必须输入输入两次扫描仪才能读取它

时间:2013-03-31 00:09:32

标签: java string methods input

所以在这段代码中,在" Run"在方法" run"中,扫描仪似乎不想从第一次尝试中获取输入,只在第二行输入输入。我说第二行是因为我输入了输入然后按两次返回,然后在第三行输入输入,它读取第二行,在这种情况下就没有了。

我尝试过BufferedReader的结果相同,所以我相信我正在做一些愚蠢的事情而忽视了一些事情。

import java.util.Scanner;
import java.util.ArrayList;
import java.util.Timer;
import java.util.TimerTask;

import java.io.*;

class Global {
    public static int stop = -1;
}

public class DataSort {

    public static void main(String[] args){

        Timer timer = new Timer();
        Direct swit = new Direct();
        Run mprog = new Run();
        Help hlp = new Help();

        String newline = System.getProperty("line.separator");

        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        Scanner console = new Scanner(System.in);

        System.out.println(newline);
        System.out.println("Welcome to Data Sort! This Program is designed to sort information about targets discoverd by UAV and place the data in a table." + newline);
        System.out.print("For help, press any key. To continue, please wait. ");
        timer.schedule(swit, 3000);

        try {
            Global.stop = in.read();
        } 

        catch(IOException e) {
            e.printStackTrace();
        }

        try {
            in.close();
        }

        catch(IOException e) {
            e.printStackTrace();
        }
    }
}

class Direct extends TimerTask {

    public void run() {

        Run mprog = new Run();
        Help hlp = new Help();

        if(Global.stop != -1){
            System.out.println("Help");
            hlp.run();
        }

        if(Global.stop == -1) {
            System.out.println("Main");
            mprog.run();
        }
    }
}


class Help {

    public static void run() {
        String newline = System.getProperty("line.separator");

        System.out.print(newline);
        System.out.println("Entering Help Mode!" + newline);

        System.out.println("Entered Help Class");
        //String help = console.nextLine();
    }
}

class Run {

    public static void run() {

        /*EnterAll eall = new EnterAll();
        EnterCoords ecoords = new EnterCoords();
        EnterRelation erelat = new EnterRelation();
        EnterColor ecolor = new EnterColor();
        EnterShape eshape = new EnterShape();
        Coordinates coords = new Coordinates();
        Relation relat = new Relation();
        Color color = new Color();
        Shape shape = new Shape();
        List list = new List();
        Save save = new Save();
        SaveAs saveas = new SaveAs();*/

        String newline = System.getProperty("line.separator");
        Scanner console = new Scanner(System.in);

        System.out.print(newline);
        System.out.println("Initializing Main Program." + newline);
        System.out.println("************************** MAIN MENU *************************" + newline);
        System.out.println("Enter Coords \t Enter Relat \t Enter Color \t Enter Shape"+newline);
        System.out.println("Coordinates \t Relation \t Color \t \t Shape" + newline);
        System.out.println("Help \t \t List \t \t Save \t \t Save As" + newline);
        System.out.println("**************************************************************" + newline);

        System.out.print("Enter your selection or type All to enter lines consecutively: ");
        String raw = console.nextLine();

        System.out.println(raw);

        String select = errorCheck(raw);

        if (select.equals("All")){
        }

        if (select.equals("Enter Coords")){
        }

        if (select.equals("Enter Relat")){
        }

        if (select.equals("Enter Color")){
        }

        if (select.equals("Enter Shape")){
        }

        if (select.equals("Coordinates")){
        }

        if (select.equals("Relation")){
        }

        if (select.equals("Color")){
        }

        if (select.equals("Shape")){
        }

        if (select.equals("Help")){
        }

        if (select.equals("List")){
        }

        if (select.equals("Save")){
        }

        if (select.equals("Save As")){
        }
    }

    private static String errorCheck(String raw) {

        String select = raw;
        return select;
    }
}

2 个答案:

答案 0 :(得分:1)

你的问题在于

public class DataSort {...... Global.stop = in.read(); ......} 

因为in.read用于读取整数输入。它不会读取行尾字符。这就是为什么在你输入选择字符串并点击回车后它变得毫无瑕疵。

此致 拉维

答案 1 :(得分:0)

@Sean,这是你的解决方案

在下面注释

public class DataSort
{
.
.
.
//BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
//Scanner console = new Scanner(System.in);
.
.
.
//Global.stop = in.read();
.
.
}

对于Global.stop = in.read(),从相同的输入读缓冲区(可能在同一个类或其他位置)读取并根据需要解析字符串。不要创建另一个输入读缓冲区。

此致 拉维