Convert escaped Unicode character back to actual character

try

str = org.apache.commons.lang3.StringEscapeUtils.unescapeJava(str);

from Apache Commons Lang

java.util.Properties

You can take advantage of the fact that java.util.Properties supports strings with '\uXXXX' escape sequences and do something like this:

Properties p = new Properties();
p.load(new StringReader("key="+yourInputString));
System.out.println("Escaped value: " + p.getProperty("key"));

Inelegant, but functional.

To handle the possible IOExeception, you may want a try-catch.

Properties p = new Properties();
try { p.load( new StringReader( "key=" + input ) ) ; } catch ( IOException e ) { e.printStackTrace(); }
System.out.println( "Escaped value: " + p.getProperty( "key" ) );