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Version: 2.9.x
tip

The following is a list of commonly used methods; documentation updates may lag behind new features in the code. For more methods and examples, please refer to the code documentation: https://pkg.go.dev/github.com/gogf/gf/v2/container/gtree

tip

For generic versions of tree containers (such as AVLKVTree[K, V], BKVTree[K, V], RedBlackKVTree[K, V]), the framework provides NilChecker functions to customize "which values should be considered nil" to solve typed nil determination issues when containing pointers, interfaces, and other types. Lazy loading or conditional write methods (such as GetOrSet*, SetIfNotExist* series) will call this function before actually writing, and usually won't write the key-value pair when determined as nil; when NilChecker is not set, behavior remains consistent with historical versions.

  • Description: Generic versions of various tree containers provide constructors with NilChecker and runtime registration methods, including (mainly illustrative):

    • NewAVLKVTreeWithChecker(comparator func(v1, v2 K) int, checker NilChecker[V], safe ...bool) *AVLKVTree[K, V]
    • NewAVLKVTreeWithCheckerFrom(comparator func(v1, v2 K) int, data map[K]V, checker NilChecker[V], safe ...bool) *AVLKVTree[K, V]
    • NewBKVTreeWithChecker(m int, comparator func(v1, v2 K) int, checker NilChecker[V], safe ...bool) *BKVTree[K, V]
    • NewBKVTreeWithCheckerFrom(m int, comparator func(v1, v2 K) int, data map[K]V, checker NilChecker[V], safe ...bool) *BKVTree[K, V]
    • NewRedBlackKVTreeWithChecker(comparator func(v1, v2 K) int, checker NilChecker[V], safe ...bool) *RedBlackKVTree[K, V]
    • NewRedBlackKVTreeWithCheckerFrom(comparator func(v1, v2 K) int, data map[K]V, checker NilChecker[V], safe ...bool) *RedBlackKVTree[K, V]
    • func (tree *AVLKVTree[K, V]) RegisterNilChecker(checker NilChecker[V])
    • func (tree *BKVTree[K, V]) RegisterNilChecker(checker NilChecker[V])
    • func (tree *RedBlackKVTree[K, V]) RegisterNilChecker(checker NilChecker[V])

  • Purpose: Through NilChecker, customize "which values are considered nil". Lazy loading/conditional write methods (such as GetOrSet*, SetIfNotExist* series) will call this function before actually writing, and usually won't write the key-value pair when determined as nil.

  • Example (using RedBlackKVTree as example):

func ExampleRedBlackKVTree_NilChecker() {
    type Student struct {
        Name string
    }

    // Use constructor to specify NilChecker, treat *Student(nil) as "no value", won't write to tree
    tr := gtree.NewRedBlackKVTreeWithChecker[int, *Student](gutil.ComparatorInt, func(s *Student) bool {
        return s == nil
    }, true)

    v1 := tr.GetOrSetFunc(1, func() *Student {
        return nil
    })
    fmt.Println(v1 == nil)
    fmt.Println(tr.Contains(1))

    // Can also create first, then register determination logic via RegisterNilChecker
    tr2 := gtree.NewRedBlackKVTree[int, *Student](gutil.ComparatorInt, true)
    tr2.RegisterNilChecker(func(s *Student) bool {
        return s == nil
    })

    v2 := tr2.GetOrSetFunc(2, func() *Student {
        return nil
    })
    fmt.Println(v2 == nil)
    fmt.Println(tr2.Contains(2))

    // Output:
    // true
    // false
    // true
    // false
}

NewBTree​

  • Description: NewBTree creates a BTree using m (maximum number of child nodes) and a custom comparator. The safe parameter specifies whether to use a concurrency-safe tree, with a default value of false.

  • Note: The m parameter must be greater than or equal to 3, otherwise it will panic.

  • Format:

NewBTree(m int, comparator func(v1, v2 interface{}) int, safe ...bool) *BTree
  • Example:
func ExampleNewBTree() {
      bTree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          bTree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }
      fmt.Println(bTree.Map())

      // Output:
      // map[key0:val0 key1:val1 key2:val2 key3:val3 key4:val4 key5:val5]
}

NewBTreeFrom​

  • Description: NewBTreeFrom creates a BTree using m (maximum number of child nodes), a custom comparator, and data of type map[interface{}]interface{}. The safe parameter specifies whether to use a concurrency-safe tree, with a default value of false.

