I have got links like this link, which directly ask for the filename to save with, and start downloading in the browser.
How can I download or save this file programmatically?
I tried with the following method:
static void DownloadFile(String url, String fileName) throws MalformedURLException, IOException
{
url = "http://dbpedia.org/sparql?default-graph-uri=http%3A%2F%2Fdbpedia.org&query=DESCRIBE+<"+ url +">&format=text%2Fcsv";
URL link = new URL(url); //The file that you want to download
InputStream in = new BufferedInputStream(link.openStream());
ByteArrayOutputStream out = new ByteArrayOutputStream();
byte[] buf = new byte[1024];
int n = 0;
while (-1!=(n=in.read(buf)))
{
out.write(buf, 0, n);
}
out.close();
in.close();
byte[] response = out.toByteArray();
FileOutputStream fos = new FileOutputStream(fileName);
fos.write(response);
fos.close();
System.out.println("Finished");
}
but this save the file having only the first line as ""subject","predicate","object"
" and not the complete file.
EDIT:
As suggested in an answer I tried the following, but that too gave only the first line of the file:
static void DownloadFile(String s_url, String fileName) throws MalformedURLException, IOException
{
s_url = "http://dbpedia.org/sparql?default-graph-uri=http%3A%2F%2Fdbpedia.org&query=DESCRIBE+<"+ s_url +">&format=text%2Fcsv";
//url = "http://dbpedia.org/data/Sachin_Tendulkar.rdf";
try {
URL url = new URL(s_url); //The file that you want to download
// read text returned by server
BufferedReader in = new BufferedReader(new InputStreamReader(url.openStream()));
PrintWriter out = new PrintWriter(fileName);
String line;
while ((line = in.readLine()) != null) {
out.println(line);
}
in.close();
out.close();
}
catch (MalformedURLException e) {
System.out.println("Malformed URL: " + e.getMessage());
}
catch (IOException e) {
System.out.println("I/O Error: " + e.getMessage());
}
System.out.println("Finished");
}
EDIT:
I tried with Apache FileUtils too, but that too gave only the first line of the file.
static void DownloadFile(String s_url, String fileName) throws MalformedURLException, IOException
{
s_url = "http://dbpedia.org/sparql?default-graph-uri=http%3A%2F%2Fdbpedia.org&query=DESCRIBE+<"+ s_url +">&format=text%2Fcsv";
URL url = new URL(s_url); //The file that you want to download
FileUtils.copyURLToFile(url, new File(fileName));
System.out.println("Finished");
}
if you want to download a file, Apache Commons have just what you are looking for, works great!
org.apache.commons.io.FileUtils.copyURLToFile(new URL("URL")), new File("path/to/file"));
if the url returns text, you can try something like this:
try {
URL url = new URL("http://www.google.com:80/");
// read text returned by server
BufferedReader in = new BufferedReader(new InputStreamReader(url.openStream()));
PrintWriter out = new PrintWriter("filename.txt");
String line;
while ((line = in.readLine()) != null) {
out.println(line);
}
in.close();
out.close();
}
catch (MalformedURLException e) {
System.out.println("Malformed URL: " + e.getMessage());
}
catch (IOException e) {
System.out.println("I/O Error: " + e.getMessage());
}
Related
So I followed some of the advices for this exception online, including:
Not to create files directly under the root directory of external
storage;
Add write and read permissions to the manifest;
Change my numeric file names to non-numeric.
User FileInputStream when reading.
However I still see this exception being thrown:
java.io.FileNotFoundException, open failed: ENOENT
Here is my class:
public class SaveReminderToFile {
private String fileName;
private File gFile;
public SaveReminderToFile(String fileName) throws FileNotFoundException, UnsupportedEncodingException {
this.fileName = "reminder"+fileName+".txt";
File root = android.os.Environment.getExternalStorageDirectory();
File dir = new File(root.getAbsolutePath()+"/ReminderApp2");
if (!dir.exists()){
dir.mkdirs();//create folders where write files
}
gFile = new File(dir,this.fileName);
}
public void writeToFile(String[] data, Context context){
try{
BufferedWriter oFile = new BufferedWriter(new OutputStreamWriter(
new FileOutputStream(gFile.getAbsoluteFile()), "UTF-8"));
for(String word :data) {
oFile.write(word);
oFile.newLine();
}
oFile.close();
}catch(IOException e){
Log.e("Exception",e.getMessage());
}
}
public String readFromFile(){
String ret="";
try{
FileInputStream inputStream =new FileInputStream(gFile.getAbsolutePath());
if ( inputStream != null ) {
InputStreamReader inputStreamReader = new InputStreamReader(inputStream);
BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
String receiveString = "";
StringBuilder stringBuilder = new StringBuilder();
while ( (receiveString = bufferedReader.readLine()) != null ) {
stringBuilder.append(receiveString);
}
inputStream.close();
ret = stringBuilder.toString();
}
} catch (FileNotFoundException e) {
Log.e("login activity", "File not found: " + e.toString());
ret=e.toString();
} catch (IOException e) {
Log.e("login activity", "Can not read file: " + e.toString());
ret=e.toString();
}
return ret;
}
}
I'm making a project where using java I / O
I have a file with the following data:
170631|0645| |002014 | 0713056699|000000278500
155414|0606| |002014 | 0913042385|000001220000
000002|0000|0000|00000000000|0000000000000000|000000299512
and the output I want is as follows:
170631
0645
002014
file so that the data will be decreased down
and this is my source code:
public class Tes {
public static void main(String[] args) throws IOException{
File file;
BufferedReader br =null;
FileOutputStream fop = null;
try {
String content = "";
String s;
file = new File("E:/split/OUT/Berhasil.RPT");
fop = new FileOutputStream(file);
br = new BufferedReader(new FileReader("E:/split/11072014/01434.RPT"));
if (!file.exists()) {
file.createNewFile();
}
while ((s = br.readLine()) != null ) {
for (String retVal : s.split("\\|")) {
String data = content.concat(retVal);
System.out.println(data.trim());
byte[] buffer = data.getBytes();
fop.write(buffer);
fop.flush();
fop.close();
}
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
I want is to generate output as above from the data that has been entered
File Input -> Split -> File Output
thanks :)
I think you forgot to mention what problem are you facing. Just by looking at the code it seems like you are closing the fop(FileOutputStream) every time you are looping while writing the split line. The outputStream should be closed once you have written everything, outside the while loop.
