三十八毒

包括图片的上传、保存、缩放等功能，有需要对图片进行处理时可直接COPY过去用，前段时间写的，懒的写注释，大家凑合看吧。

package net.resume.web.util;

import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.util.Iterator;

import javax.imageio.ImageIO;
import javax.imageio.ImageReader;
import javax.imageio.ImageWriter;
import javax.imageio.stream.ImageInputStream;
import javax.imageio.stream.ImageOutputStream;

public class ImageTools {
	
	public static final String PNG = "png";
	
	public static final String JPEG = "jpeg";
	
	public static final String JPG = "jpg";
	
	public static final String GIF = "gif";

	public ImageTools() {
		super();
	}
	
	public static BufferedImage thumbFilter(BufferedImage source, int width, int height){
		BufferedImage thumb = new BufferedImage(width,height,BufferedImage.TYPE_4BYTE_ABGR);
		
//		if(source.getWidth() / (double)width > source.getHeight() / (double)height){
//			height = (int)((double)width * source.getHeight()/source.getHeight() / source.getWidth());
//		}else{
//			width = (int)((double)height * source.getWidth() / source.getHeight());
//		}
		
		Graphics2D g = thumb.createGraphics();
		g.setColor(new Color(255,255,255,255));
		Image buf = source.getScaledInstance(width,height,Image.SCALE_SMOOTH);
		g.drawImage(buf,(thumb.getWidth() - width)/2,(thumb.getHeight() - height) / 2, null);
		
		return thumb;
	}
	
	public static BufferedImage readImage(InputStream in,String type)throws IOException{
		Iterator readers = ImageIO.getImageReadersByFormatName(type);
		ImageReader reader = (ImageReader)readers.next();
		
		ImageInputStream iis = ImageIO.createImageInputStream(in);
		
		reader.setInput(iis,true);
		
		BufferedImage img = reader.read(0);
		
		return img;
	}
	
	public static BufferedImage readImage(String fileName) throws IOException{
		String type = fileName.substring(fileName.lastIndexOf(".")+1);
		return readImage(new FileInputStream(fileName), type);
	}
	
	public static BufferedImage readImage(URL url) throws IOException{
		String type = url.toString().substring(url.toString().lastIndexOf(".")+1);
		return readImage(url.openStream(), type);
	}
	
	public static BufferedImage readImage(File file) throws IOException{
		String type = file.getName().substring(file.getName().lastIndexOf(".")+1);
		return readImage(new FileInputStream(file), type);
	}
	

	public static void writeImage(BufferedImage image,
			String filename) throws IOException {

		String type = filename.substring(filename.lastIndexOf(".")+1);
		writeImage(image, type, filename);
	}
	
	public static void writeImage(BufferedImage image, String type,
			String filename) throws IOException {
		File f = new File(filename);
		writeImage(image, type, f);
	}

	public static void writeImage(BufferedImage image, String type, File file)
			throws IOException {

		Iterator writers = ImageIO.getImageWritersByFormatName(type);
		ImageWriter writer = (ImageWriter) writers.next();

		//Once an ImageWriter has been obtained, its destination must be set to an ImageOutputStream:

		//File f = new File(filename);
		ImageOutputStream ios = ImageIO.createImageOutputStream(file);
		writer.setOutput(ios);

		//Finally, the image may be written to the output stream:

		writer.write(image);

	}

}