  • Note: The m parameter must be greater than or equal to 3, otherwise it will panic.

  • Format:

NewBTreeFrom(m int, comparator func(v1, v2 interface{}) int, data map[interface{}]interface{}, safe ...bool) *BTree
  • Example:
func ExampleNewBTreeFrom() {
      bTree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          bTree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      otherBTree := gtree.NewBTreeFrom(3, gutil.ComparatorString, bTree.Map())
      fmt.Println(otherBTree.Map())

      // Output:
      // map[key0:val0 key1:val1 key2:val2 key3:val3 key4:val4 key5:val5]
}

Clone​

  • Description: Clone returns a new BTree, which is a copy of the current tree.

  • Format:

Clone() *BTree
  • Example:
func ExampleBTree_Clone() {
      b := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          b.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      tree := b.Clone()

      fmt.Println(tree.Map())
      fmt.Println(tree.Size())

      // Output:
      // map[key0:val0 key1:val1 key2:val2 key3:val3 key4:val4 key5:val5]
      // 6
}

Set​

  • Description: Set sets the key/value for the tree.

  • Format:

Set(key interface{}, value interface{})
  • Example:
func ExampleBTree_Set() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      fmt.Println(tree.Map())
      fmt.Println(tree.Size())

      // Output:
      // map[key0:val0 key1:val1 key2:val2 key3:val3 key4:val4 key5:val5]
      // 6
}

Sets​

  • Description: Sets sets key/value for the tree in batches.

  • Format:

Sets(data map[interface{}]interface{})
  • Example:
func ExampleBTree_Sets() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)

      tree.Sets(map[interface{}]interface{}{
          "key1": "val1",
          "key2": "val2",
      })

      fmt.Println(tree.Map())
      fmt.Println(tree.Size())

      // Output:
      // map[key1:val1 key2:val2]
      // 2
}

Get​

  • Description: Get returns the value value corresponding to the parameter key. If key does not exist, it returns Nil.

  • Format:

Get(key interface{}) (value interface{})
  • Example:
func ExampleBTree_Get() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      fmt.Println(tree.Get("key1"))
      fmt.Println(tree.Get("key10"))

      // Output:
      // val1
      // <nil>
}

GetOrSet​

  • Description: GetOrSet returns value if key exists; if key does not exist, it sets the key-value with key and value, then returns the value.

  • Format:

GetOrSet(key interface{}, value interface{}) interface{}
  • Example:
func ExampleBTree_GetOrSet() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      fmt.Println(tree.GetOrSet("key1", "newVal1"))
      fmt.Println(tree.GetOrSet("key6", "val6"))

      // Output:
      // val1
      // val6
}

GetOrSetFunc​

  • Description: GetOrSetFunc returns value if key exists; if key does not exist, it sets the key-value with key and the return value of func f, then returns the value.

  • Format:

GetOrSetFunc(key interface{}, f func() interface{}) interface{}
  • Example:
func ExampleBTree_GetOrSetFunc() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      fmt.Println(tree.GetOrSetFunc("key1", func() interface{} {
          return "newVal1"
      }))
      fmt.Println(tree.GetOrSetFunc("key6", func() interface{} {
          return "val6"
      }))

      // Output:
      // val1
      // val6
}

GetOrSetFuncLock​

  • Description: GetOrSetFunc returns value if key exists; if key does not exist, it sets the key-value with key and the return value of func f, then returns the value.

  • Note: The difference between GetOrSetFuncLock and GetOrSetFunc is that it executes the function f in a write lock.

  • Format:

GetOrSetFuncLock(key interface{}, f func() interface{}) interface{}
  • Example:
func ExampleBTree_GetOrSetFuncLock() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      fmt.Println(tree.GetOrSetFuncLock("key1", func() interface{} {
          return "newVal1"
      }))
      fmt.Println(tree.GetOrSetFuncLock("key6", func() interface{} {
          return "val6"
      }))

      // Output:
      // val1
      // val6
}

GetVar​

  • Description: GetVar searches and returns the key value corresponding to the key name key, the type is *gvar.Var.

  • Note: The returned gvar.Var is not concurrent safe.

  • Format:

GetVar(key interface{}) *gvar.Var
  • Example:
func ExampleBTree_GetVar() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      fmt.Println(tree.GetVar("key1").String())

      // Output:
      // val1
}

GetVarOrSet​

  • Description: GetVarOrSet returns the result of GetOrSet, the type is *gvar.Var.

