将图片转成二进制并生成Base64编码字符串,再将二进制转换成各种图片

import java.awt.image.BufferedImage;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;

import javax.imageio.ImageIO;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

public class TestImageBinary {
	static BASE64Encoder encoder = new sun.misc.BASE64Encoder();
	static BASE64Decoder decoder = new sun.misc.BASE64Decoder();
	
	public static void main(String[] args) {
		System.out.println(getImageBinary());
		
		base64StringToImage(getImageBinary());
	}
	
	static String getImageBinary(){
		File f = new File("c://20090709442.jpg");		
		BufferedImage bi;
		try {
			bi = ImageIO.read(f);
			ByteArrayOutputStream baos = new ByteArrayOutputStream();
			ImageIO.write(bi, "jpg", baos);
			byte[] bytes = baos.toByteArray();
			
			return encoder.encodeBuffer(bytes).trim();
		} catch (IOException e) {
			e.printStackTrace();
		}
		return null;
	}
	
	static void base64StringToImage(String base64String){
		try {
			byte[] bytes1 = decoder.decodeBuffer(base64String);
			
			ByteArrayInputStream bais = new ByteArrayInputStream(bytes1);
			BufferedImage bi1 =ImageIO.read(bais);
			File w2 = new File("c://QQ.bmp");//可以是jpg,png,gif格式
			ImageIO.write(bi1, "jpg", w2);//不管输出什么格式图片，此处不需改动
		} catch (IOException e) {
			e.printStackTrace();
		}
	}

}