Java番石榴 | IntMath.checkedMultiply(int a, int b) 方法与示例
checkedMultiply(int a, int b)是 Guava 的 IntMath 类的一个方法,它接受两个参数a和b ,并返回它们的乘积。
句法:
public static int checkedMultiply(int a, int b)
参数:该方法接受两个 int 值a和b并计算它们的乘积。
返回值:该方法返回传递给它的 int 值的乘积,前提是它不会溢出。
例外:如果乘积(即 (a – b) 在有符号 int 算术中溢出),方法 checkedMultiply(int a, int b) 将引发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
// checkedMultiply(int a, int b) method
// of Guava's IntMath class
import java.math.RoundingMode;
import com.google.common.math.IntMath;
class GFG {
// Driver code
public static void main(String args[])
{
int a1 = 25;
int b1 = 36;
// Using checkedMultiply(int a, int b)
// method of Guava's IntMath class
int ans1 = IntMath.checkedMultiply(a1, b1);
System.out.println("Product of " + a1 + " and "
+ b1 + " is: " + ans1);
int a2 = 150;
int b2 = 667;
// Using checkedMultiply(int a, int b)
// method of Guava's IntMath class
int ans2 = IntMath.checkedMultiply(a2, b2);
System.out.println("Product of " + a2 + " and "
+ b2 + " is: " + ans2);
}
}
输出:
Product of 25 and 36 is: 900
Product of 150 and 667 is: 100050
示例 2:
// Java code to show implementation of
// checkedMultiply(int a, int b) method
// of Guava's IntMath class
import java.math.RoundingMode;
import com.google.common.math.IntMath;
class GFG {
static int findDiff(int a, int b)
{
try {
// Using checkedMultiply(int a, int b) method
// of Guava's IntMath class
// This should throw "ArithmeticException"
// as the product overflows in signed
// int arithmetic
int ans = IntMath.checkedMultiply(a, b);
// Return the answer
return ans;
}
catch (Exception e) {
System.out.println(e);
return -1;
}
}
// Driver code
public static void main(String args[])
{
int a = Integer.MIN_VALUE;
int b = 452;
try {
// Function calling
findDiff(a, b);
}
catch (Exception e) {
System.out.println(e);
}
}
}
输出:
java.lang.ArithmeticException: overflow
参考: https://google.github.io/guava/releases/20.0/api/docs/com/google/common/math/IntMath.html#checkedMultiply-int-int-