Java Guava Doubles.lastIndexOf()用法及代码示例

Guava库中Doubles类的lastIndexOf()方法用于在double数组中查找给定double值的最后一个索引。要搜索的double值和要在其中搜索double的double数组均作为参数传递给此方法。它返回一个整数值，该整数值是指定的double值的最后一个索引。如果找不到该值，则返回-1。

用法:

public static int lastIndexOf(double[] array,
                              double target)

参数：此方法接受两个强制性参数：

array:这是要在其中搜索double值的double值的数组。
target:要在double数组中查找最后一个索引的double值。

返回值：此方法返回一个整数值，该整数值是指定的double值的最后一个索引。如果找不到该值，则返回-1。

下面的程序演示了此方法：

范例1：

// Java code to show implementation of 
// Guava's Doubles.lastIndexOf() method 
  
import com.google.common.primitives.Doubles; 
import java.util.Arrays; 
  
class GFG { 
  
    // Driver's code 
    public static void main(String[] args) 
    { 
  
        // Creating a double array 
        double[] arr = { 1.2, 2.2, 3.2, 4.2, 
                         3.2, 5.6, 3.2, 4.4 }; 
  
        double target = 3.2; 
  
        // Using Doubles.lastIndexOf() method 
        // to get the index of last appearance 
        // of a given element in array 
        // and return -1 if element is 
        // not found in the array 
        int index 
            = Doubles.lastIndexOf(arr, target); 
  
        if (index != -1) { 
            System.out.println("Target is present"
                               + " at index "
                               + index); 
        } 
        else { 
            System.out.println("Target is not present"
                               + " in the array"); 
        } 
    } 
}

输出：

Target is present at index 6

范例2：

// Java code to show implementation of 
// Guava's Doubles.lastIndexOf() method 
  
import com.google.common.primitives.Doubles; 
import java.util.Arrays; 
  
class GFG { 
  
    // Driver's code 
    public static void main(String[] args) 
    { 
        // Creating a double array 
        double[] arr = { 1.2, 2.2, 3.2, 4.2, 
                         3.2, 5.6, 3.2, 4.4 }; 
  
        double target = 10.2; 
  
        // Using Doubles.lastIndexOf() method 
        // to get the index of last appearance 
        // of a given element in array 
        // and return -1 if element is 
        // not found in the array 
        int index 
            = Doubles.lastIndexOf(arr, target); 
  
        if (index != -1) { 
            System.out.println("Target is present"
                               + " at index "
                               + index); 
        } 
        else { 
            System.out.println("Target is not present"
                               + " in the array"); 
        } 
    } 
}

输出：

Target is not present in the array

参考： https://google.github.io/guava/releases/19.0/api/docs/com/google/common/primitives/Doubles.html#lastIndexOf(double[], %20double)

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注：本文由纯净天空筛选整理自Sahil_Bansall大神的英文原创作品 Java Guava | Doubles.lastIndexOf() method with Examples。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。