java通过url读取网络图片

使用java.net读取网络文件

import java.io.BufferedInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.net.HttpURLConnection;
 import java.net.URL;  

 public class downimage {  

 public void saveToFile(String destUrl) {
 FileOutputStream fos = null;
 BufferedInputStream bis = null;
 HttpURLConnection httpUrl = null;
 URL url = null;
 int BUFFER_SIZE = 1024;
 byte[] buf = new byte[BUFFER_SIZE];
 int size = 0;
 try {
 url = new URL(destUrl);
 httpUrl = (HttpURLConnection) url.openConnection();
 httpUrl.connect();
 bis = new BufferedInputStream(httpUrl.getInputStream());
 fos = new FileOutputStream("c:\\haha.gif");
 while ((size = bis.read(buf)) != -1) {
 fos.write(buf, 0, size);
 }
 fos.flush();
 } catch (IOException e) {
 } catch (ClassCastException e) {
 } finally {
 try {
 fos.close();
 bis.close();
 httpUrl.disconnect();
 } catch (IOException e) {
 } catch (NullPointerException e) {
 }
 }
 }
 public static void main(String[] args) {
 // TODO Auto-generated method stub  

 downimage dw=new downimage();
 dw.saveToFile("http://10.81.36.193:8081/png.png");
 }
 }  

注意：

　　如果路径或者源文件名称中包含特殊符号或者空格，会报505错误，此时需要对URL进行转码

　　

　　ftpUrl=ftpUrl.replaceAll("%", "%25");//先将地址本身带有的%转为%25
　　ftpUrl=ftpUrl.replaceAll(" ", "%20");//再将空格转换为%20

转码之后读取正常。