Guava – IntMath.checkedSubtract()方法及实例
checkedSubtract(int a, int b)是Guava的IntMath类的一个方法,接受两个参数 a and b ,并返回它们的差值。
语法:
public static int checkedSubtract(int a, int b)
参数: 该方法接受两个int值a和b,并计算它们的差异。
返回值: 该方法返回传递给它的int值的差值,只要它不溢出。
异常情况: CheckedSubtract(int a, int b)方法如果差值即(a – b)在有符号int算术中溢出,则抛出ArithmeticException。
下面的例子说明了上述方法的实现。
例1:
// Java code to show implementation of
// checkedSubtract(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 checkedSubtract(int a, int b)
// method of Guava's IntMath class
int ans1 = IntMath.checkedSubtract(a1, b1);
System.out.println("Difference of " + a1 + " and "
+ b1 + " is: " + ans1);
int a2 = 150;
int b2 = 667;
// Using checkedSubtract(int a, int b)
// method of Guava's IntMath class
int ans2 = IntMath.checkedSubtract(a2, b2);
System.out.println("Difference of " + a2 + " and "
+ b2 + " is: " + ans2);
}
}
输出:
Difference of 25 and 36 is: -11
Difference of 150 and 667 is: -517
例2:
// Java code to show implementation of
// checkedSubtract(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 checkedSubtract(int a, int b) method
// of Guava's IntMath class
// This should throw "ArithmeticException"
// as the difference overflows in signed
// int arithmetic
int ans = IntMath.checkedSubtract(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
参考资料:
https://google.github.io/guava/releases/20.0/api/docs/com/google/common/math/IntMath.html#checkedSubtract-int-int-