我需要一些快速帮助完成作业，简而言之，我完成了一项任务，要求我制作一个程序，允许用户pop（），push（）和top（）一个数组。
我做了但是我的导师说代码布局错误，因为我在堆栈类中有System.out.println语句，这些应该在主菜单应用程序中，而堆栈类应该只调用它继承的方法来自数组类。
我认为很公平，我修改了代码，但我现在无法使push（）方法正常工作：/
我知道我需要在菜单app push（）方法中使用Genio.getInteger方法。
有人可以帮忙吗？
Stack Class：
public class Stack extends Array
{
private int x;
public Stack()
{
super();// initialise instance variables
x = 0;
}
public Stack(int newsize)
{
super(newsize);
System.out.println("Stack Created!");
}
/**
* @push user is asked to enter value at keyboard which is then added to the top of the stack
*
*/
public boolean push(int item)
{
return add(item);
}
/**
* @pop removes the current value staored at the top of the stack
*
*/
public int pop()
{
deleteLast();
return getItemback();
}
/**
* @top displays the current value stored at the top of the stack
*
*/
public int top()
{
displayLast();
return getItemback();
}
}
菜单应用：
public static void main()
{
int option;
int item;
Stack s = new Stack();
String []menuitems = {"1 - Display Stack","2 - Pop Stack", "3 - Push Onto Stack","4 - Top Of Stack","5 - Quit Program"};
Menu m = new Menu(menuitems,5);
s.add(12);s.add(2);s.add(1);s.add(13);s.add(24);
do
{
clrscr();
option = m.showMenu();
if ( option == 1 )
{
s.display();
pressKey();
}
if ( option == 2 )
{
if (!s.isEmpty())
System.out.println ("Number Popped: ");
else
System.out.println ("The Stack Is Empty! ");
pressKey();
}
// THIS IS THE PART I CANNOT GET TO WORK!! NOT SURE WHERE/HOW TO CALL PUSH
// METHOD?
if ( option == 3 )
{
item = Genio.getInteger();
if (!s.isFull())
System.out.println("Please Enter Number To be Pushed(" + item + ")");
else
System.out.println("Stack Overflow! ");
pressKey();
}
if ( option == 4 )
{
if (!s.isEmpty())
s.top();
else
System.out.println ("The Stack Is Empty! ");
pressKey();
}
}
while ( option != 5 );
System.out.println("\nDone! \n(You Can Now Exit The Program)\n");
}
/**
* @clrscr removes all text from the screen
*
*/
public static void clrscr()
{
for ( int i=1;i<=50;i++)
System.out.println();
}
/**
* @pressKey requires the user to press return to continue
*
*/
public static void pressKey()
{
String s;
System.out.print("\nPress return to continue : ");
s = Genio.getString();
}
}
编辑：如果相关的Genio课程？：
public class Genio
{
/**
* Constructor for objects of class genio, but nothing needing constructed!
*/
public Genio()
{
}
/**
* getStr() is a private method which safely returns a string for use
* by the public methods getString() and getCharacter() in the class.
*
* @return String for further processing withing the class
*/
private static String getStr()
{
String inputLine = "";
BufferedReader reader =
new BufferedReader(new InputStreamReader(System.in));
try
{
inputLine = reader.readLine();
}
catch(Exception exc)
{
System.out.println ("There was an error during reading: "
+ exc.getMessage());
}
return inputLine;
}
/**
* getInteger() returns an integer value. Exception handling is used to trap
* invalid data - including floating point numbers, non-numeric characters
* and no data. In the event of an exception, the user is prompted to enter
* the correct data in the correct format.
*
* @return validated int value
*/
public static int getInteger()
{
int temp=0;
boolean OK = false;
BufferedReader keyboard = new BufferedReader(new InputStreamReader(System.in));
do
{
try
{
temp = Integer.parseInt(keyboard.readLine());
OK = true;
}
catch (Exception eRef)
{
if (eRef instanceof NumberFormatException)
{
System.out.print("Integer value needed: ");
}
else
{
System.out.println("Please report this error: "+eRef.toString());
}
}
} while(OK == false);
return(temp);
}
/**
* getFloat() returns a floating point value. Exception handling is used to trap
* invalid data - including non-numeric characters and no data.
* In the event of an exception (normally no data or alpha), the user is prompted to enter
* data in the correct format
*
* @return validated float value
*/
public static float getFloat()
{
float temp=0;
boolean OK = false;
BufferedReader keyboard = new BufferedReader(new InputStreamReader(System.in));
do
{
try
{
temp = Float.parseFloat(keyboard.readLine());
OK = true;
}
catch (Exception eRef)
{
if (eRef instanceof NumberFormatException)
{
System.out.print("Number needed: ");
}
else
{
System.out.println("Please report this error: "+eRef.toString());
}
}
} while(OK == false);
return(temp);
}
/**
* getDouble() returns a double precision floating point value.
* Exception handling is used to trap invalid data - including non-numeric
* characters and no data.
* In the event of an exception, the user is prompted to enter
* data in the correct format
*
* @return validated double precision value
*/
public static double getDouble()
{
double temp=0;
boolean OK = false;
BufferedReader keyboard = new BufferedReader(new InputStreamReader(System.in));
do
{
try
{
temp = Double.parseDouble(keyboard.readLine());
OK = true;
}
catch (Exception eRef)
{
if (eRef instanceof NumberFormatException)
{
System.out.print("Number needed: ");
}
else
{
System.out.println("Please report this error: "+eRef.toString());
}
}
} while(OK == false);
return(temp);
}
/**
* getCharacter() returns a character from the keyboard. It does this by
* reading a string then taking the first character read. Subsequent characters
* are discarded without raising an exception.
* The method checks to ensure a character has been entered, and prompts
* if it has not.
*
* @return validated character value
*/
public static char getCharacter()
{
String tempStr="";
char temp=' ';
boolean OK = false;
do
{
try
{
tempStr = getStr();
temp = tempStr.charAt(0);
OK = true;
}
catch (Exception eRef)
{
if (eRef instanceof StringIndexOutOfBoundsException)
{
// means nothing was entered so prompt ...
System.out.print("Enter a character: ");
}
else
{
System.out.println("Please report this error: "+eRef.toString());
}
}
} while(OK == false);
return(temp);
}
/**
* getString() returns a String entered at the keyboard.
* @return String value
*/
public static String getString()
{
String temp="";
try
{
temp = getStr();
}
catch (Exception eRef)
{
System.out.println("Please report this error: "+eRef.toString());
}
return(temp);
}
}
答案 0 :(得分：0)
不确定我是否正确理解了您的问题，但s.push没有被调用？ （s.pop不是？）
如果你要替换
if (!s.isFull())
带
if (!s.isFull() && s.push(item))
有些工作会完成吗？
如果你只希望它是一个提示，请使用大括号（无论如何使用它们，它会让你在一天之内免受可怕的错误）。这样的事情。
if (!s.isFull()) {
System.out.println("enter a number to add");
Scanner sc = new Scanner(System.in);
s.push(sc.nextInt());
}