github.com/m3db/m3@v1.5.0/src/x/ident/bytes_id.go (about)

     1  // Copyright (c) 2018 Uber Technologies, Inc.
     2  //
     3  // Permission is hereby granted, free of charge, to any person obtaining a copy
     4  // of this software and associated documentation files (the "Software"), to deal
     5  // in the Software without restriction, including without limitation the rights
     6  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
     7  // copies of the Software, and to permit persons to whom the Software is
     8  // furnished to do so, subject to the following conditions:
     9  //
    10  // The above copyright notice and this permission notice shall be included in
    11  // all copies or substantial portions of the Software.
    12  //
    13  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    14  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    15  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    16  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    17  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    18  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    19  // THE SOFTWARE.
    20  
    21  package ident
    22  
    23  import (
    24  	"bytes"
    25  )
    26  
    27  // BytesID is a small utility type to avoid the heavy weight of a true ID
    28  // implementation when using in high throughput places like keys in a map.
    29  type BytesID []byte
    30  
    31  // var declaration to ensure package type BytesID implements ID
    32  var _ ID = BytesID(nil)
    33  
    34  // Bytes returns the underlying byte slice of the bytes ID.
    35  func (v BytesID) Bytes() []byte {
    36  	return v
    37  }
    38  
    39  // String returns the bytes ID as a string.
    40  func (v BytesID) String() string {
    41  	return string(v)
    42  }
    43  
    44  // Equal returns whether the bytes ID is equal to a given ID.
    45  func (v BytesID) Equal(value ID) bool {
    46  	return bytes.Equal(value.Bytes(), v)
    47  }
    48  
    49  // NoFinalize is a no-op for a bytes ID as Finalize is already a no-op.
    50  func (v BytesID) NoFinalize() {
    51  }
    52  
    53  // IsNoFinalize is always true since BytesID is not pooled.
    54  func (v BytesID) IsNoFinalize() bool {
    55  	return true
    56  }
    57  
    58  // Finalize is a no-op for a bytes ID as it has no associated pool.
    59  func (v BytesID) Finalize() {
    60  }
    61  
    62  var _ ID = (*ReusableBytesID)(nil)
    63  
    64  // ReusableBytesID is a reusable bytes ID, use with extreme care in
    65  // places where the lifecycle is known (there is no checking with this
    66  // ID).
    67  type ReusableBytesID struct {
    68  	bytes []byte
    69  }
    70  
    71  // NewReusableBytesID returns a new reusable bytes ID, use with extreme
    72  // care in places where the lifecycle is known (there is no checking with
    73  // this ID).
    74  func NewReusableBytesID() *ReusableBytesID {
    75  	return &ReusableBytesID{}
    76  }
    77  
    78  // Reset resets the bytes ID for reuse, make sure there are zero references
    79  // to this ID from any other data structure at this point.
    80  func (i *ReusableBytesID) Reset(bytes []byte) {
    81  	i.bytes = bytes
    82  }
    83  
    84  // Bytes implements ID.
    85  func (i *ReusableBytesID) Bytes() []byte {
    86  	return i.bytes
    87  }
    88  
    89  // Equal implements ID.
    90  func (i *ReusableBytesID) Equal(value ID) bool {
    91  	return bytes.Equal(i.bytes, value.Bytes())
    92  }
    93  
    94  // NoFinalize implements ID.
    95  func (i *ReusableBytesID) NoFinalize() {
    96  }
    97  
    98  // IsNoFinalize implements ID.
    99  func (i *ReusableBytesID) IsNoFinalize() bool {
   100  	// Reusable bytes ID are always not able to not be finalized
   101  	// as this ID is reused with reset.
   102  	return false
   103  }
   104  
   105  // Finalize implements ID.
   106  func (i *ReusableBytesID) Finalize() {
   107  	// Noop as it will be re-used.
   108  }
   109  
   110  // String returns the bytes ID as a string.
   111  func (i *ReusableBytesID) String() string {
   112  	return string(i.bytes)
   113  }