Java properties UTF-8 encoding in Eclipse

Question

I've recently had to switch encoding of webapp I'm working on from ISO-xx to utf8. Everything went smooth, except properties files. I added -Dfile.encoding=UTF-8 in eclipse.ini and normal files work fine. Properties however show some strange behaviour.

If I copy utf8 encoded properties from Notepad++ and paste them in Eclipse, they show and work fine. When I reopen properties file, I see some Unicode characters instead of proper ones, like:

Zur\u00EF\u00BF\u00BDck instead of Zurück 

but app still works fine. If I start to edit properties, add some special characters and save, they display correctly, however they don't work and all previously working special characters don't work any more.

When I compare local version with CVS I can see special characters correctly on remote file and after update I'm at start again: app works, but Eclipse displays Unicode chars.

I tried changing file encoding by right clicking it and selecting „Other: UTF8” but it didn't help. It also said: „determined from content: ISO-8859-1”

I'm using Java 6 and Jboss Developer based on Eclipse 3.3

I can live with it by editing properties in Notepad++ and pasting them in Eclipse, but I would be grateful if someone could help me with fixing this in Eclipse.

Answer 1

Answer for "pre-Java-9" is below. As of Java 9, properties files are saved and loaded in UTF-8 by default, but falling back to ISO-8859-1 if an invalid UTF-8 byte sequence is detected. See the Java 9 release notes for details.

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Properties files are ISO-8859-1 by definition - see the docs for the Properties class.

Spring has a replacement which can load with a specified encoding, using PropertiesFactoryBean.

EDIT: As Laurence noted in the comments, Java 1.6 introduced overloads for load and store which take a Reader/Writer. This means you can create a reader for the file with whatever encoding you want, and pass it to load. Unfortunately FileReader still doesn't let you specify the encoding in the constructor (aargh) so you'll be stuck with chaining FileInputStream and InputStreamReader together. However, it'll work.

For example, to read a file using UTF-8:

Properties properties = new Properties(); InputStream inputStream = new FileInputStream("path/to/file"); try {     Reader reader = new InputStreamReader(inputStream, "UTF-8");     try {         properties.load(reader);     } finally {         reader.close();     } } finally {    inputStream.close(); }