args) {try {//1. base64 加密、解密System.out.println("=========1. base64 加密、解密=========");String name_for_base64 = "123456";System.out.println("加密之前：" + name_for_base64);String encrypt_name_for_base64 = encryptBASE64(name_for_base64.getBytes());System.out.println("加密之后：" + encrypt_name_for_base64);byte[] decrypt_name_for_base64 = decryptBASE64(encrypt_name_for_base64);System.out.println("解密之后：" + new String(decrypt_name_for_base64));//2. md5 加密System.out.println("=========2. md5 加密=========");String name_for_md5= "123456";System.out.println("加密之前：" + name_for_md5);byte[] encrypt_name_for_md5 =encryptMD5(name_for_md5.getBytes());System.out.println("加密之后：" + new String(encrypt_name_for_md5));//3. sha 加密System.out.println("=========2. sha 加密=========");String name_for_sha= "123456";System.out.println("加密之前：" + name_for_sha);byte[] encrypt_name_for_sha =encryptSHA(name_for_sha.getBytes());System.out.println("加密之后：" + new String(encrypt_name_for_sha));} catch (Exception e) {e.printStackTrace();}}public static final String KEY_SHA = "SHA";public static final String KEY_MD5 = "MD5";/** * BASE64解密 *  * @param key * @return * @throws Exception */public static byte[] decryptBASE64(String key) throws Exception {return (new BASE64Decoder()).decodeBuffer(key);}/** * BASE64加密 *  * @param key * @return * @throws Exception */public static String encryptBASE64(byte[] key) throws Exception {return (new BASE64Encoder()).encodeBuffer(key);}/** * MD5加密 *  * @param data * @return * @throws Exception */public static byte[] encryptMD5(byte[] data) throws Exception {MessageDigest md5 = MessageDigest.getInstance(KEY_MD5);md5.update(data);return md5.digest();}/** * SHA加密 *  * @param data * @return * @throws Exception */public static byte[] encryptSHA(byte[] data) throws Exception {MessageDigest sha = MessageDigest.getInstance(KEY_SHA);sha.update(data);return sha.digest();}}

2.SHA 加密

import java.security.Key;import java.security.KeyFactory;import java.security.KeyPair;import java.security.KeyPairGenerator;import java.security.interfaces.RSAPrivateKey;import java.security.interfaces.RSAPublicKey;import java.security.spec.PKCS8EncodedKeySpec;import java.security.spec.X509EncodedKeySpec;import java.util.Arrays;import java.util.HashMap;import java.util.Map;import javax.crypto.Cipher;/** * 这个加密用到了上面 base64 的加密类 * @author Administrator * */public class RSAEncrypter {public static void main(String[] args) throws Exception {String name = "123abc";// 初始化之后的公钥、私钥System.out.println("公钥：" + getPublicKey(keyMap));System.out.println("私钥：" +getPrivateKey(keyMap));// 使用 rsa 公钥加密，私钥解密System.out.println("使用 公钥->加密、私钥->解密");System.out.println("加密之前数据：" + name);byte[] encrypt_by_pubkey = encryptByPublicKey(name.getBytes(), getPublicKey(keyMap));System.out.println("公钥加密之后 byte[] : " + Arrays.toString(encrypt_by_pubkey));byte[] decrypt_by_prikey = decryptByPrivateKey(encrypt_by_pubkey, getPrivateKey(keyMap));System.out.println("私钥解密之后 byte[] : " + Arrays.toString(decrypt_by_prikey));System.out.println("解密之后数据：" + new String(decrypt_by_prikey));System.out.println("==============================");// 使用 rsa 私钥加密，公钥解密System.out.println("使用 私钥->加密，公钥->解密");System.out.println("加密之前数据：" + name);byte[] encrypt_by_prikey = encryptByPrivateKey(name.getBytes(), getPrivateKey(keyMap));System.out.println("私钥加密之后 byte[] : " + Arrays.toString(encrypt_by_prikey));byte[] decrypt_by_pubkey = decryptByPublicKey(encrypt_by_prikey, getPublicKey(keyMap));System.out.println("私钥解密之后 byte[] : " + Arrays.toString(decrypt_by_pubkey));System.out.println("解密之后数据：" + new String(decrypt_by_pubkey));}  /** * 加密的方式 */public static final String KEY_ALGORTHM="RSA";//  public static final String SIGNATURE_ALGORITHM="MD5withRSA";     /** * 公钥 */public static final String PUBLIC_KEY = "RSAPublicKey";//公钥  /** * 私钥 */public static final String PRIVATE_KEY = "RSAPrivateKey";//私钥private static Map<String,Object> keyMap = initKey();    /**     * 初始化密钥     * @return     * @throws Exception     */    public static