This is an automated email from the ASF dual-hosted git repository.
sebb pushed a commit to branch java8-simplify
in repository https://gitbox.apache.org/repos/asf/commons-numbers.git
commit 2f60d424725ca619abf324858593368e66dd5fc2
Author: Sebb <s...@apache.org>
AuthorDate: Sun Dec 24 13:20:13 2023 +0000
Use Java 1.8 methods to simplify the ArithmeticUtils methods
remainderUnsigned and divideUnsigned (both int and long)
---
.../commons/numbers/core/ArithmeticUtils.java | 68 +++-------------------
src/changes/changes.xml | 3 +
2 files changed, 11 insertions(+), 60 deletions(-)
diff --git
a/commons-numbers-core/src/main/java/org/apache/commons/numbers/core/ArithmeticUtils.java
b/commons-numbers-core/src/main/java/org/apache/commons/numbers/core/ArithmeticUtils.java
index d34d7e2b..7afde103 100644
---
a/commons-numbers-core/src/main/java/org/apache/commons/numbers/core/ArithmeticUtils.java
+++
b/commons-numbers-core/src/main/java/org/apache/commons/numbers/core/ArithmeticUtils.java
@@ -470,7 +470,7 @@ public final class ArithmeticUtils {
* Returns the unsigned remainder from dividing the first argument
* by the second where each argument and the result is interpreted
* as an unsigned value.
- * <p>This method does not use the {@code long} datatype.</p>
+ * <p>This method uses the Java 1.8+ method {@link
Integer#remainderUnsigned(int, int)}.</p>
*
* @param dividend the value to be divided
* @param divisor the value doing the dividing
@@ -478,27 +478,14 @@ public final class ArithmeticUtils {
* the second argument.
*/
public static int remainderUnsigned(int dividend, int divisor) {
- if (divisor >= 0) {
- if (dividend >= 0) {
- return dividend % divisor;
- }
- // The implementation is a Java port of algorithm described in the
book
- // "Hacker's Delight" (section "Unsigned short division from
signed division").
- final int q = ((dividend >>> 1) / divisor) << 1;
- dividend -= q * divisor;
- if (dividend < 0 || dividend >= divisor) {
- dividend -= divisor;
- }
- return dividend;
- }
- return dividend >= 0 || dividend < divisor ? dividend : dividend -
divisor;
+ return Integer.remainderUnsigned(dividend, divisor);
}
/**
* Returns the unsigned remainder from dividing the first argument
* by the second where each argument and the result is interpreted
* as an unsigned value.
- * <p>This method does not use the {@code BigInteger} datatype.</p>
+ * <p>This method uses the Java 1.8+ method {@link
Long#remainderUnsigned(int, int)}.</p>
*
* @param dividend the value to be divided
* @param divisor the value doing the dividing
@@ -506,20 +493,7 @@ public final class ArithmeticUtils {
* the second argument.
*/
public static long remainderUnsigned(long dividend, long divisor) {
- if (divisor >= 0L) {
- if (dividend >= 0L) {
- return dividend % divisor;
- }
- // The implementation is a Java port of algorithm described in the
book
- // "Hacker's Delight" (section "Unsigned short division from
signed division").
- final long q = ((dividend >>> 1) / divisor) << 1;
- dividend -= q * divisor;
- if (dividend < 0L || dividend >= divisor) {
- dividend -= divisor;
- }
- return dividend;
- }
- return dividend >= 0L || dividend < divisor ? dividend : dividend -
divisor;
+ return Long.remainderUnsigned(dividend, divisor);
}
/**
@@ -531,7 +505,7 @@ public final class ArithmeticUtils {
* bit-wise identical if the two operands are regarded as both
* being signed or both being unsigned. Therefore separate {@code
* addUnsigned}, etc. methods are not provided.</p>
- * <p>This method does not use the {@code long} datatype.</p>
+ * <p>This method uses the Java 1.8+ method {@link
Integer#divideUnsigned(int, int)}.</p>
*
* @param dividend the value to be divided
* @param divisor the value doing the dividing
@@ -539,20 +513,7 @@ public final class ArithmeticUtils {
* the second argument
*/
public static int divideUnsigned(int dividend, int divisor) {
- if (divisor >= 0) {
- if (dividend >= 0) {
- return dividend / divisor;
- }
- // The implementation is a Java port of algorithm described in the
book
- // "Hacker's Delight" (section "Unsigned short division from
signed division").
- int q = ((dividend >>> 1) / divisor) << 1;
- dividend -= q * divisor;
- if (dividend < 0L || dividend >= divisor) {
- q++;
- }
- return q;
- }
- return dividend >= 0 || dividend < divisor ? 0 : 1;
+ return Integer.divideUnsigned(dividend, divisor);
}
/**
@@ -564,7 +525,7 @@ public final class ArithmeticUtils {
* bit-wise identical if the two operands are regarded as both
* being signed or both being unsigned. Therefore separate {@code
* addUnsigned}, etc. methods are not provided.</p>
- * <p>This method does not use the {@code BigInteger} datatype.</p>
+ * <p>This method uses the Java 1.8+ method {@link
Long#divideUnsigned(int, int)}.</p>
*
* @param dividend the value to be divided
* @param divisor the value doing the dividing
@@ -572,20 +533,7 @@ public final class ArithmeticUtils {
* the second argument.
*/
public static long divideUnsigned(long dividend, long divisor) {
- if (divisor >= 0L) {
- if (dividend >= 0L) {
- return dividend / divisor;
- }
- // The implementation is a Java port of algorithm described in the
book
- // "Hacker's Delight" (section "Unsigned short division from
signed division").
- long q = ((dividend >>> 1) / divisor) << 1;
- dividend -= q * divisor;
- if (dividend < 0L || dividend >= divisor) {
- q++;
- }
- return q;
- }
- return dividend >= 0L || dividend < divisor ? 0L : 1L;
+ return Long.divideUnsigned(dividend, divisor);
}
/**
diff --git a/src/changes/changes.xml b/src/changes/changes.xml
index d9b796b2..c9e96a1f 100644
--- a/src/changes/changes.xml
+++ b/src/changes/changes.xml
@@ -56,6 +56,9 @@ If the output is not quite correct, check for invisible
trailing spaces!
<release version="1.2" date="TBD" description="
New features, updates and bug fixes.
">
+ <action dev="sebb" type="update">
+ Use Java 1.8 methods to simplify the ArithmeticUtils methods
remainderUnsigned and divideUnsigned (both int and long)
+ </action>
<action dev="aherbert" type="add" due-to="Harald Kirsch"
issue="NUMBERS-205">
"Addition/Multiplication": Introduces isZero to Addition and isOne to
Multiplication
interfaces. Override the default implementation in implementing
classes to avoid
