Download file (images in particular) from http url

  
  
//------------------------------------------------------------//   
//  DownloadURL.java:                                         //   
//------------------------------------------------------------//   
//  A Java program that demonstrates a procedure that can be  //   
//  used to download the contents of a specified URL          //  
//  (Image in this case). Takes File name (containg URL list) as input.                                     //   
//------------------------------------------------------------//   
  
  
import java.io.*;   
import java.net.*;   
import java.io.File;  
import java.util.*;  
  
public class DownloadURL {   
  
	  
	//-----------------------------------------------------//   
	//    Execute: java DownloadURL UrlListFile.txt        //  
	//-----------------------------------------------------//   
	public static void main (String[] args)   
	{   
		DownloadURL dnlUrl = new DownloadURL();  
		  
		String fileName = "";  
		try  
		{  
			fileName = args[0];  
		}  
		catch(Exception e)  
		{  
			System.out.println("Url File name not specified : " + e);  
			System.exit(0);  
		}  
  
		long startTime=System.currentTimeMillis();  
  
		dnlUrl.GetUrlContents(fileName);  
  
		long endTime=System.currentTimeMillis();  
		float execTime = (((float)(endTime - startTime) / 1000) / 60);  
		System.out.println("\n\nTime taken for Execution = " + execTime + " min\n\t\tOR\nTime taken for Execution = "  + (execTime / 60) + " hr");  
		  
	}  // end of main   
	  
	public static void GetUrlContents(String fileName)  
	{  
		//-----------------------------------------------------//   
		//       Start creating a few objects needed.          //  
		//-----------------------------------------------------//   
  
		URL url;   
		InputStream is = null;   
		String strOutFileName = "", strUrl = "";  
		  
		FileOutputStream out = null; 			// declare a file output object  
		PrintStream p = null; 					// declare a print stream object  
	  
		try  
		{  
			int urlCounter = 0;  
			BufferedReader in = new BufferedReader(new FileReader(fileName));  
			while((strUrl = in.readLine()) != null)  
			{  
  
				try   
				{   
					url = new URL(strUrl);   
					  
					is = url.openStream();         // throws an IOException   
					  
					try  
					{  
						strOutFileName = strUrl.substring(strUrl.lastIndexOf("/") + 1);  
						System.out.print("\n" + ++urlCounter + " : " + strOutFileName);  
						out = new FileOutputStream("./images/" + strOutFileName);  
						p = new PrintStream( out );  
					}  
					catch(Exception e)  
					{  
						 System.out.println("Error in file handling (create) : " + e);  
					}  
  
					BufferedInputStream bis=new BufferedInputStream(is);  
					BufferedOutputStream bos=new BufferedOutputStream(out);  
					byte[] buff = new byte[2048];  
					int bytesRead;  
  
					System.out.print(" : Downloading");  
					while(-1 != (bytesRead = bis.read(buff, 0, buff.length)))   
					{  
						System.out.print(".");  
						bos.write(buff, 0, bytesRead);  
						bos.flush();						  
					}  
					System.out.print("done");  
					bis.close();  
					bos.close();  
				}   
				catch (MalformedURLException mue)   
				{  
					System.out.println("Ouch - a MalformedURLException happened.");   
					mue.printStackTrace();   
					System.exit(1);   
				}   
				catch (IOException ioe)   
				{   
					System.out.println("Oops- an IOException happened.");   
					ioe.printStackTrace();   
					System.exit(1);  
				}   
				catch (Exception e)   
				{   
					System.out.println("Exception happened : " + e);   
					e.printStackTrace();   
					System.exit(1);  
				}   
				finally   
				{   
					 //---------------------------------//   
					 //          Close the InputStream  //   
					 //---------------------------------//   
					try   
					{   
						is.close();   
					}   
					catch (IOException ioe)   
					{   
						// just going to ignore this one   
					}   
				} // end of 'finally' clause   
			}	// end of while  
		}  
		catch(Exception exp)  
		{  
			System.out.println("Error in File reading : " + exp);  
		}  
	}	  
} // end of class definition