  • Note: The returned gvar.Var is not concurrent safe.

  • Format:

GetVarOrSet(key interface{}, value interface{}) *gvar.Var
  • Example:
func ExampleBTree_GetVarOrSet() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      fmt.Println(tree.GetVarOrSet("key1", "newVal1"))
      fmt.Println(tree.GetVarOrSet("key6", "val6"))

      // Output:
      // val1
      // val6
}

GetVarOrSetFunc​

  • Description: GetVarOrSetFunc returns the result of GetOrSetFunc, the type is *gvar.Var.
  • Note: The returned gvar.Var is not concurrent safe.
  • Format:
GetVarOrSetFunc(key interface{}, f func() interface{}) *gvar.Var
  • Example:
func ExampleBTree_GetVarOrSetFunc() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      fmt.Println(tree.GetVarOrSetFunc("key1", func() interface{} {
          return "newVal1"
      }))
      fmt.Println(tree.GetVarOrSetFunc("key6", func() interface{} {
          return "val6"
      }))

      // Output:
      // val1
      // val6
}

GetVarOrSetFuncLock​

  • Description: GetVarOrSetFuncLock returns the result of GetOrSetFuncLock, the type is *gvar.Var.

  • Note: The returned gvar.Var is not concurrent safe.

  • Format:

GetVarOrSetFuncLock(key interface{}, f func() interface{}) *gvar.Var
  • Example:
func ExampleBTree_GetVarOrSetFuncLock() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      fmt.Println(tree.GetVarOrSetFuncLock("key1", func() interface{} {
          return "newVal1"
      }))
      fmt.Println(tree.GetVarOrSetFuncLock("key6", func() interface{} {
          return "val6"
      }))

      // Output:
      // val1
      // val6
}

SetIfNotExist​

  • Description: If key does not exist, SetIfNotExist sets the key-value pair key/value for the map and returns true. If key exists, it returns false, and value will be ignored.

  • Format:

SetIfNotExist(key interface{}, value interface{}) bool
  • Example:
func ExampleBTree_SetIfNotExist() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      fmt.Println(tree.SetIfNotExist("key1", "newVal1"))
      fmt.Println(tree.SetIfNotExist("key6", "val6"))

      // Output:
      // false
      // true
}

SetIfNotExistFunc​

  • Description: If key does not exist, SetIfNotExistFunc sets the value to the return value of the function f and returns true. If key exists, it returns false, and value will be ignored.

  • Format:

SetIfNotExistFunc(key interface{}, f func() interface{}) bool
  • Example:
func ExampleBTree_SetIfNotExistFunc() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      fmt.Println(tree.SetIfNotExistFunc("key1", func() interface{} {
          return "newVal1"
      }))
      fmt.Println(tree.SetIfNotExistFunc("key6", func() interface{} {
          return "val6"
      }))

      // Output:
      // false
      // true
}

SetIfNotExistFuncLock​

  • Description: If key does not exist, SetIfNotExistFunc sets the value to the return value of func c, then returns true. If key exists, it returns false, and value will be ignored.

  • The difference between SetIfNotExistFuncLock and SetIfNotExistFunc is that it executes the function f within mutex.Lock.

  • Format:

SetIfNotExistFuncLock(key interface{}, f func() interface{}) bool
  • Example:
func ExampleBTree_SetIfNotExistFuncLock() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      fmt.Println(tree.SetIfNotExistFuncLock("key1", func() interface{} {
          return "newVal1"
      }))
      fmt.Println(tree.SetIfNotExistFuncLock("key6", func() interface{} {
          return "val6"
      }))

      // Output:
      // false
      // true
}

Contains​

  • Description: Contains checks if key exists in the tree. If key exists, it returns true; otherwise, it returns false.

  • Format:

Contains(key interface{}) bool
  • Example:
func ExampleBTree_Contains() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      fmt.Println(tree.Contains("key1"))
      fmt.Println(tree.Contains("key6"))

      // Output:
      // true
      // false
}

Remove​

  • Description: Delete the value from tree according to the given key and return this deleted value.

  • Format:

Remove(key interface{}) (value interface{})
  • Example:
func ExampleBTree_Remove() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      fmt.Println(tree.Remove("key1"))
      fmt.Println(tree.Remove("key6"))
      fmt.Println(tree.Map())

      // Output:
      // val1
      // <nil>
      // map[key0:val0 key2:val2 key3:val3 key4:val4 key5:val5]
}

Removes​

  • Description: Removes deletes value of tree in batches according to the given key.

