Question: I need to convert string to letter case (proper case or title case), is there any default function on Groovy support for this or I need to manual sub string convert first character?

Answer: 
```
assert org.apache.commons.lang.WordUtils.capitalizeFully('man OF stEEL') == 'Man Of Steel'

```

The `WordUtils` class is provided by Apache Commons Lang, which is available on the classpath of Grails apps by defatult
yes, you can use the method capitalize() 

<http://groovy.codehaus.org/groovy-jdk/java/lang/String.html#capitalize%28%29>