frmmain.java

该压缩文件中共包含16个非常实用的java学习实例

import java.applet.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
public class FrmMain extends Frame implements  ActionListener
{
	private Canvas c1;
	private Canvas c2;
	
	private JButton b1;
	private JButton b2;
	private JButton b3;
	
	private JPanel p;
	private JPanel p1;
	
	private Graphics g1;
	private Graphics g2;
	
	private Image m1;
	private Image m2;
	
	private FileInputStream f1=null;
	private FileInputStream f2=null;
	
	private String filepath1=null;
	private String filepath2=null;
	
	private byte bit1[]=new byte[1];
	private byte bit2[]=new byte[1];
	
		
	public  FrmMain()
	{
		c1=new Canvas();
		c2=new Canvas();
		c1.setSize(180,220);
		c2.setSize(180,220);
		FlowLayout fl=new FlowLayout(1,10,10);
		p1=new JPanel(fl);
		
		p1.add(c1);
		p1.add(c2);
		
		b1=new JButton("选择第一幅图片");
		b2=new JButton("选择第二幅图片");
		b3=new JButton("开始比较");
		b1.setFont(new Font("DialogInput", 0, 12));
		b2.setFont(new Font("DialogInput", 0, 12));
		b3.setFont(new Font("DialogInput", 0, 12));
		p=new JPanel();
		this.setLayout(new BorderLayout());
		this.add("Center",p1);
		this.add("South",p);
		
		p.add(b1);
		p.add(b2);
		p.add(b3);

		b1.addActionListener(this);
		b2.addActionListener(this);
		b3.addActionListener(this);
		
		//m1=Toolkit.getDefaultToolkit().getImage("样品.jpg");
		
		this.setTitle("图片比较");
		this.setSize(400,300);
		this.setResizable(false);
		Dimension d=Toolkit.getDefaultToolkit().getScreenSize();
		Dimension f=this.getSize();
		this.setLocation(d.width/2-f.width/2,d.height/2-f.height/2);
		this.show();
		this.addWindowListener(new WindowAdapter()
		{
			public void windowClosing(WindowEvent evt)
			{
				System.exit(0);
			}
		});
		
		this.init();
	}
	public void init()
	{
		g1=c1.getGraphics();
		g2=c2.getGraphics();
		
		g1.draw3DRect(0,0,c1.getWidth()-1,c1.getHeight()-1,true);
		g2.draw3DRect(0,0,c2.getWidth()-1,c2.getHeight()-1,true);
	}

	public static void main(String[] args)
	{
		FrmMain app=new FrmMain();
	}

	public void actionPerformed(ActionEvent e) 
	{
		if(e.getActionCommand().equals("选择第一幅图片"))
		{
			FileDialog fdlg=new FileDialog(new Frame(),"选择第一幅图片",FileDialog.LOAD);
			fdlg.setVisible(true);
			filepath1=fdlg.getDirectory()+fdlg.getFile();
			m1=Toolkit.getDefaultToolkit().getImage(filepath1);
			g1.drawImage(m1,0,0,c1.getWidth()-1,c1.getHeight()-1,Color.BLUE,this);
		}
		else if(e.getActionCommand().equals("选择第二幅图片"))
		{
			FileDialog fdlg=new FileDialog(new Frame(),"选择第一幅图片",FileDialog.LOAD);
			fdlg.setVisible(true);
			filepath2=fdlg.getDirectory()+fdlg.getFile();
			m2=Toolkit.getDefaultToolkit().getImage(filepath2);
			g2.drawImage(m2,0,0,c2.getWidth(),c2.getHeight(),Color.BLUE,this);
			
		}
		else
		{
			//System.out.println(filepath1);
			if(filepath1==null||filepath2==null)
				{
					JOptionPane.showMessageDialog(null,"请选择2张要比较的图片","错误",JOptionPane.ERROR_MESSAGE);
					return;
				}
			if(filepath1.equals("")||filepath2.equals(""))
				{
					JOptionPane.showMessageDialog(null,"请选择2张要比较的图片","错误",JOptionPane.ERROR_MESSAGE);
					return;
				}
			try
			{
				f1=new FileInputStream(filepath1);
				f2=new FileInputStream(filepath2);
				int i1,i2;
				String str="";
				while(true)
				{
					i1=f1.read(bit1);
					i2=f2.read(bit2);
					if(i1!=i2)
					{
						str="图片大小不相等！！！";
						break;
					}
					if(bit1[0]!=bit2[0])
					{
						str="图片内容不相等！！！";
						break;
					}
					
					if(i1==-1||i2==-1)
					{
						str="此2张图片完全相等！！！";
						break;
					}
				}
				JOptionPane.showMessageDialog(null,str,"结果显示",JOptionPane.INFORMATION_MESSAGE);
				return;
			}
			catch(Exception e1)
			{
				System.out.println(e1.getMessage());
			}
			
		}
	}
}