java - JComboBox 类型不是通用的；它不能用参数 <Object> 参数化

Question

我有一个 Java 项目代码，其中一个类如下所示，但是当我想运行这段代码时，我会在这个类中遇到编译错误，其中一部分代码是:

package othello.view;

import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.BorderFactory;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.border.Border;
import javax.swing.border.EmptyBorder;

import othello.ai.ReversiAI;
import othello.controller.AIControllerSinglePlay;
import othello.controller.AIList;
import othello.model.Board;
import othello.model.Listener;

@SuppressWarnings("serial")
public class TestFrameAIVSAI extends JFrame implements ActionListener, Logger,
        Listener {
    private static Border THIN_BORDER = new EmptyBorder(4, 4, 4, 4);

    public JComboBox<Object> leftAICombo;
    public JComboBox<Object> rightAICombo;
    private JButton startTest;
    private JButton pauseTest;

错误来自两行public JComboBox<Object> leftAICombo;和 public JComboBox<Object> rightAICombo;错误是:

The type JComboBox is not generic; it cannot be parameterized with arguments <Object>

问题是什么？

Answer 1

改变下面几行

   public JComboBox<Object> leftAICombo;
   public JComboBox<Object> rightAICombo;

到

public JComboBox leftAICombo;
public JComboBox rightAICombo;

在这里JComboBox<Object>仅在 java7 中引入的类型参数。如果您使用低于 7 的 jdk，则会出错