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📜  Guava-范围类

📅  最后修改于: 2020-11-16 06:52:50             🧑  作者: Mango

范围表示间隔或序列。它用于获取位于特定范围内的一组数字/字符串。

类声明

以下是com.google.common.collect.Range 类的声明-

@GwtCompatible
public final class Range
   extends Object
      implements Predicate, Serializable

方法

Sr.No Method & Description
1

static > Range all()

Returns a range that contains every value of type C.
2

boolean apply(C input)Deprecated.

Provided only to satisfy the Predicate interface; use contains(C) instead.
3

static > Range atLeast(C endpoint)

Returns a range that contains all values greater than or equal to endpoint.
4

static > Range atMost(C endpoint)

Returns a range that contains all values less than or equal to endpoint.
5

Range canonical(DiscreteDomain domain)

Returns the canonical form of this range in the given domain.
6

static > Range closed(C lower, C upper)

Returns a range that contains all values greater than or equal to lower and less than or equal to upper.
7

static > Range closedOpen(C lower, C upper)

Returns a range that contains all values greater than or equal to lower and strictly less than upper.
8

boolean contains(C value)

Returns true if value is within the bounds of this range.
9

boolean containsAll(Iterable values)

Returns true if every element in values is contained in this range.
10

static > Range downTo(C endpoint, BoundType boundType)

Returns a range from the given endpoint, which may be either inclusive (closed) or exclusive (open), with no upper bound.
11

static > Range encloseAll(Iterable values)

Returns the minimal range that contains all of the given values.
12

boolean encloses(Range other)

Returns true if the bounds of other do not extend outside the bounds of this range.
13

boolean equals(Object object)

Returns true if object is a range having the same endpoints and bound types as this range.
14

static > Range greaterThan(C endpoint)

Returns a range that contains all values strictly greater than endpoint.
15

int hashCode()

Returns a hash code for this range.
16

boolean hasLowerBound()

Returns true if this range has a lower endpoint.
17

boolean hasUpperBound()

Returns true if this range has an upper endpoint.
18

Range intersection(Range connectedRange)

Returns the maximal range enclosed by both this range and connectedRange, if such a range exists.
19

boolean isConnected(Range other)

Returns true if there exists a (possibly empty) range which is enclosed by both this range and other.
20

boolean isEmpty()

Returns true if this range is of the form [v..v) or (v..v].
21

static > Range lessThan(C endpoint)

Returns a range that contains all values strictly less than endpoint.
22

BoundType lowerBoundType()

Returns the type of this range’s lower bound: BoundType.CLOSED if the range includes its lower endpoint, BoundType.OPEN if it does not.
23

C lowerEndpoint()

Returns the lower endpoint of this range.
24

static > Range open(C lower, C upper)

Returns a range that contains all values strictly greater than lower and strictly less than upper.
25

static > Range openClosed(C lower, C upper)

Returns a range that contains all values strictly greater than lower and less than or equal to upper.
26

static > Range range(C lower, BoundType lowerType, C upper, BoundType upperType)

Returns a range that contains any value from lower to upper, where each endpoint may be either inclusive (closed) or exclusive (open).
27

static > Range singleton(C value)

Returns a range that contains only the given value.
28

Range span(Range other)

Returns the minimal range that encloses both this range and other.
29

String toString()

Returns a string representation of this range, such as “[3..5)” (other examples are listed in the class documentation).
30

BoundType upperBoundType()

Returns the type of this range’s upper bound: BoundType.CLOSED if the range includes its upper endpoint, BoundType.OPEN if it does not.
31

C upperEndpoint()

Returns the upper endpoint of this range.
32

static > Range upTo(C endpoint, BoundType boundType)

Returns a range with no lower bound up to the given endpoint, which may be either inclusive (closed) or exclusive (open).

继承的方法

此类从以下类继承方法-

  • java.lang.Object

范围类别的例子

使用您选择的任何编辑器在C：/> Guava中创建以下Java程序。

GuavaTester.java

import com.google.common.collect.ContiguousSet;
import com.google.common.collect.DiscreteDomain;
import com.google.common.collect.Range;
import com.google.common.primitives.Ints;

public class GuavaTester {

   public static void main(String args[]) {
      GuavaTester tester = new GuavaTester();
      tester.testRange();
   }

   private void testRange() {

      //create a range [a,b] = { x | a <= x <= b}
      Range range1 = Range.closed(0, 9);    
      System.out.print("[0,9] : ");
      printRange(range1);        
      
      System.out.println("5 is present: " + range1.contains(5));
      System.out.println("(1,2,3) is present: " + range1.containsAll(Ints.asList(1, 2, 3)));
      System.out.println("Lower Bound: " + range1.lowerEndpoint());
      System.out.println("Upper Bound: " + range1.upperEndpoint());

      //create a range (a,b) = { x | a < x < b}
      Range range2 = Range.open(0, 9);
      System.out.print("(0,9) : ");
      printRange(range2);

      //create a range (a,b] = { x | a < x <= b}
      Range range3 = Range.openClosed(0, 9);
      System.out.print("(0,9] : ");
      printRange(range3);

      //create a range [a,b) = { x | a <= x < b}
      Range range4 = Range.closedOpen(0, 9);
      System.out.print("[0,9) : ");
      printRange(range4);

      //create an open ended range (9, infinity
      Range range5 = Range.greaterThan(9);
      System.out.println("(9,infinity) : ");
      System.out.println("Lower Bound: " + range5.lowerEndpoint());
      System.out.println("Upper Bound present: " + range5.hasUpperBound());

      Range range6 = Range.closed(3, 5);    
      printRange(range6);

      //check a subrange [3,5] in [0,9]
      System.out.println("[0,9] encloses [3,5]:" + range1.encloses(range6));

      Range range7 = Range.closed(9, 20);    
      printRange(range7);
      
      //check ranges to be connected        
      System.out.println("[0,9] is connected [9,20]:" + range1.isConnected(range7));
      Range range8 = Range.closed(5, 15);    

      //intersection
      printRange(range1.intersection(range8));

      //span
      printRange(range1.span(range8));
   }

   private void printRange(Range range) {        
   
      System.out.print("[ ");
      
      for(int grade : ContiguousSet.create(range, DiscreteDomain.integers())) {
         System.out.print(grade +" ");
      }
      System.out.println("]");
   }
}

验证结果

使用javac编译器编译类，如下所示：

C:\Guava>javac GuavaTester.java

现在运行GuavaTester以查看结果。

C:\Guava>java GuavaTester

查看结果。

[0,9] : [ 0 1 2 3 4 5 6 7 8 9 ]
5 is present: true
(1,2,3) is present: true
Lower Bound: 0
Upper Bound: 9
(0,9) : [ 1 2 3 4 5 6 7 8 ]
(0,9] : [ 1 2 3 4 5 6 7 8 9 ]
[0,9) : [ 0 1 2 3 4 5 6 7 8 ]
(9,infinity) : 
Lower Bound: 9
Upper Bound present: false
[ 3 4 5 ]
[0,9] encloses [3,5]:true
[ 9 10 11 12 13 14 15 16 17 18 19 20 ]
[0,9] is connected [9,20]:true
[ 5 6 7 8 9 ]
[ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 ]