DES加密-java版

import java.security.Key;
import java.security.Security;

import javax.crypto.Cipher;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

public class DES {
  
Key key;

public DES(String str) {
    setKey(str);//生成密匙
}

public DES() {
    setKey("computer_123");
}


/**
   * 根据参数生成KEY
   */
public void setKey(String strKey) {
      try { 
    	  Security.addProvider(new com.sun.crypto.provider.SunJCE());
    	  this.key = getKey(strKey.getBytes());
      } catch (Exception e) {
        throw new RuntimeException(
            "Error initializing SqlMap class. Cause: " + e);
      }
}

	private Key getKey(byte[] arrBTmp) throws Exception {
		// 创建一个空的8位字节数组（默认值为0）
		byte[] arrB = new byte[8];

		// 将原始字节数组转换为8位
		for (int i = 0; i < arrBTmp.length && i < arrB.length; i++) {
			arrB[i] = arrBTmp[i];
		}

		// 生成密钥
		Key key = new javax.crypto.spec.SecretKeySpec(arrB, "DES");

		return key;
	}


/**
   * 加密String明文输入,String密文输出
   */
public String getEncString(String strMing) {
      byte[] byteMi = null;
      byte[] byteMing = null;
      String strMi = "";
      BASE64Encoder base64en = new BASE64Encoder();
      try {
        byteMing = strMing.getBytes("UTF8");
        byteMi = this.getEncCode(byteMing);
        strMi = base64en.encode(byteMi);
      } catch (Exception e) {
        throw new RuntimeException(
            "Error initializing SqlMap class. Cause: " + e);
      } finally {
        base64en = null;
        byteMing = null;
        byteMi = null;
      }
      return strMi;
}

/**
   * 解密 以String密文输入,String明文输出
   * @param strMi
   * @return
   */
public String getDesString(String strMi) {
      BASE64Decoder base64De = new BASE64Decoder();
      byte[] byteMing = null;
      byte[] byteMi = null;
      String strMing = "";
      try {
        byteMi = base64De.decodeBuffer(strMi);
        byteMing = this.getDesCode(byteMi);
        strMing = new String(byteMing, "UTF8");
      } catch (Exception e) {
        throw new RuntimeException(
            "Error initializing SqlMap class. Cause: " + e);
      } finally {
        base64De = null;
        byteMing = null;
        byteMi = null;
      }
      return strMing;
}

/**
   * 加密以byte[]明文输入,byte[]密文输出
   * @param byteS
   * @return
   */
private byte[] getEncCode(byte[] byteS) {
      byte[] byteFina = null;
      Cipher cipher;
      try {
        cipher = Cipher.getInstance("DES");
        cipher.init(Cipher.ENCRYPT_MODE, key);
        byteFina = cipher.doFinal(byteS);
      } catch (Exception e) {
        throw new RuntimeException(
            "Error initializing SqlMap class. Cause: " + e);
      } finally {
        cipher = null;
      }
      return byteFina;
}

/**
   * 解密以byte[]密文输入,以byte[]明文输出
   * @param byteD
   * @return
   */
private byte[] getDesCode(byte[] byteD) {
      Cipher cipher;
      byte[] byteFina = null;
      try {
        cipher = Cipher.getInstance("DES");
        cipher.init(Cipher.DECRYPT_MODE, key);
        byteFina = cipher.doFinal(byteD);
      } catch (Exception e) {
        throw new RuntimeException(
            "Error initializing SqlMap class. Cause: " + e);
      } finally {
        cipher = null;
      }
      return byteFina;
}

public static void main(String args[]) {
      DES des = new DES("tom");
      // 设置密钥
      //des.setKey("12345678");

      String str1 = "www.baidu";
      //DES加密
      String str2 = des.getEncString(str1);
     
      String deStr = des.getDesString(str2);
      System.out.println("密文:" + str2);
      //DES解密
      System.out.println("明文:" + deStr);
}

}