Map<String,Object> initKey() {    Map<String,Object> keyMap = new HashMap<String, Object>(2);    try {        KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance(KEY_ALGORTHM);        keyPairGenerator.initialize(1024);//        keyPairGenerator.initialize(512);        KeyPair keyPair = keyPairGenerator.generateKeyPair();                 //公钥        RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();        //私钥        RSAPrivateKey privateKey =  (RSAPrivateKey) keyPair.getPrivate();                 keyMap.put(PUBLIC_KEY, publicKey);        keyMap.put(PRIVATE_KEY, privateKey);    } catch (Exception  e) {    e.printStackTrace();    }        return keyMap;    }      /**     * 取得公钥，并转化为String类型     * @param keyMap     * @return     * @throws Exception     */    public static String getPublicKey(Map<String, Object> keyMap)throws Exception{        Key key = (Key) keyMap.get(PUBLIC_KEY);          return Coder.encryptBASE64(key.getEncoded());         }     /**     * 取得私钥，并转化为String类型     * @param keyMap     * @return     * @throws Exception     */    public static String getPrivateKey(Map<String, Object> keyMap) throws Exception{        Key key = (Key) keyMap.get(PRIVATE_KEY);          return Coder.encryptBASE64(key.getEncoded());         }            /**     * 用私钥加密     * @param data  加密数据     * @param key   密钥     * @return     * @throws Exception     */    public static byte[] encryptByPrivateKey(byte[] data,String key)throws Exception{        //解密密钥        byte[] keyBytes = Coder.decryptBASE64(key);        //取私钥        PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(keyBytes);        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORTHM);        Key privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);                 //对数据加密        Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());        cipher.init(Cipher.ENCRYPT_MODE, privateKey);                 return cipher.doFinal(data);    }        /**     * 用私钥解密<span style="color:#000000;"></span> * @param data  加密数据     * @param key   密钥     * @return     * @throws Exception     */    public static byte[] decryptByPrivateKey(byte[] data,String key)throws Exception{        //对私钥解密        byte[] keyBytes = Coder.decryptBASE64(key);                 PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(keyBytes);        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORTHM);        Key privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);        //对数据解密        Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());        cipher.init(Cipher.DECRYPT_MODE, privateKey);                 return cipher.doFinal(data);    }        /**     * 用公钥加密     * @param data  加密数据     * @param key   密钥     * @return     * @throws Exception     */    public static byte[] encryptByPublicKey(byte[] data,String key)throws Exception{        //对公钥解密        byte[] keyBytes = Coder.decryptBASE64(key);        //取公钥        X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(keyBytes);        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORTHM);        Key publicKey = keyFactory.generatePublic(x509EncodedKeySpec);                 //对数据解密        Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());        cipher.init(Cipher.ENCRYPT_MODE, publicKey);                 return cipher.doFinal(data);    }        /**     * 用公钥解密     * @param data  加密数据     * @param key   密钥     * @return     * @throws Exception     */    public static byte[] decryptByPublicKey(byte[] data,String key)throws Exception{        //对私钥解密        byte[] keyBytes = Coder.decryptBASE64(key);        X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(keyBytes);        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORTHM);        Key publicKey = keyFactory.generatePublic(x509EncodedKeySpec);                 //对数据解密        Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());        cipher.init(Cipher.DECRYPT_MODE, publicKey);                 return cipher.doFinal(data);    }}