报错javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import java.util.Iterator;

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


public class TestDownLoadImage {
	
	public static void main(String[] args) {
		 String url="http://wx1.sinaimg.cn/mw690/006sl6kBgy1fel3aq0nyej30i20hxq7i.jpg";
		 String downToFilePath="d:/download/image/";
		 String fileName="test";
		 imageDownLoad(url, downToFilePath,fileName);
		
	}
	public static void  imageDownLoad(String urlString, String filepath,String filename) {
		
		InputStream is =null;
		ImageInputStream iis=null;
		OutputStream os =null;
		String downloadPath=null;
	    try {
	    	
			URL url = new URL(urlString);
			URLConnection con = url.openConnection();
			is = con.getInputStream();
			iis=ImageIO.createImageInputStream(is);
			Iterator<ImageReader> iter = ImageIO.getImageReaders(iis);  
			if (!iter.hasNext()) {  
                return  ;  
            }  
            ImageReader reader = iter.next();  
             //读文件格式jpg 等
            String imgFormat=reader.getFormatName();  
			byte[] bs = new byte[1024];
			int len;
			File file=new File(filepath);
			if(!file.exists()){			
				file.mkdir();
			}
			downloadPath=filepath+"//"+filename+"."+imgFormat;