  • Format:

Removes(keys []interface{})
  • Example:
func ExampleBTree_Removes() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      removeKeys := make([]interface{}, 2)
      removeKeys = append(removeKeys, "key1")
      removeKeys = append(removeKeys, "key6")

      tree.Removes(removeKeys)

      fmt.Println(tree.Map())

      // Output:
      // map[key0:val0 key2:val2 key3:val3 key4:val4 key5:val5]
}

IsEmpty​

  • Description: IsEmpty checks if tree is empty. If tree is empty, it returns true; otherwise, it returns false.

  • Format:

IsEmpty() bool
  • Example:
func ExampleBTree_IsEmpty() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)

      fmt.Println(tree.IsEmpty())

      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      fmt.Println(tree.IsEmpty())

      // Output:
      // true
      // false
}

Size​

  • Description: Size returns the size of the tree.

  • Format:

Size() int
  • Example:
func ExampleBTree_Size() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)

      fmt.Println(tree.Size())

      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      fmt.Println(tree.Size())

      // Output:
      // 0
      // 6
}

Keys​

  • Description: Keys returns all keys in ascending order.

  • Format:

Keys() []interface{}
  • Example:
func ExampleBTree_Keys() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 6; i > 0; i-- {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      fmt.Println(tree.Keys())

      // Output:
      // [key1 key2 key3 key4 key5 key6]
}

Values​

  • Description: Values returns all values in ascending order of key.

  • Format:

Values() []interface{}
  • Example:
func ExampleBTree_Values() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 6; i > 0; i-- {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      fmt.Println(tree.Values())

      // Output:
      // [val1 val2 val3 val4 val5 val6]
}

Map​

  • Description: Map returns all key/value pairs in the form of a map.

  • Format:

Map() map[interface{}]interface{}
  • Example:
func ExampleBTree_Map() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      fmt.Println(tree.Map())

      // Output:
      // map[key0:val0 key1:val1 key2:val2 key3:val3 key4:val4 key5:val5]
}

MapStrAny​

  • Description: MapStrAny returns all key/value pairs in the form of map[string]interface{}.

  • Format:

MapStrAny() map[string]interface{}
  • Example:
func ExampleBTree_MapStrAny() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set(1000+i, "val"+gconv.String(i))
      }

      fmt.Println(tree.MapStrAny())

      // Output:
      // map[1000:val0 1001:val1 1002:val2 1003:val3 1004:val4 1005:val5]
}

Clear​

  • Description: Clear deletes all data in the tree.

  • Format:

Clear()
  • Example:
func ExampleBTree_Clear() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set(1000+i, "val"+gconv.String(i))
      }
      fmt.Println(tree.Size())

      tree.Clear()
      fmt.Println(tree.Size())

      // Output:
      // 6
      // 0
}

Replace​

  • Description: Replace replaces the key/value in the tree with data of type map[interface{}]interface{}.

  • Format:

Replace(data map[interface{}]interface{})
  • Example:
func ExampleBTree_Replace() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      fmt.Println(tree.Map())

      data := map[interface{}]interface{}{
          "newKey0": "newVal0",
          "newKey1": "newVal1",
          "newKey2": "newVal2",
      }

      tree.Replace(data)

      fmt.Println(tree.Map())

      // Output:
      // map[key0:val0 key1:val1 key2:val2 key3:val3 key4:val4 key5:val5]
      // map[newKey0:newVal0 newKey1:newVal1 newKey2:newVal2]
}

Height​

  • Description: Height returns the height of the tree.

  • Format:

Height() int
  • Example:
func ExampleBTree_Height() {
      tree := gtree.NewBTree(3, gutil.ComparatorInt)
      for i := 0; i < 100; i++ {
          tree.Set(i, i)
      }
      fmt.Println(tree.Height())

      // Output:
      // 6
}

Left​

  • Description: Left returns the leftmost (smallest) node of type *BTreeEntry, or nil if the tree is empty.

