Stream Overview

1. Lambda Expressions

Basic use

2.Optional

Basic use

3.Stream

• Creating Stream
  
  •  The final build is a ReferencePipeline.Head objects
• Followed by zero or more intermediate operations  (methods below to map an example, most logical Similarly other methods)
  • A configuration  StatelessOp objects (ReferencePipeline inner class)
    • Is essentially a construct for the intermediate operation  ReferencePipeline (ReferencePipeline constructor b)
    • Meanwhile rewrite opWrapSink method
      • Build and returns a Sink.ChainedReference objects
        • Rewrite accept method
          • Due to the termination of operation occurs, Sink will be called by the end of the stage to move forward, and therefore the type of the parameter passed to P_OUT
• Finally, add a termination operation
  • If the operation is not terminated, stream only constructed a series of objects, and objects inside the method call is not triggered, so the stream will not do anything
  • When there is no intermediate operation before the operation is terminated, for considerations of efficiency, the data source directly traverse
  • When there is an intermediate operating
    • By constructing the plant TerminalOp acquires corresponding  TerminalOp
    • evaluateSequential method call in TerminalOP
      • Call PipelineHelper of wrapAndCopyInto method (ReferencePipeline realized PipelineHelper Interface) for data to traverse