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error: illegal character: '\ufeff' in java

Got this error when compiled java code in ubuntu.
![Got this error][1]
error: illegal character: '\ufeff'
import java.net.*;
^
error: class, interface, or enum expected
import java.net.*;
^

As Jim Garrison pointed out, you probably have a Byte Order Marker (BOM) at the start of the file. Use an editor that can view all non-printable characters and remove it.
Alternatively, you can use sed to remove it:
sed '1s/^.//' infile >> outfile

If you are using IntelliJ, right click on the class file and select 'Remove BOM'.
That should remove the BOM at the start.

In case your are working on Windows O.S. and use Eclipse (which don't have the functionality to remove the BOM from the file), just open the file in Notepad++ and in the encoding menu, select "UTF-8", then save the file.

Use another editor because it seems to be an eclipse UTF-8-BOM problem.
Convert the UTF type UTF-8.
And also I note that ; First it doesn't work for me and I convert the type ANSI and after convert type to UTF-8 format. It can be a another alternative solution for you

downloading models from https://codebeautify.org/json-to-java-converter is causing such problems.
create new file and copy/paste all data from the downloaded file.

Java encoding issue with ├ └

If I print
System.out.println("│ ├── └──");
I see only question marks (???). Seams that this is some king of encoding problem. Any ideas how to fix this?

Use the UTF-8 codes instead of the actual characters. For example ├ is \u251c.
Here is a link that will help you convert characters to corresponding codes: http://www.cylog.org/online_tools/utf8_converter.jsp
Hope it helps!

Any ideas how to fix this?
There are two possible causes of your problem:
1) It could be happening when you edit compile source code. The compiler could be reading the source code using a different file encoding to the one that you are using when you edit it. If you don't specify a source file encoding, the compiler will use a platform-specific default, and that might not be the right one.
The fix for this is to adjust your compiler settings to specify the correct source file encoding. How you do that will depend on how you are compiling. If you are compiling from the command line using javac, use the -encoding option.
Alternatively, a workaround for this problem is to replace the offending in your source code with Unicode escapes. For example:
String s = "\u251c";
should give you a one character string consisting of a "├" character. I would recommend the workaround. Source code that includes non-ASCII characters is always going to be sensitive to how you edit and compile ... and that is not a good thing.
2) It could be happening because there is a mismatch between your Java runtime platform's default output encoding and the actual encoding of whatever is displaying the output.
The fix for this is one of:
change the encoding for the display,
override the default encoding for the JVM (e.g. using -Dfile.encoding=UTF-8), or
change your code to output using a specific encoding.
Which is best depends on the circumstances; e.g. why things are "wrong" in the first place.
It is worth running this test application from the command prompt to see if the problem exists their too. If it does, then redirect standard output to a file, and use a hex dump utility (e.g. od on Linux) to see how the characters are encoded. That will help you distinguish causes 1) and 2) above.
(It is also possible that you have both problems ...)

The encoding of the java file (editor( and the encoding that the javac compiler better both use UTF-8. This generally is a IDE or project setting.
One might check that both encodings are equal, by the u-escaping of those chars: \u251C etcetera,
System.out must use the operating system encoding. If that encoding cannot convert those characters, one might see a ?. If the console is a console emulation of the IDE, you might search the setting of that encoding. Also check that the console font contains those graphic chars. Running the IDE with java -Dfile.encoding UTF-8 might help.
In your case: Strange. Check the source encoding with gedit, dump System.getProperty("file,encoding").

Java, Ant error: unmappable character for encoding Cp1252

I am using Java, Eclipse and Ant in my project. I had some Java code that I needed to edit and add some UTF-8 chars in them. Previously my build.xml had:
And it worked fine. Now after adding those UTF-8 chars when I try to run, it throws "error: unmappable character for encoding Cp1252"
Could anyone please tell me what is the fix? I tried changing the encoding to UTF-8 and Cp1252 in the xml but with no luck.
I'm using JRE7, Eclipse Kepler and Ant 4.11.

This can be tricky simply changing the "advertised" encoding does not make up for the fact that there are bytes in the file that cannot be understood using a UTF-8 interpretation. In Ant you will need to update the javac task to add an encoding like, <javac ... encoding="utf-8">
Make sure that the file encoding in Eclipse is also UTF-8 because some cp1252 characters do not directly map into UTF-8 either. You will probably want to maintain your entire project using a single encoding. Otherwise the compiler will be seeing different encodings when it only expects one.

You can try to set the environment variable called ANT_OPTS (or JAVA_TOOL_OPTIONS) to -Dfile.encoding=UTF8

Had the similar issue in one of my projects. Some of my files had UTF-8 characters and due to eclipse default encoding - cp1252, build failed with this error.
To resolve the issue, follow the below steps -
Change the encoding at eclipse project level to UTF-8 (Project properties -> "Text file encoding" -> select "Other" option -> select "UTF-8" from the drop down)
Add encoding attribute for javac task in ant build script with value "UTF-8"
Set the encoding type according to the special characters used in your code/files.

Go to common tab of RUN/DEBUG configuration in eclipse change encoding to UTF-8.

Window > Preferences > General > Content Types, set UTF-8 as the default encoding for all content types.
Window > Preferences > General > Workspace, set "Text file encoding" to "Other : UTF-8".

Maven filter garbling special characters

I have a resource file with the following string in it, note the special characters:
Questa funzionalità non è sostenuta: {0} {1}
After Maven does its process-resources (which I need for something else) I get:
Questa funzionalit� non � sostenuta: {0} {1}
Please tell me there is an easy fix to this?