  • Format:

Left() *BTreeEntry
  • Example:
func ExampleBTree_Left() {
      tree := gtree.NewBTree(3, gutil.ComparatorInt)
      for i := 1; i < 100; i++ {
          tree.Set(i, i)
      }
      fmt.Println(tree.Left().Key, tree.Left().Value)

      emptyTree := gtree.NewBTree(3, gutil.ComparatorInt)
      fmt.Println(emptyTree.Left())

      // Output:
      // 1 1
      // <nil>
}

  • Description: Right returns the rightmost (largest) node of type *BTreeEntry, or nil if the tree is empty.

  • Format:

Right() *BTreeEntry
  • Example:
func ExampleBTree_Right() {
      tree := gtree.NewBTree(3, gutil.ComparatorInt)
      for i := 1; i < 100; i++ {
          tree.Set(i, i)
      }
      fmt.Println(tree.Right().Key, tree.Right().Value)

      emptyTree := gtree.NewBTree(3, gutil.ComparatorInt)
      fmt.Println(emptyTree.Left())

      // Output:
      // 99 99
      // <nil>
}

String​

  • Description: String returns a display (for debugging) of the node in the tree.

  • Format:

String() string
  • Example:
func ExampleBTree_String() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      fmt.Println(tree.String())

      // Output:
      // key0
      // key1
      //     key2
      // key3
      //     key4
      //     key5
}

  • Description: Search searches the tree using the parameter key. If the key is found, it returns its corresponding key-value and returns the parameter found as true, otherwise false.

  • Format:

Search(key interface{}) (value interface{}, found bool)
  • Example:
func ExampleBTree_Search() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      fmt.Println(tree.Search("key0"))
      fmt.Println(tree.Search("key6"))

      // Output:
      // val0 true
      // <nil> false
}

Print​

  • Description: Print prints the tree to standard output.

  • Format:

Print()
  • Example:
func ExampleBTree_Print() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      tree.Print()

      // Output:
      // key0
      // key1
      //     key2
      // key3
      //     key4
      //     key5
}

Iterator​

  • Description: Iterator is equivalent to IteratorAsc.

  • Format:

Iterator(f func(key, value interface{}) bool)
  • Example:
func ExampleBTree_Iterator() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 10; i++ {
          tree.Set(i, 10-i)
      }

      var totalKey, totalValue int
      tree.Iterator(func(key, value interface{}) bool {
          totalKey += key.(int)
          totalValue += value.(int)

          return totalValue < 20
      })

      fmt.Println("totalKey:", totalKey)
      fmt.Println("totalValue:", totalValue)

      // Output:
      // totalKey: 3
      // totalValue: 27
}

IteratorFrom​

  • Description: IteratorFrom is equivalent to IteratorAscFrom.

  • Format:

IteratorFrom(key interface{}, match bool, f func(key, value interface{}) bool)
  • Example:
func ExampleBTree_IteratorFrom() {
      m := make(map[interface{}]interface{})
      for i := 1; i <= 5; i++ {
          m[i] = i * 10
      }
      tree := gtree.NewBTreeFrom(3, gutil.ComparatorInt, m)

      tree.IteratorFrom(1, true, func(key, value interface{}) bool {
          fmt.Println("key:", key, ", value:", value)
          return true
      })

      // Output:
      // key: 1 , value: 10
      // key: 2 , value: 20
      // key: 3 , value: 30
      // key: 4 , value: 40
      // key: 5 , value: 50
}

IteratorAsc​

  • Description: IteratorAsc iterates over the tree in ascending order using a custom callback function f in read-only mode. If f returns true, it continues iterating; if it returns false, it stops.

  • Format:

IteratorAsc(f func(key, value interface{}) bool)
  • Example:
func ExampleBTree_IteratorAsc() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 10; i++ {
          tree.Set(i, 10-i)
      }

      tree.IteratorAsc(func(key, value interface{}) bool {
          fmt.Println("key:", key, ", value:", value)
          return true
      })

      // Output:
      // key: 0 , value: 10
      // key: 1 , value: 9
      // key: 2 , value: 8
      // key: 3 , value: 7
      // key: 4 , value: 6
      // key: 5 , value: 5
      // key: 6 , value: 4
      // key: 7 , value: 3
      // key: 8 , value: 2
      // key: 9 , value: 1
}

IteratorAscFrom​

  • Description: IteratorAscFrom iterates over the tree in ascending order using a custom callback function f in read-only mode. The parameter key specifies from which key to start iterating. When match is true, iteration starts from the complete match of key; otherwise, iteration uses index searching. If f returns true, it continues iterating; if it returns false, it stops.

