Java 如何提高加密程序的速度?
您好首先介绍一下该程序的功能 A:它需要密码 B:它为用户密码的每个字符创建一个arraylist C:它将创建的数组列表存储在Arraylist中(Arraylist>) 程序逐字读入一本书。加密字符(使用ADFGVX polybius平方密码)并将加密字符添加到ArrayList 如果密码为lid,则第一个字符进入列表1,第二个字符进入列表2,第三个字符进入列表3,第四个字符再次进入列表1。直到所有字符都读入 E:它按照第一个字符的字母顺序对列表进行排序。 所以密码[l,i,d]将被排序为[d,i,l] F:然后程序将字符解密回其原始形式,并将它们添加到一个数组列表中,然后打印到文件中 孔代码如下所示。我读取的文件大小为3120KB,包含大约320万个字符。 在我的机器上,hole程序将在0.7秒内完成所有操作 有没有办法让它跑得更快? 我的一个想法是使用linkedhashmap来存储ArrayList,而不是使用ArrayList> 我从未使用过链接的hashmap,也不知道如何按字母顺序对列表进行排序 任何能帮助我加快项目进度的想法或建议都将不胜感激。 (我正在运行java 1.8)Java 如何提高加密程序的速度?,java,performance,encryption,arraylist,hashmap,Java,Performance,Encryption,Arraylist,Hashmap,您好首先介绍一下该程序的功能 A:它需要密码 B:它为用户密码的每个字符创建一个arraylist C:它将创建的数组列表存储在Arraylist中(Arraylist>) 程序逐字读入一本书。加密字符(使用ADFGVX polybius平方密码)并将加密字符添加到ArrayList 如果密码为lid,则第一个字符进入列表1,第二个字符进入列表2,第三个字符进入列表3,第四个字符再次进入列表1。直到所有字符都读入 E:它按照第一个字符的字母顺序对列表进行排序。 所以密码[l,i,d]将被排序为[
包gmit;
导入java.util.*;
导入java.io.*;
导入java.nio.charset.charset;
公共类项目{
//创建Hashmap
私有静态HashMap stringmap=新HashMap();
//创建字符串数组列表
私有静态ArrayList mylist=新ArrayList();
私有静态ArrayList lol=新ArrayList();
//声明整型变量
私有静态int encryptioncounter=0,decryptioncounter=0,lastindexcounter=0,mylistindexcounter=0;
//声明字符串变量
私有静态字符串密码,值;
私有静态字符串结果;
//第三十四天——主要开始--------------------------------------------------------
公共静态void main(字符串[]args)引发IOException{
//方法来填充HashMap
puttuffinstrinmap();
System.out.println(“请输入您的密码”);
//获取用户输入
扫描仪输入=新扫描仪(系统输入);
password=in.nextLine();
//循环启动
//按密码的字符数创建数组列表
//将创建的Arraylist添加到Arraylist mylist。
对于(int i=0;il1.get(0).compareTo(l2.get(0));
//调用解密方法
解密();
writetofile();
//结束计时器
long-endTime=System.nanoTime();
长总时间=结束时间-开始时间;
//打印时间
双秒=(双)总时间/100000000.0;
系统输出打印项次(秒+总时间);
}
//---------------------------------------端干管-----------------------------------------
私有静态void writetofile()引发FileNotFoundException,UnsupportedEncodingException{
PrintWriter=新的PrintWriter(“finished.txt”、“UTF-8”);
StringBuilder=新的StringBuilder();
for(字符串值:lol){
附加(值);
}
字符串s=builder.toString();
//字符串s=lol.toString();
作者:println(s);
writer.close();
}
//-------------------------------------加密开始-------------------------------------
私有静态void加密(字符串){
//得到
value=stringmap.get(字符串);
mylist.get(encryptioncounter).add(value);
//将一个添加到计数器
encryptioncounter++;
如果(encryptioncounter>=password.length()){
encryptioncounter=0;
//将一个添加到计数器
lastindexcounter++;
}
}
//-------------------------------------加密结束---------------------------------------
//-------------------------------------解密开始-------------------------------------
私有静态void decrypt(){
int这个计数器=0;
while(decryptioncounter!=此计数器){
for(int i=0;i=lastindexcounter){
解密计数器=此计数器;
}
}
mylistindexcounter++;
}
}
//------------------------------------解密结束---------------------------------------
//-------------------------------------地图人口开始---------------------------------
公共sta
package gmit;
import java.util.*;
import java.io.*;
import java.nio.charset.Charset;
public class project {
// Creating Hashmap
private static HashMap<String, String> stringmap = new HashMap<String, String>();
// Creating String Array lists
private static ArrayList<ArrayList<String>> mylist = new ArrayList<ArrayList<String>>();
private static ArrayList<String> lol = new ArrayList<String>();
