pagingcomponent.java

一个JAVA分页解决方案

package com.ctic.core.pub.ui;

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFormattedTextField;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.WindowConstants;
import javax.swing.border.BevelBorder;
import javax.swing.text.DefaultFormatterFactory;
import javax.swing.text.NumberFormatter;

import com.jgoodies.forms.layout.CellConstraints;
import com.jgoodies.forms.layout.FormLayout;

/**
 * 用于进行翻页的控件，该控件建立了这样一种机制：根据用户的翻页请求，从<code>IPagingWorker</code>中取得相应的记录，并
 * 显示到<code>IPagingViewer</code>中。而通过<code>PagingHelper</code>，用户可以简单方便的创建实用的<code>IPagingViewer</code>
 * 和<code>IPagingWorker</code>。<br>
 * <p>典型使用方式如下：<pre><code>
 * 	PagingComponent pagiComp = new PagingComponent();
 * 	pagiComp.setPageSize(12);
 * 	pagiComp.setPagingViewer(PagingHelper.createPagingViewerFor(mTable));
 * 	pagiComp.setPagingWorker(PagingHelper.createPagingWorkerFor(client.query(params)));(或
 * 	pagiComp.setPagingWorker(PagingHelper.createPagingWorkerFor(ModuleIDs.MODULE_PROD, "productService", 
 * 		"queryProductList", new Class[]{Product.class}, new Object[]{paraObj}));)
 * 	...
 * </code></pre>
 * 控件运行显示时大体效果如下：<br><strong>	"|<< |< 21-30 /65 >| >>| [3]/20 GO" </strong>
 * <p>
 * @author Tu_Minglei
 */
public class PagingComponent extends JPanel {
	private JLabel	firstPageLabel;
	private JLabel	prevPageLabel;
	private JLabel	curScopeLabel;
	private JLabel	nextPageLabel;
	private JLabel	lastPageLabel;
	private JFormattedTextField pageNoFld;
	private JLabel	tatalPagesLabel;
	private JButton	turnToPageBtn;
	
	private IPagingViewer 	pagingViewer;
	private IPagingWorker 	pagingWorker;
	
	private	int		pageSize = 10;
	private int 	totalRecordCount;
	private int		currentPageNo;
	
	private Map<JComponent,Boolean> compEnableMap = new HashMap<JComponent, Boolean>();//存储控件的可用状态信息
	
	public PagingComponent(){
		initializePagingUI();	
		refreshComponents();
	}

	public int getPageSize() {
		return pageSize;
	}

	/**
	 * 设置分页大小(每分页的记录数，默认值是10)
	 * @param pageSize
	 * @return
	 */
	public PagingComponent setPageSize(int pageSize) {
		this.pageSize = pageSize;
    	showRecords(gotoPage(1));
		return this;
	}

	public IPagingWorker getPagingWorker() {
		return pagingWorker;
	}

	/**
	 * 设置实际提供分页记录及相关信息的<code>IPagingWorker</code>实现
	 * @param pagination
	 */
	public PagingComponent setPagingWorker(IPagingWorker pagingWorker) {
		this.pagingWorker = pagingWorker;
		this.totalRecordCount = pagingWorker.getTatalRecordCount();
		refreshComponents();		
    	showRecords(gotoPage(1));
    	return this;
	}

	public IPagingViewer getPagingViewer() {
		return pagingViewer;
	}

	/**
	 * 设置用于显示分页记录的<code>IPagingViewer</code>实现
	 * @param pagingViewer
	 */
	public PagingComponent setPagingViewer(IPagingViewer pagingViewer) {
		this.pagingViewer = pagingViewer;
    	showRecords(gotoPage(1));	
		return this;
	}

