import java.awt.Component;import java.awt.Dimension;import java.awt.GridBagConstraints;import java.awt.GridBagLayout;import javax.swing.BorderFactory;import javax.swing.Box;import javax.swing.BoxLayout;import javax.swing.DefaultListModel;import javax.swing.JButton;import javax.swing.JFrame;import javax.swing.JLabel;import javax.swing.JList;import javax.swing.JPanel;import javax.swing.JScrollPane;import javax.swing.JTable;import javax.swing.ListSelectionModel;import javax.swing.table.DefaultTableModel;public class BOX3 {	static JPanel topPanel;	static JPanel middlePanel; 	static JPanel bottomPanel; 	static void createTopPanel() { 		topPanel = new JPanel(); 		String[] columnName = { "姓名", "性别", "单位", "参加项目", "备注" }; 		String[][] rowData = { { "张三", "男", "计算机系", "100 米 ,200 米", "" }, 				{ "李四", "男", "化学系", "100 米，铅球", "" }, 		}; 		// 创建表格		JTable table = new JTable(new DefaultTableModel(rowData, columnName)); 		// 创建包含表格的滚动窗格		JScrollPane scrollPane = new JScrollPane(table);		scrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS); 		// 定义 topPanel 的布局为 BoxLayout，BoxLayout 为垂直排列		topPanel.setLayout(new BoxLayout(topPanel, BoxLayout.Y_AXIS)); 		// 先加入一个不可见的 Strut，从而使 topPanel 对顶部留出一定的空间		topPanel.add(Box.createVerticalStrut(10)); 		// 加入包含表格的滚动窗格 		topPanel.add(scrollPane); 		// 再加入一个不可见的 Strut，从而使 topPanel 和 middlePanel 之间留出一定的空间		topPanel.add(Box.createVerticalStrut(10)); 	}	static void createMiddlePanel() { 		// 创建 middlePanel 		middlePanel = new JPanel(); 		// 采用水平布局		middlePanel .setLayout(new BoxLayout(middlePanel,BoxLayout.X_AXIS )); 		// 创建标签运动会项目				JLabel sourceLabel = new JLabel("运动会项目："); 		sourceLabel.setAlignmentY(Component.TOP_ALIGNMENT ); 		sourceLabel.setBorder(BorderFactory.createEmptyBorder (4, 5, 0, 5)); 		// 创建列表运动会项目		DefaultListModel listModel = new DefaultListModel(); 		listModel.addElement("100 米"); 		listModel.addElement("200 米"); 		listModel.addElement("400 米"); 		listModel.addElement("跳远"); 		listModel.addElement("跳高"); 		listModel.addElement("铅球"); 		JList sourceList = new JList(listModel); 		sourceList.setSelectionMode(ListSelectionModel.MULTIPLE_INTERVAL_SELECTION ); 		sourceList.setVisibleRowCount(5); 		JScrollPane sourceListScroller = new JScrollPane(sourceList); 		sourceListScroller.setPreferredSize(new Dimension(120, 80)); 		sourceListScroller 		.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS ); 		sourceListScroller.setAlignmentY(Component.TOP_ALIGNMENT ); 		// 创建最左边的 Panel 		JPanel sourceListPanel = new JPanel(); 		// 最左边的 Panel 采用水平布局		sourceListPanel.setLayout(new BoxLayout(sourceListPanel,BoxLayout.X_AXIS )); 		// 加入标签到最左边的 Panel 		sourceListPanel.add(sourceLabel); 		// 加入列表运动会项目到最左边的 Panel 		sourceListPanel.add(sourceListScroller); 		sourceListPanel.setAlignmentY(Component.TOP_ALIGNMENT ); 		sourceListPanel.setBorder(BorderFactory.createEmptyBorder (0, 0, 0, 30)); 		// 将最左边的 Panel 加入到 middlePanel 		middlePanel .add(sourceListPanel); 		// 定义中间的两个按钮				JButton toTargetButton = new JButton(">>"); 		JButton toSourceButton = new JButton("<<"); 		// 定义中间的 Panel 		JPanel buttonPanel = new JPanel(); 		// 中间的 Panel 采用水平布局		buttonPanel.setLayout(new BoxLayout(buttonPanel, BoxLayout.Y_AXIS )); 		// 将按钮 >> 加入到中间的 Panel 		buttonPanel.add(toTargetButton); 		//两个按钮之间加入一个不可见的 rigidArea					buttonPanel.add(Box.createRigidArea (new Dimension(15, 15))); 		// 将按钮 << 加入到中间的 Panel 		buttonPanel.add(toSourceButton); 		buttonPanel.setAlignmentY(Component.TOP_ALIGNMENT ); 		buttonPanel.setBorder(BorderFactory.createEmptyBorder (15, 5, 15, 5)); 		// 将中间的 Panel 加入到 middlePanel 		middlePanel .add(buttonPanel); 		// 创建标签查询项目		JLabel targetLabel = new JLabel("查询项目："); 		targetLabel.setAlignmentY(Component.TOP_ALIGNMENT ); 		targetLabel.setBorder(BorderFactory.createEmptyBorder (4, 5, 0, 5)); 		// 创建列表查询项目					DefaultListModel targetListModel = new DefaultListModel(); 		targetListModel.addElement("100 米"); 		JList targetList = new JList(targetListModel); 		targetList 		.setSelectionMode(ListSelectionModel.MULTIPLE_INTERVAL_SELECTION ); 		targetList.setVisibleRowCount(5); 		JScrollPane targetListScroller = new JScrollPane(targetList); 		targetListScroller.setPreferredSize(new Dimension(120, 80)); 		targetListScroller 		.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS ); 		targetListScroller.setAlignmentY(Component.TOP_ALIGNMENT ); 		// 创建最右边的 Panel 		JPanel targetListPanel = new JPanel(); 		// 设置最右边的 Panel 为水平布局		targetListPanel.setLayout(new BoxLayout(targetListPanel,BoxLayout.X_AXIS )); 		// 将标签查询项目加到最右边的 Panel 		targetListPanel.add(targetLabel); 		// 将列表查询项目加到最右边的 Panel 		targetListPanel.add(targetListScroller); 		targetListPanel.setAlignmentY(Component.TOP_ALIGNMENT ); 		targetListPanel.setBorder(BorderFactory.createEmptyBorder (0, 30, 0, 0)); 		// 最后将最右边的 Panel 加入到 middlePanel 		middlePanel .add(targetListPanel); 	}	static void createBottomPanel() { 		// 创建查询按钮		JButton actionButton = new JButton("查询"); 		// 创建退出按钮		JButton closeButton = new JButton("退出"); 		// 创建 bottomPanel 		bottomPanel = new JPanel(); 		// 设置 bottomPanel 为垂直布局		bottomPanel .setLayout(new BoxLayout(bottomPanel,BoxLayout.Y_AXIS )); 		// 创建包含两个按钮的 buttonPanel 		JPanel buttonPanel = new JPanel(); 		// 设置 bottomPanel 为水平布局		buttonPanel.setLayout(new BoxLayout(buttonPanel, BoxLayout.X_AXIS )); 		// 将查询按钮加入到 buttonPanel 		buttonPanel.add(actionButton); 		//加入一个 glue, glue 会挤占两个按钮之间的空间					buttonPanel.add(Box.createHorizontalGlue ()); 		// 将退出按钮加入到 buttonPanel 		buttonPanel.add(closeButton); 		// 加入一个 Strut，从而使 bottomPanel 和 middlePanel 上下之间留出距离		bottomPanel .add(Box.createVerticalStrut (10)); 		// 加入 buttonPanel 		bottomPanel .add(buttonPanel); 		// 加入一个 Strut，从而使 bottomPanel 和底部之间留出距离		bottomPanel .add(Box.createVerticalStrut (10)); 	}	public static void main(String[] args) { 		// 创建 topPanel 		createTopPanel (); 		// 创建 middlePanel 		createMiddlePanel (); 		// 创建 bottomPanel 		createBottomPanel (); 		// 创建包含 topPanel，middlePanel 和 bottomPanel 的 panelContainer 		JPanel panelContainer = new JPanel(); 		//panelContainer 的布局为 GridBagLayout 		panelContainer.setLayout(new GridBagLayout()); 		GridBagConstraints c1 = new GridBagConstraints(); 		c1.gridx = 0; 		c1.gridy = 0; 		c1.weightx = 1.0; 		c1.weighty = 1.0; 		c1.fill = GridBagConstraints.BOTH ; 		// 加入 topPanel 		panelContainer.add(topPanel,c1); 		GridBagConstraints c2 = new GridBagConstraints(); 		c2.gridx = 0; 		c2.gridy = 1; 		c2.weightx = 1.0; 		c2.weighty = 0; 		c2.fill = GridBagConstraints.HORIZONTAL ; 		// 加入 middlePanel 		panelContainer.add(middlePanel,c2); 		GridBagConstraints c3 = new GridBagConstraints(); 		c3.gridx = 0; 		c3.gridy = 2; 		c3.weightx = 1.0; 		c3.weighty = 0; 		c3.fill = GridBagConstraints.HORIZONTAL ; 		// 加入 bottomPanel 		panelContainer.add(bottomPanel,c3); 		// 创建窗体		JFrame frame = new JFrame("Boxlayout 演示"); 		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE ); 		panelContainer.setOpaque(true); 		frame.setSize(new Dimension(480, 320)); 		frame.setContentPane(panelContainer); 		frame.setVisible(true); 	}}