Guava – Range 类

Range代表一个区间或一个序列。它被用来获得一组位于特定范围内的数字/字符串.

Range 类声明

以下是com.google.common.collection.Range <C>类的声明 −

@GwtCompatiblepublic final class Range<C extends Comparable>   extends Object      implements Predicate<C>, Serializable

Range 类函数

Range 类继承

该类继承了以下类的方法 −

Range 类示例

在C:/ >Guava中使用你选择的任何编辑器创建以下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<Integer> 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<Integer> range2 = Range.open(0, 9);      System.out.print("(0,9) : ");      printRange(range2);      //create a range (a,b] = { x | a < x <= b}      Range<Integer> range3 = Range.openClosed(0, 9);      System.out.print("(0,9] : ");      printRange(range3);      //create a range [a,b) = { x | a <= x < b}      Range<Integer> range4 = Range.closedOpen(0, 9);      System.out.print("[0,9) : ");      printRange(range4);      //create an open ended range (9, infinity      Range<Integer> 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<Integer> 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<Integer> 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<Integer> range8 = Range.closed(5, 15);        //intersection      printRange(range1.intersection(range8));      //span      printRange(range1.span(range8));   }   private void printRange(Range<Integer> range) {            System.out.print("[ ");      for(int grade : ContiguousSet.create(range, DiscreteDomain.integers())) {         System.out.print(grade +" ");      }      System.out.println("]");   }}

Range 类验证结果

使用javac编译器编译该类，如下所示 −

C:\Guava>javac GuavaTester.java

现在运行GuavaTester来看看结果.

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: trueLower Bound: 0Upper 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: 9Upper 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 ]