Java Applet - Convert File to String

Question

How can convert a certain file into in a String? And then from that String to get the original file? This needs to realize it using Java.

It would be greate an example of code or a link to a tutorial.

Have to converted an entire File (not thecontent) in the String and then the String to the File.

Thanks.

why did you flag this question with 'applet'. In most cases, you cannot read or write a file from an Applet. — Pierre, Jan 30 '10 at 17:34
hm, do you need to convert a filename-(to/from)-file, or file _contents_ (to/from) file — Bozho, Jan 30 '10 at 17:46
Have to converted an entire File (not thecontent) in the String and then the String to the File. — Emanuel, Jan 30 '10 at 17:51
The aplication need to convert into string not only text file but any file. — Emanuel, Jan 30 '10 at 18:55
Possible duplicate: http://stackoverflow.com/questions/326390/how-to-create-a-java-string-from-the-contents-of-a-file — Anderson Green, May 18 '13 at 04:28

Bozho · Accepted Answer · 2010-01-31T16:29:31.057

NB: In both cases below you will have to digitally sign your applet, so that it is granted permissions to read/write from/to the file system!

If you can use external libraries, use Apache commons-io (you will have to sign these jars as well)

FileUtils.readFileToString(..)

FileUtils.writeStringToFile(..)

If you can't, you can see this tutorial.

This is for text files - but if you want to read binary files (.png for instance), you should not read it as string. Instead read it as byte[] and use commons-codec -

encode: String base64String = new String(Base64.encodeBase64(byteArray));

decode: byte[] originalBytes = Base64.decodeBase64(string.getByte());

Base64 is a string format for storing binary data.

+1 for mentioning that the applet must be signed to access the filesystem — stacker, Jan 30 '10 at 18:11

score 0 · Answer 2 · answered Jan 30 '10 at 17:38

public static String getFileContent(File file) throws IOException
{
FileReader in=new FileReader(file);
StringWriter w= new StringWriter();
char buffer[]=new char[2048];
int n=0;
while((n=in.read(buffer))!=-1)
 {
 w.write(buffer, 0, n);
 }
w.flush();
in.close();
return w.toString();
}

public static void toFileContent(String s,File file) throws IOException
{
FileWriter f=new FileWriter(file);
f.write(s);
f.flush();
f.close();
}

Java Applet - Convert File to String

2 Answers2