encryptclasses.java

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import java.security.SecureRandom;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
import javax.crypto.Cipher;

public class EncryptClasses {
	static public void main(String args[]) throws Exception {		
		//读取密钥
		DealFile df = new DealFile();
		df.connFIS(args[0]);
		byte rawKeyData[] = df.readByte();
		df.closeFIS();
		
		//读取加密的类
		df.connFIS(args[1]);
		byte data[] = df.readByte();
		df.closeFIS();

		//DES算法要求有一个可信任的随机数源 
		SecureRandom sr = new SecureRandom(); 

		//从原始密匙数据创建DESKeySpec对象 
		DESKeySpec dks = new DESKeySpec( rawKeyData ); 

		//创建一个密匙工厂，然后用它把DESKeySpec转换成一个SecretKey对象 
		SecretKeyFactory keyFactory = SecretKeyFactory.getInstance( "DES" ); 
		SecretKey key = keyFactory.generateSecret( dks ); 

		//Cipher对象实际完成加密操作 
		Cipher cipher = Cipher.getInstance( "DES" ); 

		//用密匙初始化Cipher对象 
		cipher.init( Cipher.ENCRYPT_MODE, key, sr ); 

		//正式执行加密操作 
		byte encryptedData[] = cipher.doFinal( data ); 
		
		//重写加密后的类
		df.connFOS(args[1]);
		df.writeByte(encryptedData);
		df.closeFOS();
	}
}