Groovy Boolean Evaluation
Boolean evaluation in Groovy is different than in Java. Depending on the context, Groovy will automatically evaluate expressions as boolean.
Let’s see a specific example. The following Java code will not work:
| | //Java code |
| | String obj = "hello"; |
| | int val = 4; |
| | if (obj) {} // ERROR |
| | if(val) {} //ERROR |
Java insists that we provide a boolean expression for the condition part of the if statement. It wants if(obj != null) and if(val > 0) in the previous example, for instance.
Groovy is not that picky. It tries to infer, so we need to know what Groovy is thinking.
If we place an object reference where a boolean expression is expected, Groovy checks whether the reference is null. It considers null
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