Guava Doubles 类

Doubles 是一个用于处理原始类型 double 的实用工具类。

类声明

下面是 com.google.common.primitives.Doubles 类的声明 − com.google.common.primitives.Doubles 类 –

@GwtCompatible(emulated = true)
   public final class Doubles
      extends Object

字段

方法

继承的方法

这个类继承了以下类的方法：

• java.lang.Object

Double类的示例

使用任意文本编辑器在例如C:/> Guava中创建以下Java程序：

GuavaTester.java

import java.util.List;

import com.google.common.primitives.Doubles;

public class GuavaTester {

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

   private void testDoubles() {
      double[] doubleArray = {1.0,2.0,3.0,4.0,5.0,6.0,7.0,8.0,9.0};

      //convert array of primitives to array of objects
      List<Double> objectArray = Doubles.asList(doubleArray);
      System.out.println(objectArray.toString());

      //convert array of objects to array of primitives
      doubleArray = Doubles.toArray(objectArray);
      System.out.print("[ ");

      for(int i = 0; i< doubleArray.length ; i++) {
         System.out.print(doubleArray[i] + " ");
      }

      System.out.println("]");

      //check if element is present in the list of primitives or not
      System.out.println("5.0 is in list? " + Doubles.contains(doubleArray, 5.0f));

      //return the index of element
      System.out.println("5.0 position in list " + Doubles.indexOf(doubleArray, 5.0f));

      //Returns the minimum     
      System.out.println("Min: " + Doubles.min(doubleArray));

      //Returns the maximum     
      System.out.println("Max: " + Doubles.max(doubleArray));   
   }
}

验证结果

使用 javac 编译器编译该类，如下：

C:\Guava>javac GuavaTester.java

现在运行GuavaTester以查看结果。

C:\Guava>java GuavaTester

看看结果。

[1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0]
[ 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 ]
5.0 is in list? true
5.0 position in list 4
Min: 1.0
Max: 9.0