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How to retrieve a Long from Oracle using java

I have a database where a Long datatype has an image stored in it,
I want to retrieve it and write it to an image file,
I tried using getBytes method and write a file using for and it return as corrupt image,
I also tried using getBinarystream and write using fos I wrote it in an image file I get same corrupt error.
Code:
InputStream is = RS.getBinaryStream(1);
FileOutputStream fos = new FileOutputStream ("image.bmp");
Int c;
While((c=is.read())!=-1)
{
fos.write(c);
}
fos.close;

To store binary data you should use LONG_RAW or a BLOB. The type LONG is for character based (text) data.

How to convert InputStream to a PDF in Java, without damaging the file?

I have an InputStream which I would like to convert to a PDF, and save that PDF in a directory. Currently, my code is able to convert the InputStream to a PDF and the PDF does show up in the correct directory. However, when I try to open it, the file is damaged.
Here is the current code:
InputStream pAdESStream = signingServiceConnector.getDirectClient().getPAdES(this.statusReader.getStatusResponse().getpAdESUrl());
byte[] buffer = new byte[pAdESStream.available()];
pAdESStream.read(buffer);
File targetFile = new File(System.getProperty("user.dir") + "targetFile2.pdf");
OutputStream outStream = new FileOutputStream(targetFile);
outStream.write(buffer);
Originally, the InputStream was a pAdES-file (https://en.wikipedia.org/wiki/PAdES). However, it should be able to be read as just a regular PDF.
Does anyone know how to convert the InputStream to a PDF, without getting a damaged PDF as a result?

Hello it might be a bit late but you can use PDFBOX api (or itextpdf)
https://www.tutorialkart.com/pdfbox/create-write-text-pdf-file-using-pdfbox/
here is a tuto of the process gl

How to write encoded text to a file using Java?

How to write encoded text to a file using java/jsp with FileWriter?
FileWriter testfilewriter = new FileWriter(testfile, true);
testfilewriter.write(testtext);
testtext:- is text
testfile:- is String (Encoded)
What I m trying to do is encoding testfile with Base64 and storing it in file. What is the best way to do so?

Since your data is not plain text, you can't use FileWriter. What you need is FileOutputStream.
Encode your text as Base64:
byte[] encodedText = Base64.encodeBase64( testtext.getBytes("UTF-8") );
and write to file:
try (OutputStream stream = new FileOutputStream(testfile)) {
stream.write(encodedText);
}
or if you don't want to lose existing data, write in append mode by setting append boolean to true:
try (OutputStream stream = new FileOutputStream(testfile, true)) {
stream.write(encodedText);
}

You can do the encoding yourself and then write to the file as suggested by #Alper OR if you want to create a stream which does encoding/decoding to while writing and reading from file , apache commons codec library will come in handy see Base64OutputStream and Base64InputStream
Interestingly Java 8 has a similar API Base64.Encoder. Checkout the wrap method
Hope this helps.

The Approach to be followed depends on the algorithm you are using and writing the encoded file is same as writing the file in java
IMHO, if you are trying to do it using jsp , Kindly go with servlets .As jsp are not meant for business layers rather do servlets.

I'm not going to give the code, as it is pretty easy if you try it. I'll share the best way to do it as a psuedo code. Here are steps to write your encoded text.
Open input file in read mode & output file in append mode.
If input file isn't huge (it can fit in memory) then read whole file at once, otherwise read line-by-line.
Encode the text retrieved from file using Base64Encoder
Write in the output file in append mode.

You can't use a FileWriter directly for this task.
You asked how you can do it, but you didn't give any information about which JDK and library you use, so here are a few solutions with the standard tools.
If you're using Java 8:
String testFile = "";
try (Writer writer = new OutputStreamWriter(
Base64.getEncoder().wrap(
java.nio.file.Files.newOutputStream(
Paths.get(testFile),
StandardOpenOption.APPEND)),
StandardCharsets.UTF_8)
) {
writer.write("text to be encoded in Base64");
}
If you're using Java 7 with Guava:
String testFile = "";
CharSink sink = BaseEncoding.base64()
.encodingSink(
com.google.common.io.Files.asCharSink(
new File(testFile),
StandardCharsets.UTF_8,
FileWriteMode.APPEND))
.asCharSink(StandardCharsets.UTF_8);
try (Writer writer = sink.openStream()) {
writer.write("text to be encoded in Base64");
}
If you're using Java 6 with Guava:
String testFile = "";
CharSink sink = BaseEncoding.base64()
.encodingSink(
com.google.common.io.Files.asCharSink(
new File(testFile),
Charsets.UTF_8,
FileWriteMode.APPEND))
.asCharSink(Charsets.UTF_8);
Closer closer = Closer.create();
try {
Writer writer = closer.register(sink.openStream());
writer.write("text to be encoded in Base64");
} catch (Throwable e) { // must catch Throwable
throw closer.rethrow(e);
} finally {
closer.close();
}
I don't have much knowledge about other libraries so I won't pretend I do and add another helper.