	/**==================================================================*/
	private void initializePagingUI() {
		firstPageLabel = new JLabel("|<<");
		prevPageLabel  = new JLabel("|<");
		curScopeLabel  = new JLabel("0-0 /0");
		nextPageLabel  = new JLabel(">|");
		lastPageLabel  = new JLabel(">>|");
		pageNoFld = new JFormattedTextField();
		tatalPagesLabel= new JLabel("/0");
		turnToPageBtn  = new JButton("GO");
		
		pageNoFld.setFormatterFactory(new DefaultFormatterFactory(new NumberFormatter()));
		
		addMouseListenerFor(firstPageLabel);
		addMouseListenerFor(prevPageLabel);
		addMouseListenerFor(nextPageLabel);
		addMouseListenerFor(lastPageLabel);
		addActionListenerFor(turnToPageBtn);
		
		String columnSpecStr = "7dlu:grow, " +					//for overhead space
							   "fill:max(21;pref), 3dlu, " +	//for |<<
							   "fill:max(21;pref), 5dlu, " +	//for |<
							   "center:max(30;pref), 5dlu, " +	//for current record scope
							   "fill:max(21;pref), 3dlu, " +	//for >|
							   "fill:max(21;pref), 7dlu, " +	//for >>|
							   "fill:max(30;pref), " +			//for input field
							   "left:pref, " +					//for total pages label
							   "3dlu, pref";					//for "go" button
		
		setLayout(new FormLayout(columnSpecStr, "pref"));
		
		CellConstraints cc = new CellConstraints();
		add(firstPageLabel,cc.xy(2, 1));
		add(prevPageLabel, cc.xy(4, 1));
		add(curScopeLabel, cc.xy(6, 1));
		add(nextPageLabel, cc.xy(8, 1));
		add(lastPageLabel, cc.xy(10, 1));
		add(pageNoFld, cc.xy(12, 1));
		add(tatalPagesLabel,cc.xy(13, 1));
		add(turnToPageBtn, cc.xy(15, 1));
	}
	
	/**
	 * 更新控件内部状态
	 */
	protected void refreshComponents(){
		compEnableMap.put(firstPageLabel,hasPage(currentPageNo - 1));
		compEnableMap.put(prevPageLabel, hasPage(currentPageNo - 1));
		compEnableMap.put(nextPageLabel, hasPage(currentPageNo + 1));
		compEnableMap.put(lastPageLabel, hasPage(currentPageNo + 1));
		compEnableMap.put(turnToPageBtn, true);
		
		initializeLabel(firstPageLabel);
		initializeLabel(prevPageLabel);
		initializeLabel(nextPageLabel);
		initializeLabel(lastPageLabel);
		
		pageNoFld.setText(""+currentPageNo);
		curScopeLabel.setText(curFirstRecordNo()+"-"+curLastRecordNo()+" /"+totalRecordCount+" ");
		tatalPagesLabel.setText("/"+totalPageCount());
	}
	
	/**-----------------------------------------------------------------*/
	private void addMouseListenerFor(final JLabel label){
		label.addMouseListener(new MouseAdapter(){
		    public void mouseEntered(MouseEvent e) {
		    	activateLabel(label);
		    }
		    public void mouseExited(MouseEvent e) {
		    	passivateLabel(label);
		    }
		    public void mouseClicked(MouseEvent e) {
		    	pageTurning(label);
		    }
		});
		
	}
	
	private void addActionListenerFor(final JButton turnToBtn){
		turnToBtn.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e) {
		    	pageTurning(turnToBtn);
			}			
		});
	}
	
	private void initializeLabel(JLabel label){
		passivateLabel(label);
	}
	
	/**
	 * 激活显示指定标签
	 * @param label
	 */
	private void activateLabel(JLabel label){
		if(compEnableMap.get(label)){
			label.setFont(new Font(label.getFont().getName(), Font.BOLD, label.getFont().getSize()));
			label.setForeground(Color.BLUE);
			label.setBorder(new BevelBorder(BevelBorder.RAISED));
		}else{
			label.setFont(new Font(label.getFont().getName(), Font.BOLD, label.getFont().getSize()));
			label.setForeground(Color.DARK_GRAY);
//			label.setBorder(new BevelBorder(BevelBorder.RAISED));
		}
	}
	
