在读取文件时比较字符串，使用Scanner . hasnext ()， .next

Question

我想为我的程序做一个小高分。该程序有一个LogFile，我想读取该文件并确定获胜者。因为我的程序有一些问题，你可以一遍又一遍地回答同样的问题，并因此获得学分。使用下面的代码，我试图防止作弊得分。我试着比较第三，第四和第五个字符串，这代表了你必须解决的计算。当下一行具有相同的计算时，我想忽略hilicore的计数有人能帮我一下吗?我只得到一堆错误。

谢谢你的时间和帮助。

public int readFile() {
    String score = null;
    while (scan.hasNext()) {
        String a = scan.next();
        String b = scan.next();
        String c = scan.next();
        String d = scan.next();
        String e = scan.next();
        String f = scan.next();
        String g = scan.next();
        String h = scan.next();
        String i = scan.next();
        if (c.equals(scan.next()) && d.equals(scan.next()) && e.equals(scan.next())) {
        } else {
            temp = Integer.parseInt(i);
            if (temp > highscore) {
                highscore = temp;
            }
        }
    }
    return highscore;
}

文本文件:

    014/07/29 08:25:15  95 + 80 4       false       -171        0
    2014/07/29 08:25:15 95 + 80 4       false       -171        0
    2014/07/29 08:25:49 8 * 3   24      true        0       1
    2014/07/29 08:25:49 8 * 3   24      true        0       2
    2014/07/29 08:25:49 8 * 3   24      true        0       3
    2014/07/29 08:25:50 8 * 3   24      true        0       4
    2014/07/29 08:25:50 8 * 3   24      true        0       5

错误:

Exception in thread "AWT-EventQueue-0" java.lang.NumberFormatException: For input string: "2014/07/28"
    at java.lang.NumberFormatException.forInputString(Unknown Source)
    at java.lang.Integer.parseInt(Unknown Source)
    at java.lang.Integer.parseInt(Unknown Source)
    at mathe.Highscore.readFile(Highscore.java:42)
    at mathe.Gui$TestActionListener.actionPerformed(Gui.java:231)
    at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
    at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
    at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
    at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
    at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
    at java.awt.Component.processMouseEvent(Unknown Source)
    at javax.swing.JComponent.processMouseEvent(Unknown Source)
    at java.awt.Component.processEvent(Unknown Source)
    at java.awt.Container.processEvent(Unknown Source)
    at java.awt.Component.dispatchEventImpl(Unknown Source)
    at java.awt.Container.dispatchEventImpl(Unknown Source)
    at java.awt.Component.dispatchEvent(Unknown Source)
    at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
    at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
    at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
    at java.awt.Container.dispatchEventImpl(Unknown Source)
    at java.awt.Window.dispatchEventImpl(Unknown Source)
    at java.awt.Component.dispatchEvent(Unknown Source)
    at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
    at java.awt.EventQueue.access$200(Unknown Source)
    at java.awt.EventQueue$3.run(Unknown Source)
    at java.awt.EventQueue$3.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
    at java.awt.EventQueue$4.run(Unknown Source)
    at java.awt.EventQueue$4.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
    at java.awt.EventQueue.dispatchEvent(Unknown Source)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.run(Unknown Source)

Answer 1

如果你继续使用scan。接下来，在条件语句中，扫描器将扫描下一个值。我认为你想要获取下一个值并将其用于比较。

public int readFile() {
    String score = null;
    while (scan.hasNext()) {
        String a = scan.next();
        String b = scan.next();
        String c = scan.next();
        String d = scan.next();
        String e = scan.next();
        String f = scan.next();
        String g = scan.next();
        String h = scan.next();
        String i = scan.next();
        String nextVal = scan.next();
        if (c.equals(nextVal) && d.equals(nextVal) && e.equals(nextVal)) {
        } else {
            temp = Integer.parseInt(i);
            if (temp > highscore) {
                highscore = temp;
            }
        }
    }
    return highscore;
}

我希望这对你有帮助。干杯. . !

Answer 2

在if语句中调用scan.next()是个坏主意。第二次扫描。Next只在第一个等于为真时调用，第二个等于为真时调用，因此很容易混淆要读的列。移动扫描。对于初学者，if语句的下一个。

从错误消息中，您正在调用日期字符串上的Integer.parseInt(i);。

看起来你正在试图找到文件中最大的数字?你应该做的是存储最高的int值，它在循环外声明。例如

int Highscore = 0;
while (...) {
   .... 
  int num = Integer.parseInt(i);
  if (num > Highscore) {
    Highscore = num;
  } 

如果你明白我的意思。