Read hidden zip file

I have a jpeg, and on the end of it I wrote a zip file.
Inside this zip file is a single txt file called hidden.txt. I can change the extension to zip and read the file just fine on my laptop (debian) but when I try to read it using either a ZipInputStream or using ZipFile I get an error telling me it's not a zip file.
I tried separating the jpg part out first by reading the whole thing to a Bitmap then writing that to a byte[], however the byte[] encompassed more than just the image.
My method to combine the bitmap and the zipFile (a byte[])
private byte[] combineFiles(Bitmap drawn, byte[] zip) throws
IOException {
InputStream in;
ByteArrayOutputStream out = new ByteArrayOutputStream();
/*write the first file*/
byte[] img;
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
drawn.compress(Bitmap.CompressFormat.JPEG, 100, byteArrayOutputStream);
img = byteArrayOutputStream.toByteArray();
in = new ByteArrayInputStream(img);
IOUtils.copy(in, out);
in.close();
/*add the second (hidden) file*/
in = new ByteArrayInputStream(zip);
IOUtils.copy(in, out);
out.flush();
in.close();
return out.toByteArray();
}
So really I have two questions,
How do I separate the jpg and zip portions of the file?
How do I unzip hidden.txt (preferably into a byte[])
fairly certain I know this one, but what I am doing currently does not work, probably because I am doing #1 wrong

Ok, well here's how I would do this. Although it's very hacky.
The problem is that it's hard to tell the index of the boundary between the image data and the zip data. Assuming that you can write arbitrary data after the image data and still have a working image file, here is something you could try:
write out the image data.
write out a magical string like "BEGIN_ZIP"
write out the zip data.
Now, when you are trying to read things back in:
byte[] data = readAllTheBytes();
int index = searchFor("BEGIN_ZIP", data) + "BEGIN_ZIP".length();
// now you know that the zip data begins at index and goes to the end of the byte array
// so just use a regular zipinputstream to read in the zip data.

In JPEG file 0xFF, 0xD8 sequence of bytes indicates start of image and 0xFF, 0xD9 sequence of bytes indicates end of image JPEG Structure Wikipedia. So simply search for the latter sequence in file and you will be able to separate image and zip parts. Then use ZipInputStream to read (decompress) the data from zip file.

Commons Net FTPClient retrieved file encoding issue

I'm retrieving a file from a FTP Server. The file is encoded as UTF-8
ftpClient.connect(props.getFtpHost(), props.getFtpPort());
ftpClient.login(props.getUsername(), props.getPassword());
ftpClient.setFileType(FTP.BINARY_FILE_TYPE);
inputStream = ftpClient.retrieveFileStream(fileNameBuilder
.toString());
And then somewhere else I'm reading the input stream
bufferedReader = new BufferedReader(new InputStreamReader(
inputStream, "UTF-8"));
But the file is not getting read as UTF-8 Encoded!
I tried ftpClient.setAutodetectUTF8(true); but still doesn't work.
Any ideas?
EDIT:
For example a row in the original file is
...00248090041KENAN SARÐIN 00000000015.993FAC...
After downloading it through FTPClient, I parse it and load in a java object, one of the fields of the java object is name, which for this row is read as "KENAN SAR�IN"
I tried dumping to disk directly:
File file = new File("D:/testencoding/downloaded-file.txt");
FileOutputStream fop = new FileOutputStream(file);
ftpClient.retrieveFile(fileName, fop);
if (!file.exists()) {
file.createNewFile();
}
I compared the MD5 Checksums of the two files(FTP Server one and the and the one dumped to disk), and they're the same.

I would separate out the problems first: dump the file to disk, and compare it with the original. If it's the same as the original, the problem has nothing to do with UTF-8. The FTP code looks okay though, and if you're saying you want the raw binary data, I'd expect it not to mess with anything.
If the file is the same after transfer as before, then the problem has nothing to do with FTP. You say "the file is not getting read as UTF-8 Encoded" but it's not clear what you mean. How certain are you that it's UTF-8 text to start with? If you could edit your question with the binary data, how it's being read as text, and how you'd expect it to be read as text, that would really help.

Try to download the file content as bytes and not as characters using InputStream and OutputStream instead of InputStreamReader. This way you are sure that the file is not changed during transfer.