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Java 8 - Streams - Collectors - Partition By



  • partitionBy operation on Collectors provides a way to aggregate the result of a stream operation into a map.
  • The map contains two items which are the result partitions based on a predicate function.

stream of employees
Stream employees = Stream.of( new Employee("Joe", "Blogs", "Sales", 100.0), new Employee("Richardo", "Banks", "Engineering", 50.0), new Employee("Hewlet", "Packer", "Warehouse", 40.0) );


USAGE

 Map<Boolean, List<Employee>> employeePartitions = employees .collect(Collectors.partitioningBy(employee -> employee.getSalary() > 50));
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