问题描述:
各位好,请求各位java学习者帮助钉解决这个问题。
我想用des算法对我的名字进行加密
我也在网上下载了des算法,包括FileDES,SubKey,Des各程序,
可能没真正理解这些程序,所以我想调用都不知道将这些东西
组合起来,有知道的请帮帮忙啊!
解析:
package des
import java.io.*
import java.nio.*
import java.nio.channels.FileChannel
public class FileDES{
private static final boolean enc=true加密
private static final boolean dec=false解密
private String srcFileName
private String destFileName
private String inKey
private boolean actionType
private File srcFile
private File destFile
private Des des
private void *** yzePath(){
String dirName
int pos=srcFileNamestIndexOf("/")
dirName=srcFileName.substring(0,pos)
File dir=new File(dirName)
if (!dir.exists()){
System.err.println(dirName+" is not exist")
System.exit(1)
}else if(!dir.isDirectory()){
System.err.println(dirName+" is not a directory")
System.exit(1)
}
pos=destFileNamestIndexOf("/")
dirName=destFileName.substring(0,pos)
dir=new File(dirName)
if (!dir.exists()){
if(!dir.mkdirs()){
System.out.println ("can not creat directory:"+dirName)
System.exit(1)
}
}else if(!dir.isDirectory()){
System.err.println(dirName+" is not a directory")
System.exit(1)
}
}
private static int replenish(FileChannel channel,ByteBuffer buf) throws IOException{
long byteLeft=channel.size()-channel.position()
if(byteLeft==0L)
return -1
buf.position(0)
buf.limit(buf.position()+(byteLeft<8 ? (int)byteLeft :8))
return channel.read(buf)
}
private void file_operate(boolean flag){
des=new Des(inKey)
FileOutputStream outputFile=null
try {
outputFile=new FileOutputStream(srcFile,true)
}catch (java.io.FileNotFoundException e) {
e.printStackTrace(System.err)
}
FileChannel outChannel=outputFile.getChannel()
try{
if(outChannel.size()%2!=0){
ByteBuffer bufTemp=ByteBuffer.allocate(1)
bufTemp.put((byte)32)
bufTemp.flip()
outChannel.position(outChannel.size())
outChannel.write(bufTemp)
bufTemp.clear()
}
}catch(Exception ex){
ex.printStackTrace(System.err)
System.exit(1)
}
FileInputStream inFile=null
try{
inFile=new FileInputStream(srcFile)
}catch(java.io.FileNotFoundException e){
e.printStackTrace(System.err)
System.exit(1)
}
outputFile=null
try {
outputFile=new FileOutputStream(destFile,true)
}catch (java.io.FileNotFoundException e) {
e.printStackTrace(System.err)
}
FileChannel inChannel=inFile.getChannel()
outChannel=outputFile.getChannel()
ByteBuffer inBuf=ByteBuffer.allocate(8)
ByteBuffer outBuf=ByteBuffer.allocate(8)
try{
String srcStr
String destStr
while(true){
if (replenish(inChannel,inBuf)==-1) break
srcStr=((ByteBuffer)(inBuf.flip())).asCharBuffer().toString()
inBuf.clear()
if (flag)
destStr=des.enc(srcStr,srcStr.length())
else
destStr=des.dec(srcStr,srcStr.length())
outBuf.clear()
if (destStr.length()==4){
for (int i = 0i<4i++) {
outBuf.putChar(destStr.charAt(i))
}
outBuf.flip()
}else{
outBuf.position(0)
outBuf.limit(2*destStr.length())
for (int i = 0i<destStr.length()i++) {
outBuf.putChar(destStr.charAt(i))
}
outBuf.flip()
}
try {
outChannel.write(outBuf)
outBuf.clear()
}catch (java.io.IOException ex) {
ex.printStackTrace(System.err)
}
}
System.out.println (inChannel.size())
System.out.println (outChannel.size())
System.out.println ("EoF reached.")
inFile.close()
outputFile.close()
}catch(java.io.IOException e){
e.printStackTrace(System.err)
System.exit(1)
}
}
public FileDES(String srcFileName,String destFileName,String inKey,boolean actionType){
this.srcFileName=srcFileName
this.destFileName=destFileName
this.actionType=actionType
*** yzePath()
srcFile=new File(srcFileName)
destFile=new File(destFileName)
this.inKey=inKey
if (actionType==enc)
file_operate(enc)
else
file_operate(dec)
}
public static void main(String[] args){
String file1=System.getProperty("user.dir")+"/111.doc"
String file2=System.getProperty("user.dir")+"/222.doc"
String file3=System.getProperty("user.dir")+"/333.doc"
String passWord="1234ABCD"
FileDES fileDes=new FileDES(file1,file2,passWord,true)
FileDES fileDes1=new FileDES(file2,file3,passWord,false)
}
1.密钥不同2.程序算法不同:不是说DES的算法,是指你所写的程序代码去实现DES算法不同,象有些关于循环部分的代码,不同的人可能写的不同,导致程序代码在大量加密时效率不高
暂时只想到这了...
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