What is the "?:" operator used for in Groovy? - Stack Overflow
2016年1月5日 · 3. "Yes, the "?:" operator will return the value to the left, if it is not null." - That is incorrect. There are non-null values for which the operator will return the value to the right (empty list, empty String, number zero, false, etc.). The operator returns the value on the left if the value on the left evaluates to "true" per Groovy truth ...
variables - What does [:] mean in groovy? - Stack Overflow
2017年9月6日 · 16. [:] creates an empty Map. The colon is there to distinguish it from [], which creates an empty List. This groovy code: def foo = [:] is roughly equivalent to this java code: Object foo = new java.util.LinkedHashMap(); answered Apr 4, 2014 at 14:13. Sean Reilly.
What is the difference between ==~ and != in Groovy?
In Groovy you also have to be aware that in addition to ==~, alias "Match operator", there is also =~, alias "Find Operator" and ~, alias "Pattern operator". All are explained here. ==~ result type: Boolean/boolean (there are no primitives in Groovy, all is not what it seems!) =~ result type: java.util.regex.Matcher ~ result type: java.util ...
Use literal operators (eg "and", "or") in Groovy expressions?
2012年12月8日 · Recent versions of Groovy support Command chains, so it's indeed possible to write this: compute x > 10 and y == 20 or not(z) The word "compute" here is arbitrary, but it cannot be omitted, because it's the first "verb" in the command chain. Everything that follows alternates between verb and noun: compute x > 10 and y == 20 or not(z
Groovy: println vs System.out.println with GroovyInterceptable
2015年6月4日 · Invoke method total with args: [2, 3] The call to println inside invokeMethod is thus understood as a call to this.println, just like a call to sum would be. But this.println just calls invokeMethod again, because you implemented GroovyInterceptable, and so on. This wouldn't happen if you didn't implement GroovyInterceptable.
How to call Java's Stream.collect() from groovy? - Stack Overflow
2015年10月19日 · Groovy translates the call to the DefaultGroovyMethods.collect() instead of Stream.collect() that I originally wanted to use. Of course then the last line would be: .collect(Collectors.toList()) //Should call Java collect, but it doesn't. It seems counter-intuitive to me, that some extension method is called instead of native, 'built-in' method ...
java - for each loop in groovy - Stack Overflow
this is exactly how the each and all other groovy collection methods are built: they just blindnly iterate through one be one. If you need another iteration logic, you must stick with traditional loops –
grails - Using "$" in Groovy - Stack Overflow
In a GString (groovy string), any valid Groovy expression can be enclosed in the ${...} including method calls etc. This is detailed in the following page . Share
Groovy executing shell commands - Stack Overflow
Groovy adds the execute method to String to make executing shells fairly easy; println "ls".execute().text ...
groovy - Splitting String with delimiter - Stack Overflow
2018年6月8日 · It works like this: I think It's very useful to add an edge case that you might run into when spliting by the '.' char. So you'll must need to escape the dot if you want to split on a literal dot: String extensionRemoved = filename.split("\\.")[0]; Otherwise you are splitting on the regex ., which means "any character".