src/share/classes/java/lang/Math.java

rev 7819 : 8022109: Evaluate adding incrementExact, decrementExact, negateExact to java.lang.Math
Summary: Add the methods for parameter types int and long.
Reviewed-by: TBD
Contributed-by: Brian Burkhalter <brian.burkhalter@oracle.com>

*** 823,833 ****
       * @since 1.8
       */
      public static int multiplyExact(int x, int y) {
          long r = (long)x * (long)y;
          if ((int)r != r) {
!             throw new ArithmeticException("long overflow");
          }
          return (int)r;
      }
  
      /**
--- 823,833 ----
       * @since 1.8
       */
      public static int multiplyExact(int x, int y) {
          long r = (long)x * (long)y;
          if ((int)r != r) {
!             throw new ArithmeticException("integer overflow");
          }
          return (int)r;
      }
  
      /**
*** 855,864 ****
--- 855,966 ----
          }
          return r;
      }
  
      /**
+      * Returns the argument incremented by one, throwing an exception if the
+      * result overflows an {@code int}.
+      * 
+      * @param a the value to increment
+      * @return the result
+      * @throws ArithmeticException if the result overflows an int
+      * @since 1.8
+      */
+     public static int incrementExact(int a) {
+         if (a == Integer.MAX_VALUE) {
+             throw new ArithmeticException("integer overflow");
+         }
+ 
+         return a + 1;
+     }
+ 
+     /**
+      * Returns the argument incremented by one, throwing an exception if the
+      * result overflows a {@code long}.
+      * 
+      * @param a the value to increment
+      * @return the result
+      * @throws ArithmeticException if the result overflows a long
+      * @since 1.8
+      */
+     public static long incrementExact(long a) {
+         if (a == Long.MAX_VALUE) {
+             throw new ArithmeticException("long overflow");
+         }
+ 
+         return a + 1L;
+     }
+ 
+     /**
+      * Returns the argument decremented by one, throwing an exception if the
+      * result overflows an {@code int}.
+      * 
+      * @param a the value to decrement
+      * @return the result
+      * @throws ArithmeticException if the result overflows an int
+      * @since 1.8
+      */
+     public static int decrementExact(int a) {
+         if (a == Integer.MIN_VALUE) {
+             throw new ArithmeticException("integer overflow");
+         }
+ 
+         return a - 1;
+     }
+ 
+     /**
+      * Returns the argument decremented by one, throwing an exception if the
+      * result overflows a {@code long}.
+      * 
+      * @param a the value to decrement
+      * @return the result
+      * @throws ArithmeticException if the result overflows a long
+      * @since 1.8
+      */
+     public static long decrementExact(long a) {
+         if (a == Long.MIN_VALUE) {
+             throw new ArithmeticException("long overflow");
+         }
+ 
+         return a - 1L;
+     }
+ 
+     /**
+      * Returns the negation of the argument, throwing an exception if the
+      * result overflows an {@code int}.
+      * 
+      * @param a the value to negate
+      * @return the result
+      * @throws ArithmeticException if the result overflows an int
+      * @since 1.8
+      */
+     public static int negateExact(int a) {
+         if (a == Integer.MIN_VALUE) {
+             throw new ArithmeticException("integer overflow");
+         }
+ 
+         return -a;
+     }
+ 
+     /**
+      * Returns the negation of the argument, throwing an exception if the
+      * result overflows a {@code long}.
+      * 
+      * @param a the value to negate
+      * @return the result
+      * @throws ArithmeticException if the result overflows a long
+      * @since 1.8
+      */
+     public static long negateExact(long a) {
+         if (a == Long.MIN_VALUE) {
+             throw new ArithmeticException("long overflow");
+         }
+ 
+         return -a;
+     }
+ 
+     /**
       * Returns the value of the {@code long} argument;
       * throwing an exception if the value overflows an {@code int}.
       *
       * @param value the long value
       * @return the argument as an int