Question

我的代码存在问题。我有一个println语句，在netbeans中打印一个字符串到输出部分（控制台）。但是当我在命令提示符下编译并运行它时，程序不会打印输出。我将System.out.println(plaintext)替换为System.out.println("Hello world")并且它有效。代码如下。

netbeans输出：

gjfjdjddkslskaskdkmfaoadfadvg

和控制台：

Microsoft Windows [Version 10.0.14393]
(c) 2016 Microsoft Corporation. All rights reserved.

C:\Users\KJ4CC>cd C:\Users\KJ4CC\OneDrive\Documents\NetBeansProjects\cipher\src\cipher

C:\Users\KJ4CC\OneDrive\Documents\NetBeansProjects\cipher\src\cipher>javac Cipher.java

C:\Users\KJ4CC\OneDrive\Documents\NetBeansProjects\cipher\src\cipher>cd ..

C:\Users\KJ4CC\OneDrive\Documents\NetBeansProjects\cipher\src>java cipher.Cipher

C:\Users\KJ4CC\OneDrive\Documents\NetBeansProjects\cipher>

这是代码：

package cipher;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Scanner;

/**
 *
 * @author KJ4CC
 */
public class Cipher {

    char[] text;

    public static void main(String[] args) {
        String plainText;
        String cipherText;

        Cipher cipher = new Cipher();
//these arnt used as of right now. will pass this to the encrypt method, for the text to be encrypted.
        String original = "";
        String iv = "fsf";
        String key = "hel";

        //calls read file, that will put the text that needs to be encrypted into a char array. 
        plainText = cipher.readFile(iv);
        cipherText = cipher.encrypt(original, iv, key);
        System.out.printf(plainText);
        cipher.output(plainText,cipherText,iv,key);
    }

    public String encrypt(String orig, String iv, String key) {
        int i, j, result;
        String cipherText = "";
        int b = iv.length();
        //loops through the entire set of chars 
        /*for (i = 0; i < text.length; i += b) {
            //Splits the char into block the size of the IV block. 
            for (j = 0; j < b; j++) {
                if(i == 0){
                result = ((iv.charAt(j) - 'a') + (text[j + i] - 'a'))%26;

                }else{
                result = ((key.charAt(j) - 'a') + (text[j + i] - 'a'))%26;


                        }

            }
           // System.out.println(", ");
        }
*/
        return cipherText;

    }

    public String readFile(String iv) {
        String plainText = "";
        try {
            //opens file and reads all of the text into a string.
            String fileString = new Scanner(new File("text.txt"))
                    .useDelimiter("\\A+").next();
            //removes all of the spaces and special chars, to be put into the char array 
            fileString = fileString.replaceAll(" ", "");
            fileString = fileString.replaceAll("[',',':','.',' ','(', ' )', '--','/','\\s']", "");

            //puts the editied string back into a char array for storage.
            //adding letters too bufer the iv
            int bufferLetters = fileString.length();
            bufferLetters = fileString.length() % iv.length();
            if (bufferLetters > 0) {
                bufferLetters = iv.length() - bufferLetters;

                for (int i = 0; i < bufferLetters; i++) {
                    fileString = fileString + "x";
                }
            }
            fileString = fileString.toLowerCase();
            plainText = fileString;
            text = fileString.toCharArray();

        } catch (IOException e) {

        }
        return plainText;
    }
    public void output(String plainText, String cipherText, String iv, String key){

    }
}

java版：

java version "1.8.0_101"
Java(TM) SE Runtime Environment (build 1.8.0_101-b13)
Java HotSpot(TM) 64-Bit Server VM (build 25.101-b13, mixed mode)

Answer 1

text.txt可能位于NetBeans的文件路径上，但是当您从命令提示符编译/执行javac / java时则不行。在后一种情况下，您会收到IOException，因为找不到该文件，但catch块为空。尝试将一个System.out.println（）添加到catch块中，并在使用独立的javac / java编译/执行时打印该消息

程序不会打印到命令提示符，但会打印到netbeans控制台

1 个答案: