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How to GET image from url via API in java?

This should be an easy learning task but something went wrong:
Use API request to get image from some link and check it is in Base64 standard.
private static void getRequest() throws IOException {
URL url = new URL("http://apimeme.com/meme?meme=Alarm-Clock&top=Top+text&bottom=Bottom+text");
InputStream is = (InputStream) url.openStream();
FileInputStream imageInFile = new FileInputStream(is.toString());
byte imageData[] = new byte[2048];
imageInFile.read(imageData);
System.out.println(isBase64(imageInFile.toString()));
}
static boolean isBase64(String path) {
try {
Base64.getDecoder().decode(path);
return true;
} catch(IllegalArgumentException e) {
return false;
}
}
Right now problem is on line
InputStream is = (InputStream) url.openStream();
Server sends 403. How to fix this? Method isBase64 should work but the program doesn't reach this line.

Your need 3 header for avoid http 403 error code
private static void getRequest() throws IOException {
URL url = new URL("http://apimeme.com/meme?meme=Alarm-Clock&top=Top+text&bottom=Bottom+text");
URLConnection is = url.openConnection();
is.setRequestProperty("Host", "apimeme.com");
is.setRequestProperty("Cookie", "*");
is.setRequestProperty("User-Agent", "*");
byte[] imageData = new byte[2048];
File downloadFile = new File("download.png");
FileOutputStream outputStream = new FileOutputStream(downloadFile);
int read;
while ((read = is.getInputStream().read(imageData)) != -1) {
outputStream.write(imageData, 0, read);
}
outputStream.close();
System.out.println(isBase64(downloadFile.getAbsolutePath()));
}

403 is means that you do not have permission to view this URL. You cannot do anything to fix this client side, even authorization would not help (if the ressource required authorization, the server would send 401 instead). So to fix the issue, whoever is in charge of the web server delivering the URL you're trying to access will have to fix this - if they think you should have access.

Download file from website on Android's Chrome- Java

I'm trying to download an.APK on Android's Chrome from my Glassfish server, but all I got is a "zero kb" file.
On Windows(PC)'s Chrome and on Android's Firefox it works correctly.
I'm using the following code:
private void downloadAPK(HttpServletRequest request, HttpServletResponse response, PrintWriter out){
String file = "/usr/local/glassfish4/glassfish/domains/domain1/applications/foo/foo.apk";
FileInputStream inputStream = null;
try{
File downloadFile = new File(file);
inputStream = new FileInputStream(downloadFile);
response.setHeader("Content-Disposition","attachment;filename="+file.getName());
int c = 0;
while ((c = inputStream.read()) != -1)
out.write(c);
} catch (Exception e) {
// code
}
// closing code
}
There is something that I'm missing to make it work on Android's Chrome?

java applet HTTP download file can not work

i write simple applet to download file from HTTP URL.
In Eclipse or Netbeans, it 's work well and can download file to d://abc//123.iso on my HDD.
This is my code :
public class download {
public static void saveUrl(final String filename, final String urlString)
throws MalformedURLException, IOException {
BufferedInputStream in = null;
FileOutputStream fout = null;
try {
in = new BufferedInputStream(new URL(urlString).openStream());
fout = new FileOutputStream(filename,true);
final byte data[] = new byte[1024];
int count;
fout.write(data, 0, count);
} finally {
if (in != null) {
in.close();
}
if (fout != null) {
fout.close();
}
}
}
}
public class HelloWorldApplet extends Applet
{
public void paint (Graphics g)
{
g.drawString ("Download file", 25, 50);
String url ="http://downloads.asterisk.org/pub/telephony/asterisk-now/AsteriskNOW-612-current-32.iso";
String file_out = "d:\\abc\\123.iso";
download.saveUrl(file_out, url);
}
}
==========================
But when export to jar file and run with html, browser can creat new file 123.iso on my HDD but the size of this file is always 2 Kbps. i think it do not download anything.
Please help me
Thanks so much
P/s : i try to sign jar file with jarsigner but it does not solve the problem

Although I'm skeptical as to the code above doing anything at all as posted, if even compiling, here's the solution I use for doing automatic update downloads of large (>100 MB) files:
HttpGet httpGet;
RequestConfig requestConfig;
getProxySettings();
//Check to see if there is a proxy availabble.
if (!LicensePreloader.proxyAddr.equals("")) {
requestConfig = RequestConfig.custom()
.setSocketTimeout(5000)
.setConnectTimeout(5000)
.setConnectionRequestTimeout(5000)
.setProxy(new HttpHost(LicensePreloader.proxyAddr, LicensePreloader.proxyPort))
.build();
} else {
//No proxy was available, just use regular internet.
requestConfig = RequestConfig.custom()
.setSocketTimeout(5000)
.setConnectTimeout(5000)
.setConnectionRequestTimeout(5000)
.build();
}
httpGet = new HttpGet(this.remoteUrl);
HttpResponse response;
InputStream remoteContentStream = null;
OutputStream localFileStream = null;
try {
httpGet.setConfig(requestConfig);
response = httpClient.execute(httpGet);
//This builds the content of our file we're downloading.
remoteContentStream = response.getEntity().getContent();
long fileSize = response.getEntity().getContentLength();
File dir = localFile.getParentFile();
dir.mkdirs();
localFileStream = new FileOutputStream(localFile);
//Set the buffer, in our use case, it's always the deafult 8192 bytes.
byte[] buffer = new byte[bufferSize];
int sizeOfChunk;
int amountComplete = 0;
//Simply loop through and download the file in 'chunks'
while ((sizeOfChunk = remoteContentStream.read(buffer)) != -1) {
localFileStream.write(buffer, 0, sizeOfChunk);
amountComplete += sizeOfChunk;
updateProgress(amountComplete, fileSize);
}
return localFile;
} finally {
//Make sure to clean everything up.
try {
if (remoteContentStream != null) {
remoteContentStream.close();
}
if (localFileStream != null) {
localFileStream.close();
}
} catch (IOException ex) {
//If we're here, it's likely because the internet conneciton
//couldn't be established, or it was cut short in the middle.
ex.printStackTrace(System.out);
failed();
}
}
}
This is obviously overkill for your application, and you can probably just forget all the proxy business, but I kept it in there for completeness sake. There are a couple helper methods I didn't include, but again, they're almost all exclusively for proxy handling.
good luck!

You are writing one the first read in the input. You need to write the file until the input is empty.
Try this while in you code
while ((count = in.read(data)) != -1) {
fout.write(data, 0, count);
...
}

Download multiple files Java

I am using the following code to download a file within the WEB-INF
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
String b = null;
Cookie[] cookies = request.getCookies();
if (cookies != null) {
for (Cookie cookie : cookies) {
if (cookie.getName().equals("thecookie")) {
b = cookie.getValue();
}
}
}
BufferedReader br = new BufferedReader(new FileReader(b+"/logs.txt"));
String path = br.readLine();
br.close();
File file = new File(path+"/Results.xlsx");
FileInputStream fileIn = new FileInputStream(file);
ServletOutputStream out = response.getOutputStream();
response.setHeader("Content-Disposition", "attachment; filename=Result.xlsx");
response.setContentType(
"application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
byte[] outputByte = new byte[4096];
int bytesRead;
//copy binary contect to output stream
while((bytesRead = fileIn.read(outputByte)) != -1)
{
out.write(outputByte, 0, bytesRead);
}
fileIn.close();
out.flush();
out.close();
}
along with this I want to download another file at the same location Results.csv I've tried using the same code above twice but it didn't work.
How to download multiple files without using zipoutputstream?

MIME/multipart responses are, as far as I know, not part of the HTTP standard. Some browsers seem to support it, but I recommend against using it.
Instead, you could pack those files into a ZIP file (using a ZipOutputStream), and return that as your response. That's also the way DropBox handles the download of multiple files at once.