  • Format:

IteratorAscFrom(key interface{}, match bool, f func(key, value interface{}) bool)
  • Example:
func ExampleBTree_IteratorAscFrom_Normal() {
      m := make(map[interface{}]interface{})
      for i := 1; i <= 5; i++ {
          m[i] = i * 10
      }
      tree := gtree.NewBTreeFrom(3, gutil.ComparatorInt, m)

      tree.IteratorAscFrom(1, true, func(key, value interface{}) bool {
          fmt.Println("key:", key, ", value:", value)
          return true
      })

      // Output:
      // key: 1 , value: 10
      // key: 2 , value: 20
      // key: 3 , value: 30
      // key: 4 , value: 40
      // key: 5 , value: 50
}
func ExampleBTree_IteratorAscFrom_NoExistKey() {
      m := make(map[interface{}]interface{})
      for i := 1; i <= 5; i++ {
          m[i] = i * 10
      }
      tree := gtree.NewBTreeFrom(3, gutil.ComparatorInt, m)

      tree.IteratorAscFrom(0, true, func(key, value interface{}) bool {
          fmt.Println("key:", key, ", value:", value)
          return true
      })

      // Output:
}
func ExampleBTree_IteratorAscFrom_NoExistKeyAndMatchFalse() {
      m := make(map[interface{}]interface{})
      for i := 1; i <= 5; i++ {
          m[i] = i * 10
      }
      tree := gtree.NewBTreeFrom(3, gutil.ComparatorInt, m)

      tree.IteratorAscFrom(0, false, func(key, value interface{}) bool {
          fmt.Println("key:", key, ", value:", value)
          return true
      })

      // Output:
      // key: 1 , value: 10
      // key: 2 , value: 20
      // key: 3 , value: 30
      // key: 4 , value: 40
      // key: 5 , value: 50
}

IteratorDesc​

  • Description: IteratorDesc iterates over the tree in descending order using a custom callback function f in read-only mode. If f returns true, it continues iterating; if it returns false, it stops.

  • Format:

IteratorDesc(f func(key, value interface{}) bool)
  • Example:
func ExampleBTree_IteratorDesc() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 10; i++ {
          tree.Set(i, 10-i)
      }

      tree.IteratorDesc(func(key, value interface{}) bool {
          fmt.Println("key:", key, ", value:", value)
          return true
      })

      // Output:
      // key: 9 , value: 1
      // key: 8 , value: 2
      // key: 7 , value: 3
      // key: 6 , value: 4
      // key: 5 , value: 5
      // key: 4 , value: 6
      // key: 3 , value: 7
      // key: 2 , value: 8
      // key: 1 , value: 9
      // key: 0 , value: 10
}

IteratorDescFrom​

  • Description: IteratorDescFrom iterates over the tree in descending order using a custom callback function f in read-only mode. The parameter key specifies from which key to start iterating. When match is true, iteration starts from the complete match of key; otherwise, iteration uses index searching. If f returns true, it continues iterating; if it returns false, it stops.

  • Format:

IteratorDescFrom(key interface{}, match bool, f func(key, value interface{}) bool)
  • Example:
func ExampleBTree_IteratorDescFrom() {
      m := make(map[interface{}]interface{})
      for i := 1; i <= 5; i++ {
          m[i] = i * 10
      }
      tree := gtree.NewBTreeFrom(3, gutil.ComparatorInt, m)

      tree.IteratorDescFrom(5, true, func(key, value interface{}) bool {
          fmt.Println("key:", key, ", value:", value)
          return true
      })

      // Output:
      // key: 5 , value: 50
      // key: 4 , value: 40
      // key: 3 , value: 30
      // key: 2 , value: 20
      // key: 1 , value: 10
}

MarshalJson​

  • Description: MarshalJSON implements the json.Marshal interface.

  • Format:

MarshalJSON() ([]byte, error)
  • Example:
func ExampleBTree_MarshalJSON() {
      tree := gtree.NewBTree(3, gutil.ComparatorString)
      for i := 0; i < 6; i++ {
          tree.Set("key"+gconv.String(i), "val"+gconv.String(i))
      }

      bytes, err := json.Marshal(tree)
      if err == nil {
          fmt.Println(gconv.String(bytes))
      }

      // Output:
      // {"key0":"val0","key1":"val1","key2":"val2","key3":"val3","key4":"val4","key5":"val5"}
}