Java MessageFormat Null Values
What is the best way to treat null values in Java MessageFormat
MessageFormat.format("Value: {0}",null);
=> Value: null
but actually a "Value: " would be nice.
Same with date
MessageFormat.format("Value: {0,date,medium}",null);
=> Value: null
a "Value: " whould be much more appreciated.
Is there any way to do this? I tried choice
{0,choice,null#|notnull#{0,date,dd.MM.yyyy – HH:mm:ss}}
which results in invalid choice format, what is correct to check for "null" or "not null"?
Answer
MessageFormat is only null-tolerant; that is, it will handle a null argument. If you want to have a default value appear instead of something if the value you're working with is null, you have two options:
You can either do a ternary...
MessageFormat.format("Value: {0}", null == value ? "" : value));
...or use StringUtils.defaultIfBlank() from commons-lang instead:
MessageFormat.format("Value: {0}", StringUtils.defaultIfBlank(value, ""));