1. JSP pages must include the header:
<%@ page contentType="text/html; charset=UTF-8" %>
2. In the Catalina.bat (windows) catalina.sh (windows) apache$jakarta_config.com (OpenVMS), file there must be a switch added to the call to java.exe. The switch is:
-Dfile.encoding=UTF-8
I cannot find documentation for this environment variable anywhere or what it actually does but it is essential.
3. For translation of inputs coming back from the browser there must be a method that translates from the browser's ISO-8859-1 to UTF-8. It seems to me that -1 is used in all regions as I have had people in countries such as Greece & Bulgaria test this and they always send input back in -1 encoding. The method which you will use constantly should go something like this:
/** * Convert ISO8859-1 format string (which is the default sent by IE * to the UTF-8 format that the database is in. */ public String toUTF8(String isoString) { String utf8String = null; if (null != isoString && !isoString.equals("")) { try { byte[] stringBytesISO = isoString.getBytes("ISO-8859-1"); utf8String = new String(stringBytesISO, "UTF-8"); } catch(UnsupportedEncodingException e) { // As we can't translate just send back the best guess. System.out.println("UnsupportedEncodingException is: " + e.getMessage()); utf8String = isoString; } } else { utf8String = isoString; } return utf8String; }
I have found that these three steps are all that is necessary to make your site accept any language that UTF-8 can work with. I extend my thanks to those of you on the Tomcat users list who helped me find these little gems.
(from the tomcat-user mailing list)
Alternative solution
The solution suggested above works fine with steps (1) and (2) only, but from the architecture perspective the correct way is to add a filter to the Tomcat that will do necessary correction for the application deployed without any additional changes to the rest of the code.
Example of filter:
{{{import java.io.*; import java.util.*; import javax.servlet.*; import javax.servlet.http.*;
public class CharsetFilter implements Filter
{
private String encoding;
public void init(FilterConfig config) throws ServletException
{
encoding = config.getInitParameter("requestEncoding");
if( encoding==null ) encoding="UTF-8";
}
public void doFilter(ServletRequest request, ServletResponse response, FilterChain next)
throws IOException, ServletException
{
request.setCharacterEncoding(encoding);
next.doFilter(request, response);
}
public void destroy(){}
}
}}}
Corresponding portion of web.xml configuration will look like:
<!--CharsetFilter start--> <filter> <filter-name>Charset Filter</filter-name> <filter-class>CharsetFilter</filter-class> <init-param> <param-name>requestEncoding</param-name> <param-value>UTF-8</param-value> </init-param> </filter> <filter-mapping> <filter-name>Charset Filter</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> <!--CharsetFilter end-->
The suggested solution originates from [http://people.comita.spb.ru/users/sergeya/java/ruschars.html Sergey Astakhov (all texts are in russian)] (sergeya@comita.spb.ru)