java - 如何修复java错误？

因此，我必须创建一个程序，在其中使用多态性和继承来创建指向左箭头和箭头的箭头，而我做到了。但是，当我创建主类并尝试调用方法时，例如说“ LeftArrow.drawHere”来绘制箭头，我得到了错误，说我不能从类LeftArrow中静态引用非静态字段“ drawHere（）” ”。我当时想知道是否不能这样做，如何设计主要方法以绘制箭头？
这是我的代码，请注意有几个类，但是我将在这里发布所有这些类。

import java.util.Scanner;

public class LeftArrow extends ShapeBasic
{
    private int tail, width;
    private static int inside;
    public LeftArrow()
    {
        super();
        tail = 0;
        width = 0;
    }
    public LeftArrow(int noff, int ntail, int nwidth)
    {
        super(noff);
        tail = ntail;
        setWidth(nwidth);
    }

    public void setTail(int ntail)
    {
        tail = ntail;
    }

    public int getTail()
    {
        return tail;
    }
    public void setWidth(int nwidth)
    {
        if (nwidth % 2 == 1)
        {
            width = nwidth;
        }
        else
        {
            System.out.println(" Width must be odd");
            System.out.println("Enter a new width");
            Scanner key = new Scanner(System.in);
            int wid = key.nextInt();
            setWidth(wid);
        }
    }
    public int getWidth()
    {
        return width;
    }
    public void drawHere()
    {
        drawTriangle();
        drawTail();
        drawBTriangle();
        //System.out.println();
    }
    public void drawTriangle()
    {
        inside = 1;
        int split = (width/2);
        skipSpaces(getOffset());
        System.out.println('*');
        for(int count = 0; count < split; count ++)
        {
            skipSpaces(getOffset() - (inside + 1));
            System.out.print('*');
            skipSpaces(inside);
            System.out.print('*');
            inside = inside + 2;
            System.out.println();
        }
    }
    public void drawTail()
    {
        skipSpaces(getOffset() - getInside() - 1);
        System.out.print('*');
        skipSpaces(getInside());
        for (int count = 0; count < tail ; count++)
        {
            System.out.print('*');
        }
    }
    public void drawBTriangle()
    {
        int inside = getInside();
        int split = (width/2);
        System.out.println();
        for(int count = 0; count < split; count ++)
        {
            skipSpaces(getOffset() - (inside - 1));
            System.out.print('*');
            inside = inside - 2;
            skipSpaces(inside);
            System.out.print('*');
            System.out.println();
        }
        skipSpaces(getOffset());
        System.out.print('*');
    }
    public int getInside()
    {
        return inside;
    }
    private static void skipSpaces(int number)
    {
        for (int count = 0; count < number; count++)
            System.out.print(' ');
    }
    @Override
    public void setOffset(int noff) {
        // TODO Auto-generated method stub

    }
    @Override
    public int getOffset() {
        // TODO Auto-generated method stub
        return 0;
    }
}

import java.util.Scanner;

public class RightArrow extends ShapeBasic
{
    private int tail, width;
    private static int inside;
    public RightArrow()
    {
        super();
        tail = 0;
        width = 0;
    }
    public RightArrow(int noff, int ntail, int nwidth)
    {
        super(noff);
        tail = ntail;
        setWidth(nwidth); // must be odd
    }
    public void setTail(int ntail)
    {
        tail = ntail;
    }
    public int getTail()
    {
        return tail;
    }
    public void setWidth(int nwidth)
    {
        if (nwidth % 2 == 1)
        {
            width = nwidth;
        }
        else
        {
            System.out.println(" Width must be odd");
            System.out.println("Enter a new width");
            Scanner key = new Scanner(System.in);
            int wid = key.nextInt();
            setWidth(wid);
        }
    }
    public int getWidth()
    {
        return width;
    }
    public void drawHere()
    {
        drawTriangle();
        drawTail();
        drawBTriangle();
        System.out.println();
    }
    public void drawTail()
    {
        skipSpaces(getOffset() + 1);
        for (int count = 0; count < tail ; count++)
        {
            System.out.print('*');
        }
        skipSpaces(getInside());
        System.out.print('*');  // fix
    }
    public void drawTriangle()
    {
        inside = 1;
        int split = (width/2);
        skipSpaces(getOffset() + tail);
        System.out.println('*');
        for(int count = 0; count < split; count ++)
        {
            skipSpaces(getOffset() + tail);
            System.out.print('*');
            skipSpaces(inside);
            System.out.print('*');
            inside = inside + 2;
            System.out.println();
        }
    }
    public void drawBTriangle()
    {
        int inside = getInside();
        int split = (width/2);
        System.out.println();
        for(int count = 0; count < split; count ++)
        {
            skipSpaces(getOffset() + tail);
            System.out.print('*');
            inside = inside - 2;
            skipSpaces(inside);
            System.out.print('*');
            System.out.println();
        }
        skipSpaces(getOffset() + tail);
        System.out.print('*');
    }
    public int getInside()
    {
        return inside;
    }
    private static void skipSpaces(int number)
    {
        for (int count = 0; count < number; count++)
            System.out.print(' ');
    }
}

public abstract class ShapeBase implements ShapeInterface {
    private int offset;
    public abstract void drawHere();


    public void drawAt(int lineNumber) {
        for (int count = 0; count < lineNumber; count++)
            System.out.println();
        drawHere();
    }
}

public class ShapeBasic implements ShapeInterface
{

    private int offset;

    public ShapeBasic()
    {
        offset = 0;
    }
    public ShapeBasic( int noff)
    {
        offset = noff;
    }
    public void setOffset(int noff)
    {
        offset = noff;
    }

    public int getOffset()
    {
        return offset;
    }

    public void drawAt(int linnumber)
    {
        for (int count = 0; count < linnumber; count++)
            System.out.println();
        drawHere();
    }

    public void drawHere()
    {
        for (int count = 0; count < offset; count++)
            System.out.print(' ');
        System.out.println('*');
    }

}

public interface ShapeInterface
{
    public void setOffset(int noff);    // set how many space from left

    public int getOffset(); // returns offset
    public void drawAt(int linnumber);  // moves down equal to line number Ex. 5 = 5 down
    public void drawHere(); // draws shape after moving left equal to offset
}

最佳答案

我想要看看您的主要方法，但是我没有声誉。
猜测一下，也许您实际上不是在您的main方法中实例化这些类的对象，而是尝试从它们中调用这些方法。例如，如果您这样做：

LeftArrow lArrow = new LeftArrow();
lArrow.drawHere();

它应该工作。