randomNumber() — netty Function Reference

Architecture documentation for the randomNumber() function in WebSocketUtil.java from the netty codebase.

Function java ProtocolCodecs HTTP

Entity Profile

ProtocolCodecs→ HTTP→ randomNumber() — netty Function Reference

Dependency Diagram

graph TD
  fbf9a1d0_ab6c_836e_a9ba_fb90ac52ecd6["randomNumber()"]
  32ad3c78_b425_e854_d489_6f60f2c146e2["WebSocketUtil"]
  fbf9a1d0_ab6c_836e_a9ba_fb90ac52ecd6 -->|defined in| 32ad3c78_b425_e854_d489_6f60f2c146e2
  style fbf9a1d0_ab6c_836e_a9ba_fb90ac52ecd6 fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

codec-http/src/main/java/io/netty/handler/codec/http/websocketx/WebSocketUtil.java lines 117–141

    static int randomNumber(int minimum, int maximum) {
        assert minimum < maximum;
        double fraction = ThreadLocalRandom.current().nextDouble();

        // the idea here is that nextDouble gives us a random value
        //
        //              0 <= fraction <= 1
        //
        // the distance from min to max declared as
        //
        //              dist = max - min
        //
        // satisfies the following
        //
        //              min + dist = max
        //
        // taking into account
        //
        //         0 <= fraction * dist <= dist
        //
        // we've got
        //
        //       min <= min + fraction * dist <= max
        return (int) (minimum + fraction * (maximum - minimum));
    }