It is possible but having them in separate requests if you plan to work within every browser.
Here a sample script for downloading a file via javascript
function downloadFile(url, name) {
var link = document.createElement("a");
link.download = name;
link.href = url;
document.body.appendChild(link);
link.click();
document.body.removeChild(link);
delete link;
}
downloadFile(url1,filenam1);
downloadFile(url2,filenam2);
downloadFile(url3,filenam3);
...

Sending file from client to server and do not lost connection, is it possible?

I would like to send file from client to server and be able do it again in the future.
So my client connect to server and upload file, ok - it works but it hangs at the end..
so here is my code in client, the server side is quite similar.
private void SenderFile(File file) {
try {
FileInputStream fis = new FileInputStream(file);
OutputStream os = socket.getOutputStream();
IoUtil.copy(fis, os);
} catch (Exception ex) {
ex.printStackTrace();
}
}
IoUtils found on Stack :)
public static class IoUtil {
private final static int bufferSize = 8192;
public static void copy(InputStream in, OutputStream out)
throws IOException {
byte[] buffer = new byte[bufferSize];
int read;
while ((read = in.read(buffer, 0, bufferSize)) != -1) {
out.write(buffer, 0, read);
}
out.flush();
}
}
Explanation: my client has a socket connected to server, and I send any file to him.
My server download it but hangs at the end because he is listening for more infromation.
If I choose another file, my server will download new data to the existing one.
How could I upload any file to server, make my server work on and be able download another one file properly?
ps. If I add to ioutil.copy at the end of function out.close my server will work on but the connection will be lost. I do not know what to do :{
After update:
Client side:
private void SenderFile(File file) {
try {
FileInputStream fis = new FileInputStream(file);
OutputStream os = socket.getOutputStream();
DataOutputStream wrapper = new DataOutputStream(os);
wrapper.writeLong(file.length());
IoUtil.copy(fis, wrapper);
} catch (Exception ex) {
ex.printStackTrace();
}
}
Server side (thread listening for any message from client):
public void run() {
String msg;
File newfile;
try {
//Nothing special code here
while ((msg = reader.readLine()) != null) {
String[] message = msg.split("\\|");
if (message[0].equals("file")) {//file|filename|size
String filename = message[1];
//int filesize = Integer.parseInt(message[2]);
newfile = new File("server" + filename);
InputStream is = socket.getInputStream();
OutputStream os = new FileOutputStream(newfile);
DataInputStream wrapper = new DataInputStream(is);
long fileSize = wrapper.readLong();
byte[] fileData = new byte[(int) fileSize];
is.read(fileData, 0, (int) fileSize);
os.write(fileData, 0, (int) fileSize);
System.out.println("Downloaded file");
} else
//Nothing special here too
}
} catch (Exception ex) {
ex.printStackTrace();
}
}
Ok, now I can download file - still once, another one is downloaded but unable to read. For example, second time I want send by client a file.png. I got it on server, but this file is not possible to view.
Thanks in advance :)

You need to make your server able to differentiate files. The easiest way is to tell in advance how many bytes the receiving end should expect for a single file; this way, it knows when to stop reading and wait for another one.
This is what the SenderFile method could look like:
private void SenderFile(File file)
{
try
{
FileInputStream fis = new FileInputStream(file);
OutputStream os = socket.getOutputStream();
DataOutputStream wrapper = new DataOutputStream(os);
wrapper.writeLong(file.length());
IoUtil.copy(fis, wrapper);
}
catch (Exception ex)
{
ex.printStackTrace();
}
}
And this is what the ReceiveFile method could look like:
// the signature of the method is complete speculation, adapt it to your needs
private void ReceiveFile(File file)
{
FileOutputStream fos = new File(file);
InputStream is = socket.getInputStream();
DataInputStream wrapper = new DataInputStream(is);
// will not work for very big files, adapt to your needs too
long fileSize = wrapper.readLong();
byte[] fileData = new byte[fileSize];
is.read(fileData, 0, fileSize);
fos.write(fileData, 0, fileSize);
}
Then don't close the socket.