import java.io.*;
public class FileReadWrite {
public static void main(String[] args) {
try {
FileReader inputFileReader = new FileReader(new File("E:/split/11072014/01434.RPT"));
FileWriter outputFileWriter = new FileWriter(new File("E:/split/11072014/Berhasil.RPT"));
BufferedReader bufferedReader = new BufferedReader(inputFileReader);
BufferedWriter bufferedWriter = new BufferedWriter(outputFileWriter);
String line;
while ((line = bufferedReader.readLine()) != null) {
for (String splitItem : line.split("|")) {
bufferedWriter.write(splitItem + "\n");
}
}
bufferedWriter.flush();
bufferedWriter.close();
bufferedReader.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}
I just try to post data to google by using the following code,but always got 405 error,can anybody tell me way?
package com.tom.labs;
import java.net.*;
import java.io.*;
public class JavaHttp {
public static void main(String[] args) throws Exception {
File data = new File("D:\\in.txt");
File result = new File("D:\\out.txt");
FileOutputStream out = new FileOutputStream(result);
OutputStreamWriter writer = new OutputStreamWriter(out);
Reader reader = new InputStreamReader(new FileInputStream(data));
postData(reader,new URL("http://google.com"),writer);//Not working
//postData(reader,new URL("http://google.com/search"),writer);//Not working
sendGetRequest("http://google.com/search", "q=Hello");//Works properly
}
public static String sendGetRequest(String endpoint,
String requestParameters) {
String result = null;
if (endpoint.startsWith("http://")) {
// Send a GET request to the servlet
try {
// Send data
String urlStr = endpoint;
if (requestParameters != null && requestParameters.length() > 0) {
urlStr += "?" + requestParameters;
}
URL url = new URL(urlStr);
URLConnection conn = url.openConnection();
// Get the response
BufferedReader rd = new BufferedReader(new InputStreamReader(
conn.getInputStream()));
StringBuffer sb = new StringBuffer();
String line;
while ((line = rd.readLine()) != null) {
sb.append(line);
}
rd.close();
result = sb.toString();
} catch (Exception e) {
e.printStackTrace();
}
}
System.out.println(result);
return result;
}
/**
* Reads data from the data reader and posts it to a server via POST
* request. data - The data you want to send endpoint - The server's address
* output - writes the server's response to output
*
* #throws Exception
*/
public static void postData(Reader data, URL endpoint, Writer output)
throws Exception {
HttpURLConnection urlc = null;
try {
urlc = (HttpURLConnection) endpoint.openConnection();
try {
urlc.setRequestMethod("POST");
} catch (ProtocolException e) {
throw new Exception(
"Shouldn't happen: HttpURLConnection doesn't support POST??",
e);
}
urlc.setDoOutput(true);
urlc.setDoInput(true);
urlc.setUseCaches(false);
urlc.setAllowUserInteraction(false);
urlc.setRequestProperty("Content-type", "text/xml; charset=UTF-8");
OutputStream out = urlc.getOutputStream();
try {
Writer writer = new OutputStreamWriter(out, "UTF-8");
pipe(data, writer);
writer.close();
} catch (IOException e) {
throw new Exception("IOException while posting data", e);
} finally {
if (out != null)
out.close();
}
InputStream in = urlc.getInputStream();
try {
Reader reader = new InputStreamReader(in);
pipe(reader, output);
reader.close();
} catch (IOException e) {
throw new Exception("IOException while reading response", e);
} finally {
if (in != null)
in.close();
}
} catch (IOException e) {
e.printStackTrace();
throw new Exception("Connection error (is server running at "
+ endpoint + " ?): " + e);
} finally {
if (urlc != null)
urlc.disconnect();
}
}
/**
* Pipes everything from the reader to the writer via a buffer
*/
private static void pipe(Reader reader, Writer writer) throws IOException {
char[] buf = new char[1024];
int read = 0;
while ((read = reader.read(buf)) >= 0) {
writer.write(buf, 0, read);
}
writer.flush();
}
}
405 means "method not allowed". For example, if you try to POST to a URL that doesn't allow POST, then the server will return a 405 status.
What are you trying to do by making a POST request to Google? I suspect that Google's home page only allows GET, HEAD, and maybe OPTIONS.
Here's the body of a POST request to Google, containing Google's explanation.
405. That’s an error.
The request method POST is inappropriate for the URL /. That’s all we know.
Some PHP sites use a page to act as a middle man for handling file downloads.
With a browser this works transparently. There seems to a be a slight pause while the php page processes the request.
However, attempting a download through Java using a URL or HttpURLConnection returns a plain html page. How could I get the file downloads working in the same way?
Edit: Here is an example link:
http://depot.eice.be/index.php?annee_g=jour&cours=poo
Edit: Here is some of the code I've been testing:
// This returns an HTML page
private void downloadURL(String theURL) {
URL url;
InputStream is = null;
DataInputStream dis;
String s;
StringBuffer sb = new StringBuffer();
try {
url = new URL(theURL);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("GET");
conn.connect();
if (conn.getResponseCode()!=HttpURLConnection.HTTP_OK)
return;
InputStream in = conn.getInputStream();
ByteArrayOutputStream bos = new ByteArrayOutputStream();
int i;
while ((i = in.read()) != -1) {
bos.write(i);
}
byte[] b = bos.toByteArray();
FileOutputStream fos = new FileOutputStream( getNameFromUrl( theURL ) );
fos.write(b);
fos.close();
conn.disconnect();
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
// This will throw Exceptions if the URL isn't in the expected format
public String getNameFromUrl(String url) {
int slashIndex = url.lastIndexOf('/');
int dotIndex = url.lastIndexOf('.');
System.out.println("url:" + url + "," + slashIndex + "," + dotIndex);
if (dotIndex == -1) {
return url.substring(slashIndex + 1);
} else {
try {
return url.substring(slashIndex + 1, url.length());
} catch (StringIndexOutOfBoundsException e) {
return "";
}
}
}
Considering no other constrains, you can read the redirected URL from the HTTP header and connect to that URL directly from JAVA.
There is an API setting to follow redirects automatically – but it should be true by default. How do you access the URL?
See Java API docs...
I think I've found a solution using HttpUnit. The source of the framework is available if you wish to see how this is handled.
public void downloadURL(String url) throws IOException {
WebConversation wc = new WebConversation();
WebResponse indexResp = wc.getResource(new GetMethodWebRequest(url));
WebLink[] links = new WebLink[1];
try {
links = indexResp.getLinks();
} catch (SAXException ex) {
// Log
}
for (WebLink link : links) {
try {
link.click();
} catch (SAXException ex) {
// Log
}
WebResponse resp = wc.getCurrentPage();
String fileName = resp.getURL().getFile();
fileName = fileName.substring(fileName.lastIndexOf("/") + 1);
System.out.println("filename:" + fileName);
File file = new File(fileName);
BufferedInputStream bis = new BufferedInputStream(
resp.getInputStream());
BufferedOutputStream bos = new BufferedOutputStream(
new FileOutputStream(file.getName()));
int i;
while ((i = bis.read()) != -1) {
bos.write(i);
}
bis.close();
bos.close();
}
System.out.println("Done downloading.");
}
I have java code for file download through ftp, after download the file, it goes to default path. The specified destination path is not having the downloaded file. Why? my code is,
public class ftpUpload1
{
public static void main(String a[]) throws IOException
{
ftpUpload1 obj = new ftpUpload1();
URL url1 = new URL("ftp://vbalamurugan:vbalamurugan#192.168.6.38/ddd.txt" );
File dest = new File("D:/rvenkatesan/Software/ddd.txt");
obj.ftpDownload(dest, url1);
public void ftpDownload(File destination,URL url) throws IOException
{
BufferedInputStream bis = null;
BufferedOutputStream bos = null;
try
{
URLConnection urlc = url.openConnection();
bis = new BufferedInputStream( urlc.getInputStream() );
bos = new BufferedOutputStream( new
FileOutputStream(destination.getName() ) );
int i;
//read byte by byte until end of stream
while ((i = bis.read())!= -1)
{
// bos.write(i);
bos.write(i);
}
System.out.println("File Downloaded Successfully");
}
finally
{
if (bis != null)
try
{
bis.close();
}
catch (IOException ioe)
{
ioe.printStackTrace();
}
if (bos != null)
try
{
bos.close();
}
catch (IOException ioe)
{
ioe.printStackTrace();
}
}
}
}
}
The downloaded file "ddd.txt" not in the "D:/rvenktesan/Software". It is located in "D:rvenkatesan/JAVA PROJECTS". Why? guide me to store the file in specified path? Thanks in adcance.
You problem is FileOutputStream(destination.getName() ) );
change this to: FileOutputStream(destination.getAbsolutePath() ) );
getName wil return the filename "ddd.txt" only. I assume you are starting your app from D:/rvenkatesan/JAVA PROJECTS