java 上传图片

1 菜单图片jpg存储大小最小，一般尺寸160*120，或者210*158。指定大小，压缩存储，每张8kb内

 1     public static void main(String[] args) throws Exception {
 2         File oldFile = new File("e:/白菜肉片炖粉条.png");  
 3         try {      
 4             Image srcFile = ImageIO.read(oldFile);    
 5             String srcImgPath = "e:/白菜肉片炖粉条7.png";  //存成jpg格式
 6             //BufferedImage buffImg = new BufferedImage(160, 120, BufferedImage.TYPE_INT_ARGB);  
 7             BufferedImage buffImg = new BufferedImage(160, 120, BufferedImage.TYPE_INT_RGB);  
 8             Graphics2D graphics = buffImg.createGraphics();  
 9             graphics.setBackground(new Color(255,255,255));  
10             graphics.setColor(new Color(255,255,255));  
11             graphics.fillRect(0, 0, 160, 120);  
12             graphics.drawImage(srcFile.getScaledInstance(160, 120, Image.SCALE_SMOOTH), 0, 0, null);    
13             ImageIO.write(buffImg, "jpg", new File(srcImgPath));    
14         } catch (Exception e) {    
15             e.printStackTrace();    
16         } 
17     }

2 读取文件夹中图片

 1     public static void main(String[] args) throws Exception {
 2         String URL="f:/xx/";//URL为文件夹目录
 3         File file=new File(URL);  
 4         if (file.isDirectory()){//判断file是否是文件目录 若是返回TRUE  
 5             String name[]=file.list();//name存储file文件夹中的文件名  
 6             for (int i=0; i<name.length; i++){  
 7                 File oldFile=new File(URL, name[i]);//此时就可得到文件夹中的文件                 
 8                 System.out.println(name[i]);//五色金针菇.png 京酱肉丝.png
 9                 // oldFile.delete();//删除文件  
10             }  
11         }  
12     }

3 二合一

 1     public static void main(String[] args) throws Exception {
 2         String oldUrl="f:/xx/";//文件源
 3         String newUrl="f:/png/";//存储文件夹
 4         File f2=new File(newUrl);
 5         if(!f2.exists()){
 6             f2.mkdir();//如果目录不存在，新建
 7         }
 8         File file=new File(oldUrl);  
 9         if(!file.exists()){
10             throw new Exception("文件不存在！");
11         }
12         /*BufferedImage bi1 = ImageIO.read(file);
13         if(bi1 == null){ 
14             System.out.println("此文件不为图片文件");
15         }*/
16         if (file.isDirectory()){//判断file是否是文件目录 若是返回TRUE  
17             String name[]=file.list();//name存储file文件夹中的文件名  
18             for (int i=0; i<name.length; i++){  
19                 File oldFile=new File(oldUrl, name[i]);//此时就可得到文件夹中的文件                 
20                 System.out.println(name[i]);//五色金针菇.png 京酱肉丝.png
21                 Image srcFile = ImageIO.read(oldFile);    
22                 String srcImgPath = newUrl+name[i].split("[.]")[0]+".png";  //存成jpg格式
23                 //BufferedImage buffImg = new BufferedImage(160, 120, BufferedImage.TYPE_INT_ARGB);  
24                 BufferedImage buffImg = new BufferedImage(160, 120, BufferedImage.TYPE_INT_RGB);  
25                 Graphics2D graphics = buffImg.createGraphics();  
26                 graphics.setBackground(new Color(255,255,255));  
27                 graphics.setColor(new Color(255,255,255));  
28                 graphics.fillRect(0, 0, 160, 120);  
29                 graphics.drawImage(srcFile.getScaledInstance(160, 120, Image.SCALE_SMOOTH), 0, 0, null);    
30                 ImageIO.write(buffImg, "jpg", new File(srcImgPath));   
31             }  
32         }  
33     }

4 读text文件（1句柄file 2 in 3 ib ）

截图http://blog.csdn.net/lql876381722/article/details/2203512

	public static void main(String[] args) throws IOException {
		File f1 = new File("e:/a.jpg");
		FileInputStream is = new FileInputStream(f1); 
		//获取图片流 
		ImageInputStream iis = ImageIO.createImageInputStream(is);
		System.out.println(f1);
		Iterator<ImageReader> it = ImageIO.getImageReadersByFormatName("jpg");  
        ImageReader reader = it.next();
        reader.setInput(iis,true) ;        
		  ImageReadParam param = reader.getDefaultReadParam(); 
		  Rectangle rect = new Rectangle(0,0,100,100); 
		  param.setSourceRegion(rect); 
		  BufferedImage bi = reader.read(0,param);  
		  ImageIO.write(bi, "jpg", new File("e:/te.jpg"));  
	}