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Code Analyzer for Java

There is a newer version: 8.6.0.37351

Why is this an issue?
When using the Stream API, call chains should be simplified as much as possible. Not only does it make the code easier to read, it
also avoid creating unnecessary temporary objects.
This rule raises an issue when one of the following substitution is possible:

  
    
    
  
  
    
      Original
      Preferred
    
  
  
    
      stream.filter(predicate).findFirst().isPresent()
      stream.anyMatch(predicate)
    
    
      stream.filter(predicate).findAny().isPresent()
      stream.anyMatch(predicate)
    
    
      !stream.anyMatch(predicate)
      stream.noneMatch(predicate)
    
    
      !stream.anyMatch(x -> !(...))
      stream.allMatch(...)
    
    
      stream.map(mapper).anyMatch(Boolean::booleanValue)
      stream.anyMatch(predicate)
    
  

Noncompliant code example
boolean hasRed = widgets.stream().filter(w -> w.getColor() == RED).findFirst().isPresent(); // Noncompliant

Compliant solution
boolean hasRed = widgets.stream().anyMatch(w -> w.getColor() == RED);

Original	Preferred
`stream.filter(predicate).findFirst().isPresent()`	`stream.anyMatch(predicate)`
`stream.filter(predicate).findAny().isPresent()`	`stream.anyMatch(predicate)`
`!stream.anyMatch(predicate)`	`stream.noneMatch(predicate)`
`!stream.anyMatch(x -> !(...))`	`stream.allMatch(...)`
`stream.map(mapper).anyMatch(Boolean::booleanValue)`	`stream.anyMatch(predicate)`