// Declaring int variables
private static int encryptioncounter=0,decryptioncounter=0,lastindexcounter=0,mylistindexcounter=0;
// Declaring String variables
private static String password,value;
private static String result;
// ----------------------------------------------- Main start --------------------------------------------------------
public static void main(String[] args) throws IOException {
// Method to populate HashMap
putstuffinstrinmap();
System.out.println("Pleaseinput your passphrase");
// Gets user Input
Scanner in = new Scanner(System.in);
password = in.nextLine();
// Starts for loop
// Creates Array list in number of the amount of characters of the password
// Adds created arraylists to Arraylist<List> mylist.
for (int i = 0; i < password.length(); i++) {
List<String> firstCharandMore= new ArrayList<>();
char c = password.charAt(i);
firstCharandMore.add(String.valueOf(c));
mylist.add((ArrayList<String>) firstCharandMore);
}
//Starts Timer
long startTime = System.currentTimeMillis();
// Reads in File in UTF-8 format
// gets back a character
BufferedReader reader = new BufferedReader(
new InputStreamReader(
new FileInputStream("WarAndPeace-LeoTolstoy.txt"),
Charset.forName("UTF-8")));
int c;
while((c = reader.read()) != -1) {
char string = (char) c;
// Converts Character to upper case String
// Passes the string into encryption method
encrypt(Character.toString(string).toUpperCase());
// Adds one to counter
decryptioncounter++;
}
// Creates new Arraylist listToSort (Copy of mylist)
// Sorts Array lists in alphabetic order by first character from each list
List<List<String>> listToSort = new ArrayList<>(mylist);
listToSort.sort((l1, l2) -> l1.get(0).compareTo(l2.get(0)));
// Calls decryption method
decrypt();
writetofile();
// Ends Timer
long endTime = System.nanoTime();
long totalTime = endTime - startTime;
// Prints Time
double seconds = (double)totalTime / 1000000000.0;
System.out.println(seconds+" Total time");
}
// ------------------------------------ End Main -----------------------------------------
private static void writetofile() throws FileNotFoundException, UnsupportedEncodingException {
PrintWriter writer = new PrintWriter("finished.txt", "UTF-8");
StringBuilder builder = new StringBuilder();
for (String value : lol) {
builder.append(value);
}
String s = builder.toString();
//String s = lol.toString();
writer.println(s);
writer.close();
}
// -------------------------------- Encryption Start -------------------------------------
private static void encrypt(String string) {
// Gets
value= stringmap.get(string);
mylist.get(encryptioncounter).add(value);
// Adds one to counter
encryptioncounter++;
if(encryptioncounter>=password.length()){
encryptioncounter=0;
// Adds one to counter
lastindexcounter++;
}
}
// --------------------------------- Encryption End ---------------------------------------
// --------------------------------- Decryption Start -------------------------------------
private static void decrypt() {
int thiscounter=0;
while(decryptioncounter != thiscounter ){
for(int i=0;i <password.length() ;i++){
String ba = mylist.get(i).get(mylistindexcounter);
