Java 中的 Ints 类
java 8object oriented programmingprogramming
Ints 类是用于原始类型 int 的实用类。让我们看一下类声明 −
@GwtCompatible public final class Ints extends Object
示例
让我们看一个执行连接方法的示例。Ints 类中的 concat() 函数用于连接作为参数传递的数组。 −
import com.google.common.primitives.Ints;
import java.util.*;
class Demo {
public static void main(String[] args) {
int[] myArr1 = { 100, 150, 230, 300, 400 };
int[] myArr2 = { 450, 550, 700, 800, 1000 };
System.out.println("Array 1 = ");
for(int i=0; i < myArr1.length; i++) {
System.out.println(myArr1[i]);
}
System.out.println("Array 2 = ");
for(int i=0; i < myArr2.length; i++) {
System.out.println(myArr2[i]);
}
int[] arr = Ints.concat(myArr1, myArr2);
System.out.println("Concatenated arrays = "+Arrays.toString(arr));
}
}
输出
Array 1 = 100 150 230 300 400 Array 2 = 450 550 700 800 1000 Concatenated arrays = [100, 150, 230, 300, 400, 450, 550, 700, 800, 1000]
示例
让我们看另一个例子 −
import java.util.List;
import com.google.common.primitives.Ints;
public class GuavaTester {
public static void main(String args[]) {
GuavaTester tester = new GuavaTester();
tester.testInts();
}
private void testInts() {
int[] intArray = {1,2,3,4,5,6,7,8,9};
//将原始类型数组转换为对象数组
List<Integer> objectArray = Ints.asList(intArray);
System.out.println(objectArray.toString());
//将对象数组转换为原始类型数组
intArray = Ints.toArray(objectArray);
System.out.print("[ ");
for(int i = 0; i < intArray.length ; i++) {
System.out.print(intArray[i] + " ");
}
System.out.println("] ");
//检查元素是否存在于原始值列表中
System.out.println("5 is in list? " + Ints.contains(intArray, 5));
//返回最小值
System.out.println("Min: " + Ints.min(intArray));
//返回最大值
System.out.println("Max: " + Ints.max(intArray));
//从整数获取字节数组
byte[] byteArray = Ints.toByteArray(20000);
for(int i = 0; i < byteArray.length ; i++) {
System.out.print(byteArray[i] + " ");
}
}
}
输出
[1, 2, 3, 4, 5, 6, 7, 8, 9] [ 1 2 3 4 5 6 7 8 9 ] 5 is in list? true Min: 1 Max: 9 0 0 78 32
