RSA对文件加解密

纯手打代码，借鉴了下面网址中的已有的函数，已完整实现

package RSA;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.OutputStream;
import java.nio.file.Files;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.SecureRandom;
import java.util.List;

import javax.crypto.Cipher;

import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.omg.CORBA.portable.InputStream;
import java.io.File;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;
import java.io.*;

public class RSAFile2 {
	//生成秘钥对，放到xml文件中
	public static  void saveRSAKey() {
		try {
			SecureRandom sr = new SecureRandom();
			KeyPairGenerator kg = KeyPairGenerator.getInstance("RSA", new org.bouncycastle.jce.provider.BouncyCastleProvider());
			kg.initialize(1024,sr);
			FileOutputStream fos = new FileOutputStream("C:/RSAKey.xml");
			ObjectOutputStream oos = new ObjectOutputStream(fos);
			//生成秘钥
			oos.writeObject(kg.generateKeyPair());
			oos.close();
		} catch(Exception e) {
			e.printStackTrace();
		}
	}
	

	//获取加密秘钥
	public static KeyPair getKeyPair() throws Exception {
		KeyPair kp;
		try {
			String fileName="C:/RSAKey.xml";
			//InputStream is = FileUtils.class.getClassLoader().getResourceAsStream(fileName);
			FileInputStream is = new FileInputStream(fileName);
			ObjectInputStream oos = new ObjectInputStream(is);
			kp = (KeyPair)oos.readObject();
			oos.close();
		} catch(Exception e) {
			throw new Exception("读取加密文件出错.",e);
		}
		return kp;
	}
	
	//加密文件
	public static void encryptFile(String srcFileName,String destFileName)throws Exception {
		OutputStream outputWriter = null;
		FileInputStream inputReader = null;
		try {
			Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding",new org.bouncycastle.jce.provider.BouncyCastleProvider());
			byte[] buf = new byte[100];
			int buf1;
			cipher.init(Cipher.ENCRYPT_MODE, getKeyPair().getPublic());
			outputWriter = new FileOutputStream(destFileName);
			inputReader = new FileInputStream(srcFileName);
			while((buf1 = inputReader.read(buf))!=-1) {
				byte[] encText = null;
				byte[] newArr = null;
				if(buf.length == buf1) {
					newArr = buf;
				}else {
					newArr = new byte[buf1];
					for(int i = 0;i < buf1;i++) {
						newArr[i]=(byte)buf[i];
					}
				}
				encText = cipher.doFinal(newArr);
				outputWriter.write(encText);
			}
			outputWriter.flush();
		}catch (Exception e) {
			throw e;
		}finally {
			try {
				if(outputWriter != null) {
					outputWriter.close();
				}
			}catch (Exception e) {
				throw e;
		}
	}
 }
	
	//解密
	public static void decryptFile(String srcFileName,String destFileName) throws Exception {
		OutputStream outputWriter = null;
		FileInputStream inputReader =null;
		try {
			Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding",new org.bouncycastle.jce.provider.BouncyCastleProvider());
			byte[] buf = new byte[128];
			int buf1;
			cipher.init(Cipher.DECRYPT_MODE, getKeyPair().getPrivate());
			outputWriter = new FileOutputStream(destFileName);
			inputReader = new FileInputStream(srcFileName);
			while((buf1 = inputReader.read(buf))!=-1){
				byte[] encText = null;
				byte[] newArr = null;
				if(buf.length == buf1) {
					newArr = buf;
				} else {
					newArr = new byte[buf1];
					for(int i=0;i