Java代码中Button报错的地方让我很疑惑

Question

package frame;

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.FlowLayout;
import java.awt.Frame;
import java.awt.LayoutManager;

public class Button {

    public static void main(String[] args) {
        // TODO Auto-generated method stub 
         Frame frame=new Frame();
         Button button1=new Button("button1");
         Button button2=new Button("button2");
         Button button3=new Button("button3");
         //初始化面板
         //按钮在容器中靠左显示
         frame.setLayout(new FlowLayout(FlowLayout.LEFT));
         frame.setBounds(200,200,400,400);
         frame.setBackground(new Color(33, 104, 229));
         //设置可见
         frame.setVisible(true);
         frame.add(button1);
         frame.add(button2);
         frame.add(button3);

    }

}

为什么报错会在Button那，必须要我创建一个Button函数