The text files that held the strings were Java properties files. By default, most files in an Eclipse project inherit the default encoding scheme from the container (Eclipse) -- in my case that is UTF-8. If you just manually add a text file to the project it does not set it to UTF-8!!
So my properties files were actually encoded as ISO-8859-1. I changed the default encoding in Eclipse by clicking right on the file and selecting properties. I then was forced to re-enter ALL the special characters.
The other part of the fix was to tell the Maven process resource plug-in to use UTF-8 encoding while processing resources. Instructions for that are here:
http://maven.apache.org/plugins/maven-resources-plugin/examples/encoding.html
And of course I had to implement a UTF-8 ResourceBundle.Control because (for backwards compatibility) the detault ResourceBundle is still ISO-8859-1. Details on that class can be found here:
http://www.mail-archive.com/stripes-users#lists.sourceforge.net/msg03972.html
Hope this helps somebody someday.

Illegal Character when trying to compile java code

I have a program that allows a user to type java code into a rich text box and then compile it using the java compiler. Whenever I try to compile the code that I have written I get an error that says that I have an illegal character at the beginning of my code that is not there. This is the error the compiler is giving me:
C:\Users\Travis Michael>"\Program Files\Java\jdk1.6.0_17\bin\javac" Test.java
Test.java:1: illegal character: \187
public class Test
^
Test.java:1: illegal character: \191
public class Test
^
2 errors

The BOM is generated by, say, File.WriteAllText() or StreamWriter when you don't specify an Encoding. The default is to use the UTF8 encoding and generate a BOM. You can tell the java compiler about this with its -encoding command line option.
The path of least resistance is to avoid generating the BOM. Do so by specifying System.Text.Encoding.Default, that will write the file with the characters in the default code page of your operating system and doesn't write a BOM. Use the File.WriteAllText(String, String, Encoding) overload or the StreamWriter(String, Boolean, Encoding) constructor.
Just make sure that the file you create doesn't get compiled by a machine in another corner of the world. It will produce mojibake.

That's a byte order mark, as everyone says.
javac does not understand the BOM, not even when you try something like
javac -encoding UTF8 Test.java
You need to strip the BOM or convert your source file to another encoding. Notepad++ can convert a single files encoding, I'm not aware of a batch utility on the Windows platform for this.
The java compiler will assume the file is in your platform default encoding, so if you use this, you don't have to specify the encoding.

If using an IDE, specify the java file encoding (via the properties panel)
If NOT using an IDE, use an advanced text-editor (I can recommend Notepad++) and set the encoding to "UTF without BOM", or "ANSI", if that suits you.

In this case do the following Steps 1-7
In Android Studio
1. Menu -> Edit -> Select All
2. Menu -> Edit -> Cut
Open new Notepad.exe
In Notepad
4. Menu -> Edit -> Paste
5. Menu -> Edit -> Select All
6. Menu -> Edit -> Copy
Back In Android Studio
7. Menu -> Edit -> Paste

http://en.wikipedia.org/wiki/Byte_order_mark
The byte order mark (BOM) is a Unicode
character used to signal the
endianness (byte order) of a text file
or stream. Its code point is U+FEFF.
BOM use is optional, and, if used,
should appear at the start of the text
stream. Beyond its specific use as a
byte-order indicator, the BOM
character may also indicate which of
the several Unicode representations
the text is encoded in.
The BOM is a funky-looking character that you sometimes find at the start of unicode streams, giving a clue what the encoding is. It's usually handles invisibly by the string-handling stuff in Java, so you must have confused it somehow, but without seeing your code, it's hard to see where.
You might be able to fix it trivially by manually stripping the BOM from the string before feeding it to javac. It probably qualifies as whitespace, so try calling trim() on the input String, and feeding the output of that to javac.

That's a problem related to BOM (Byte Order Mark) character. Byte Order Mark BOM is an Unicode character used for defining a text file byte order and comes in the start of the file. Eclipse doesn't allow this character at the start of your file, so you must delete it. for this purpose, use a rich text editor like Notepad++ and save the file with encoding "UTF-8 without BOM". That should remove the problem.
I have copy pasted the some content from a website to a Notepad++ editor,
it shows the "LS" with black background. Have deleted the "LS" content and
have copy the same content from notepad++ to java file, it works fine.

I solved this by right clicking in my textEdit program file and selecting [substitutions] and un-checking smart quotes.

instead of getting Notepad++,
You can simply
Open the file with Wordpad
and then
Save As - Plain Text document

Even I was facing this issue as am using notepad++ to code. It is very convenient to type the code in notepad++. However after compiling I get an error " error: illegal character: '\u00bb'".
Solution :
Start writing the code in older version of notepad(which will be there by default in your PC) and save it. Later the modifications can be done using notepad++.
It works!!!

I had the same problem with a file i generated using the command echo echo "" > Main.java in Windows Powershell. I searched the problem and it seemed to have something to do with encoding. I checked the encoding of the file using file -i Main.java and the result was text/plain; charset=utf-16le.
Later i deleted the file and recreated it using git bash using touch Main.java and with this the file compiled successfully. I checked the file encoding using file -i command and this time the result was Main.java: text/x-c; charset=us-ascii.
Next i searched the internet and found that to create an empty file using Powershell we can use the Cmdlet New-Item. I create the file using New-Item Main.java and checked it's encoding and this time the result was Main.java: text/x-c; charset=us-ascii and this time it compiled successully.