result= stringmap.get(ba);
lol.add(result);
thiscounter++;
if(mylistindexcounter >=lastindexcounter){
decryptioncounter =thiscounter;
}
}
mylistindexcounter++;
}
}
// ---------------------------------- Decryption End ---------------------------------------
// --------------------------------- Map population start ---------------------------------
public static void putstuffinstrinmap(){
stringmap.put("AA", "P");//AA - P
stringmap.put("AD", "H");//AD - H
stringmap.put("AF", "0");//
stringmap.put("AG", "Q");//
stringmap.put("AV", "G");//
stringmap.put("AX", "6");//
stringmap.put("DA", "4");//
stringmap.put("DD", "M");//
stringmap.put("DF", "E");//
stringmap.put("DG", "A");//
stringmap.put("DV", "1");//
stringmap.put("DX", "Y");//
stringmap.put("FA", "L");//
stringmap.put("FD", "2");//
stringmap.put("FF", "N");//
stringmap.put("FG", "O");//
stringmap.put("FV", "F");//
stringmap.put("FX", "D");//
stringmap.put("GA", "X");//
stringmap.put("GD", "K");//
stringmap.put("GF", "R");//
stringmap.put("GG", "3");//
stringmap.put("GV", "C");//
stringmap.put("GX", "V");//
stringmap.put("VA", "S");//
stringmap.put("VD", "5");//
stringmap.put("VF", "Z");//
stringmap.put("VG", "W");//
stringmap.put("VV", "7");//
stringmap.put("VX", "B");//
stringmap.put("XA", "J");//
stringmap.put("XD", "9");//
stringmap.put("XF", "U");//
stringmap.put("XG", "T");//
stringmap.put("XV", "I");//
stringmap.put("XX", "8");//
stringmap.put("P", "AA");//
stringmap.put("H", "AD");//
stringmap.put("0", "AF");//
stringmap.put("Q", "AG");//
stringmap.put("G", "AV");//
stringmap.put("6", "AX");//
stringmap.put("4", "DA");//
stringmap.put("M", "DD");//
stringmap.put("E", "DF");//
stringmap.put("A", "DG");//
stringmap.put("1", "DV");//
stringmap.put("Y", "DX");//
stringmap.put("L", "FA");//
stringmap.put("2", "FD");//
stringmap.put("N", "FF");//
stringmap.put("O", "FG");//
stringmap.put("F", "FV");//
stringmap.put("D", "FX");//
stringmap.put("X", "GA");//
stringmap.put("K", "GD");//
stringmap.put("R", "GF");//
stringmap.put("3", "GG");//
stringmap.put("C", "GV");//
stringmap.put("V", "GX");//
stringmap.put("S", "VA");//
stringmap.put("5", "VD");//
stringmap.put("Z", "VF");//
stringmap.put("W", "VG");//
stringmap.put("7", "VV");//
stringmap.put("B", "VX");//
stringmap.put("J", "XA");//
stringmap.put("9", "XD");//
stringmap.put("U", "XF");//
stringmap.put("T", "XG");//
stringmap.put("I", "XV");//
stringmap.put("8", "XX");//
stringmap.put("AH", ".");//
stringmap.put("DH", "!");//
stringmap.put("FH", "?");//
stringmap.put("GH", " ");//
stringmap.put("VH", "'");//
stringmap.put("XH", ",");//
stringmap.put(".", "AH");//
stringmap.put("!", "DH");//
stringmap.put("?", "FH");//
stringmap.put(" ", "GH");//
stringmap.put("'", "VH");//
stringmap.put(",", "XH");//
stringmap.put("AP", "]");//
stringmap.put("DP", "[");//
stringmap.put("FP", "~");//
stringmap.put("GP", "&");//
stringmap.put("VP", ":");//
stringmap.put("XP", ";");//
stringmap.put("AP", "-");//"
stringmap.put("DP", "");//
stringmap.put("FP", "*");//
stringmap.put("GP", "^");//
stringmap.put("VP", "\"");//
stringmap.put(null, " ");//
}
// --------------------------------- Map population End -----------------------------------
}