How to use UTF-8 in resource properties with ResourceBundle

Question

I need to use UTF-8 in my resource properties using Java\'s ResourceBundle. When I enter the text directly into the properties file, it displays as mojibake.

Answer 1

Given that you have an instance of ResourceBundle and you can get String by:

String val = bundle.getString(key); 

I solved my Japanese display problem by:

return new String(val.getBytes("ISO-8859-1"), "UTF-8");

Answer 2

From Java 9, the default to load properties file has been changed to UTF-8. https://docs.oracle.com/javase/9/intl/internationalization-enhancements-jdk-9.htm

Answer 3

package com.varaneckas.utils;  

import java.io.UnsupportedEncodingException;  
import java.util.Enumeration;  
import java.util.PropertyResourceBundle;  
import java.util.ResourceBundle;  

/** 
 * UTF-8 friendly ResourceBundle support 
 *  
 * Utility that allows having multi-byte characters inside java .property files. 
 * It removes the need for Sun's native2ascii application, you can simply have 
 * UTF-8 encoded editable .property files. 
 *  
 * Use:  
 * ResourceBundle bundle = Utf8ResourceBundle.getBundle("bundle_name"); 
 *  
 * @author Tomas Varaneckas <tomas.varaneckas@gmail.com> 
 */  
public abstract class Utf8ResourceBundle {  

    /** 
     * Gets the unicode friendly resource bundle 
     *  
     * @param baseName 
     * @see ResourceBundle#getBundle(String) 
     * @return Unicode friendly resource bundle 
     */  
    public static final ResourceBundle getBundle(final String baseName) {  
        return createUtf8PropertyResourceBundle(  
                ResourceBundle.getBundle(baseName));  
    }  

    /** 
     * Creates unicode friendly {@link PropertyResourceBundle} if possible. 
     *  
     * @param bundle  
     * @return Unicode friendly property resource bundle 
     */  
    private static ResourceBundle createUtf8PropertyResourceBundle(  
            final ResourceBundle bundle) {  
        if (!(bundle instanceof PropertyResourceBundle)) {  
            return bundle;  
        }  
        return new Utf8PropertyResourceBundle((PropertyResourceBundle) bundle);  
    }  

    /** 
     * Resource Bundle that does the hard work 
     */  
    private static class Utf8PropertyResourceBundle extends ResourceBundle {  

        /** 
         * Bundle with unicode data 
         */  
        private final PropertyResourceBundle bundle;  

        /** 
         * Initializing constructor 
         *  
         * @param bundle 
         */  
        private Utf8PropertyResourceBundle(final PropertyResourceBundle bundle) {  
            this.bundle = bundle;  
        }  

        @Override  
        @SuppressWarnings("unchecked")  
        public Enumeration getKeys() {  
            return bundle.getKeys();  
        }  

        @Override  
        protected Object handleGetObject(final String key) {  
            final String value = bundle.getString(key);  
            if (value == null)  
                return null;  
            try {  
                return new String(value.getBytes("ISO-8859-1"), "UTF-8");  
            } catch (final UnsupportedEncodingException e) {  
                throw new RuntimeException("Encoding not supported", e);  
            }  
        }  
    }  
}  

Answer 4

ResourceBundle.Control with UTF-8 and new String methods don't work, if the properties file uses cp1251 charset, for example.

So I recomended using a common method: write in unicode symbols. For this:

IDEA -- has a special "Transparent native-to-ASCII conversion" option (Settings > File Encoding).

Eclipse -- has a plugin "Properties Editor". It can work as separate application.

Answer 5

http://sourceforge.net/projects/eclipse-rbe/

as already stated property files should be encoded in ISO 8859-1

You can use the above plugin for eclipse IDE to make the Unicode conversion for you.

Answer 6

look at this : http://docs.oracle.com/javase/6/docs/api/java/util/Properties.html#load(java.io.Reader)

the properties accept an Reader object as arguments, which you can create from an InputStream.

at the create time, you can specify the encoding of the Reader:

InputStreamReader isr = new InputStreamReader(stream, "UTF-8");

then apply this Reader to the load method :

prop.load(isr);

BTW: get the stream from .properties file :

 InputStream stream = this.class.getClassLoader().getResourceAsStream("a.properties");

BTW: get resource bundle from InputStreamReader:

ResourceBundle rb = new PropertyResourceBundle(isr);

hope this can help you !