github.com/pingcap/ticdc@v0.0.0-20220526033649-485a10ef2652/pkg/workerpool/hash.go (about)

     1  // Copyright 2020 PingCAP, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // See the License for the specific language governing permissions and
    12  // limitations under the License.
    13  
    14  package workerpool
    15  
    16  // Hasher is actually a "placement driver" that balances the workload.
    17  // Non-trivial Hashers will be useful if and when we implement dynamic resizing of WorkerPool.
    18  type Hasher interface {
    19  	Hash(object Hashable) int64
    20  }
    21  
    22  // Hashable is an object that can be hashed.
    23  type Hashable interface {
    24  	HashCode() int64
    25  }
    26  
    27  type defaultHasher struct {
    28  }
    29  
    30  // Hash returns the hash value.
    31  func (m *defaultHasher) Hash(object Hashable) int64 {
    32  	return object.HashCode()
    33  }