Guava – LongMath.checkedAdd方法与实例
CheckedAdd(long a, long b)是Guava的LongMath类的一个方法,它接受两个参数 a 和b ,并返回它们的和。
语法:
public static long checkedAdd(long a, long b)
参数: 该方法接受两个长值a和b并计算它们的总和。
返回值: 该方法返回传递给它的长值的总和,只要它不溢出。
异常情况: 如果总和即(a – b)在有符号长运算中溢出,方法checkedAdd(long a, long b)会抛出ArithmeticException。
下面的例子说明了上述方法的实现。
示例1:
// Java code to show implementation of
// checkedAdd(long a, long b) method
// of Guava's LongMath class
import java.math.RoundingMode;
import com.google.common.math.LongMath;
class GFG {
// Driver code
public static void main(String args[])
{
long a1 = 25;
long b1 = 36;
// Using checkedAdd(long a, long b)
// method of Guava's LongMath class
long ans1 = LongMath.checkedAdd(a1, b1);
System.out.println("Sum of " + a1 + " and "
+ b1 + " is: " + ans1);
long a2 = 150;
long b2 = 667;
// Using checkedAdd(long a, long b)
// method of Guava's LongMath class
long ans2 = LongMath.checkedAdd(a2, b2);
System.out.println("Sum of " + a2 + " and "
+ b2 + " is: " + ans2);
}
}
输出:
Sum of 25 and 36 is: 61
Sum of 150 and 667 is: 817
示例2:
// Java code to show implementation of
// checkedAdd(long a, long b) method
// of Guava's LongMath class
import java.math.RoundingMode;
import com.google.common.math.LongMath;
class GFG {
static long findDiff(long a, long b)
{
try {
// Using checkedAdd(long a, long b) method
// of Guava's LongMath class
// This should throw "ArithmeticException"
// as the sum overflows in signed
// long arithmetic
long ans = LongMath.checkedAdd(a, b);
// Return the answer
return ans;
}
catch (Exception e) {
System.out.println(e);
return -1;
}
}
// Driver code
public static void main(String args[])
{
long a = Long.MIN_VALUE;
long b = 452;
try {
// Function calling
findDiff(a, b);
}
catch (Exception e) {
System.out.println(e);
}
}
}
输出:
参考资料:
https://google.github.io/guava/releases/20.0/api/docs/com/google/common/math/LongMath.html#checkedAdd-long-long-