	/**
	 * 钝化显示指定标签
	 * @param label
	 */
	private void passivateLabel(JLabel label){
		if(compEnableMap.get(label)){
			label.setFont(new Font(label.getFont().getName(), Font.PLAIN, label.getFont().getSize()));
			label.setForeground(Color.BLACK);
			label.setBorder(null);
		}else{
			label.setFont(new Font(label.getFont().getName(), Font.PLAIN, label.getFont().getSize()));
			label.setForeground(Color.GRAY);
			label.setBorder(null);
		}
	}
	
	/**
	 * 根据事件来源的不同，实际执行翻页及相关操作的方法
	 * @param sourceComp
	 */
	private void pageTurning(JComponent sourceComp){
    	if(!compEnableMap.get(sourceComp)) return;	//来源控件的状态为不可用，忽略翻页命令
    	
		if(sourceComp == firstPageLabel){
    		showRecords(gotoPage(1));
    		sourceComp.setBorder(new BevelBorder(BevelBorder.LOWERED));
		}
		if(sourceComp == prevPageLabel){
    		showRecords(gotoPage(currentPageNo -1));
    		sourceComp.setBorder(new BevelBorder(BevelBorder.LOWERED));
		}
		if(sourceComp == nextPageLabel){
    		showRecords(gotoPage(currentPageNo +1));
    		sourceComp.setBorder(new BevelBorder(BevelBorder.LOWERED));
		}
		if(sourceComp == lastPageLabel){
    		showRecords(gotoPage(totalPageCount()));
    		sourceComp.setBorder(new BevelBorder(BevelBorder.LOWERED));
		}
		if(sourceComp == turnToPageBtn && pageNoFld.getValue() != null){
    		int pageNo = ((Long)pageNoFld.getValue()).intValue();
    		showRecords(gotoPage(pageNo));
		}
	}
	
	/**++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*
	 * 							接口及内部类
	 **++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
	/**
	 * 以备控件自动调用的用于显示相应结果记录的接口
	 * 
	 * @author Tu_Minglei
	 */
	public interface IPagingViewer {
		/**
		 * 显示传入的记录
		 * @param records
		 */
		void showRecords(List records);
	}
	
	/**--------------------------------------------------------------*/
	/**
	 * 实际获取指定范围记录及提供相关信息的接口
	 * 
	 * @author Tu_Minglei
	 */
	public interface IPagingWorker {
		/**
		 * 获得总记录数
		 * @return
		 */
		int	 getTatalRecordCount();
		/**
		 * 获得指定范围的记录
		 * @param startRowNo
		 * @param count
		 * @return
		 */
		List getRecords(int startRowNo, int count);
	}

	/**+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*
	 * 							用于分页操作的助手方法 
	 **+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
	protected int totalPageCount() {
		return (totalRecordCount <= 0) ? 0 : (totalRecordCount/pageSize + 1);
	}

	protected int curFirstRecordNo() {
		return (totalRecordCount <= 0) ? 0 : ((currentPageNo - 1) * pageSize + 1);
	}

	protected int curLastRecordNo() {
		return Math.min((currentPageNo * pageSize), totalRecordCount);
	}

	protected boolean hasPage(int pageNo) {
		return (pageNo > 0 && pageNo <= totalPageCount());
	}

	protected List gotoPage(int pageNo) {
		int firstRow = (pageNo - 1) * pageSize + 1;
		List records = getRecords(firstRow, pageSize);
		this.currentPageNo = pageNo;
		refreshComponents();
		return records;
	}

	private List getRecords(int firstRowNo, int count){
		return (pagingWorker == null) ? null : pagingWorker.getRecords(firstRowNo, count);
	}
	
	private void showRecords(List records) {
		if(pagingViewer != null) pagingViewer.showRecords(records);
	}

	// *****************************************************************
	public static void main(String[] args) {
		JFrame frame = new JFrame();
		frame.setPreferredSize(new Dimension(600, 60));
		frame.setLocation(100, 100);
		frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
		frame.add(new PagingComponent(), BorderLayout.CENTER);
		frame.pack();
		frame.setVisible(true);
	}

}