apache · handsomewu6688-design · May 19, 2026
diff --git a/...ples/examples-sofm/tsp/src/main/java/org/apache/commons/math4/examples/sofm/tsp/City.java b/...ples/examples-sofm/tsp/src/main/java/org/apache/commons/math4/examples/sofm/tsp/City.java
@@ -155,8 +155,7 @@ public static Set<City> unique(City[] cities) {
     /** {@inheritDoc} */
     @Override
     public boolean equals(Object o) {
-        if (o instanceof City) {
-            final City other = (City) o;
+        if (o instanceof City other) {
             return x == other.x &&
                 y == other.y;
         }

diff --git a/commons-math-legacy-core/src/main/java/org/apache/commons/math4/legacy/core/dfp/Dfp.java b/commons-math-legacy-core/src/main/java/org/apache/commons/math4/legacy/core/dfp/Dfp.java
@@ -894,8 +894,7 @@ public boolean isZero() {
     @Override
     public boolean equals(final Object other) {
 
-        if (other instanceof Dfp) {
-            final Dfp x = (Dfp) other;
+        if (other instanceof Dfp x) {
             if (isNaN() || x.isNaN() || field.getRadixDigits() != x.field.getRadixDigits()) {
                 return false;
             }

diff --git a/...t/java/org/apache/commons/math4/legacy/core/jdkmath/AccurateMathStrictComparisonTest.java b/...t/java/org/apache/commons/math4/legacy/core/jdkmath/AccurateMathStrictComparisonTest.java
@@ -107,8 +107,7 @@ private static void reportFailedResults(Method mathMethod, Object[] params, Obje
         String format = null;
         long actL = 0;
         long expL = 0;
-        if (expected instanceof Double) {
-            Double exp = (Double) expected;
+        if (expected instanceof Double exp) {
             Double act = (Double) actual;
             if (isNumber(exp) && isNumber(act) && exp != 0) { // show difference as hex
                 actL = Double.doubleToLongBits(act);
@@ -121,8 +120,7 @@ private static void reportFailedResults(Method mathMethod, Object[] params, Obje
                 }
                 format = "%016x";
             }
-        } else if (expected instanceof Float) {
-            Float exp = (Float) expected;
+        } else if (expected instanceof Float exp) {
             Float act = (Float) actual;
             if (isNumber(exp) && isNumber(act) && exp != 0) { // show difference as hex
                 actL = Float.floatToIntBits(act);
@@ -143,13 +141,13 @@ private static void reportFailedResults(Method mathMethod, Object[] params, Obje
         }
         sb.append(") expected ");
         if (format != null) {
-            sb.append(String.format(format, expL));
+            sb.append(format.formatted(expL));
         } else {
             sb.append(expected);
         }
         sb.append(" actual ");
         if (format != null) {
-            sb.append(String.format(format, actL));
+            sb.append(format.formatted(actL));
         } else {
             sb.append(actual);
         }

diff --git a/...acy-core/src/test/java/org/apache/commons/math4/legacy/core/jdkmath/AccurateMathTest.java b/...acy-core/src/test/java/org/apache/commons/math4/legacy/core/jdkmath/AccurateMathTest.java
@@ -675,11 +675,11 @@ private static void assertAtan2(double y, double x, double numerator, double den
         if (numerator == 0) {
             // Exact including the sign.
             Assertions.assertEquals(numerator, v,
-                () -> String.format("atan2(%s, %s) should be %s but was %s", y, x, numerator, v));
+                () -> "atan2(%s, %s) should be %s but was %s".formatted(y, x, numerator, v));
         } else {
             final double expected = AccurateMath.PI * numerator / denominator;
             Assertions.assertEquals(expected, v, Precision.EPSILON,
-                () -> String.format("atan2(%s, %s) should be pi * %s / %s", y, x, numerator, denominator));
+                () -> "atan2(%s, %s) should be pi * %s / %s".formatted(y, x, numerator, denominator));
         }
     }
 

diff --git a/...ception/src/main/java/org/apache/commons/math4/legacy/exception/ConvergenceException.java b/...ception/src/main/java/org/apache/commons/math4/legacy/exception/ConvergenceException.java
@@ -16,6 +16,8 @@
  */
 package org.apache.commons.math4.legacy.exception;
 
+import java.io.Serial;
+
 import org.apache.commons.math4.legacy.exception.util.Localizable;
 import org.apache.commons.math4.legacy.exception.util.LocalizedFormats;
 
@@ -27,6 +29,7 @@
  */
 public class ConvergenceException extends MathIllegalStateException {
     /** Serializable version Id. */
+    @Serial
     private static final long serialVersionUID = 4330003017885151975L;
 
     /**

diff --git a/...n/src/main/java/org/apache/commons/math4/legacy/exception/DimensionMismatchException.java b/...n/src/main/java/org/apache/commons/math4/legacy/exception/DimensionMismatchException.java
@@ -16,6 +16,8 @@
  */
 package org.apache.commons.math4.legacy.exception;
 
+import java.io.Serial;
+
 import org.apache.commons.math4.legacy.exception.util.Localizable;
 import org.apache.commons.math4.legacy.exception.util.LocalizedFormats;
 
@@ -26,6 +28,7 @@
  */
 public class DimensionMismatchException extends MathIllegalNumberException {
     /** Serializable version Id. */
+    @Serial
     private static final long serialVersionUID = -8415396756375798143L;
     /** Correct dimension. */
     private final int dimension;

diff --git a/...on/src/main/java/org/apache/commons/math4/legacy/exception/InsufficientDataException.java b/...on/src/main/java/org/apache/commons/math4/legacy/exception/InsufficientDataException.java
@@ -16,6 +16,8 @@
  */
 package org.apache.commons.math4.legacy.exception;
 
+import java.io.Serial;
+
 import org.apache.commons.math4.legacy.exception.util.Localizable;
 import org.apache.commons.math4.legacy.exception.util.LocalizedFormats;
 
@@ -28,6 +30,7 @@ public class InsufficientDataException
     extends MathIllegalArgumentException {
 
     /** Serializable version Id. */
+    @Serial
     private static final long serialVersionUID = -2629324471511903359L;
 
     /**

diff --git a/...tion/src/main/java/org/apache/commons/math4/legacy/exception/MathArithmeticException.java b/...tion/src/main/java/org/apache/commons/math4/legacy/exception/MathArithmeticException.java
@@ -16,6 +16,8 @@
  */
 package org.apache.commons.math4.legacy.exception;
 
+import java.io.Serial;
+
 import org.apache.commons.math4.legacy.exception.util.Localizable;
 import org.apache.commons.math4.legacy.exception.util.LocalizedFormats;
 
@@ -29,6 +31,7 @@
  */
 public class MathArithmeticException extends MathRuntimeException {
     /** Serializable version Id. */
+    @Serial
     private static final long serialVersionUID = -6024911025449780478L;
 
     /**

diff --git a/...src/main/java/org/apache/commons/math4/legacy/exception/MathIllegalArgumentException.java b/...src/main/java/org/apache/commons/math4/legacy/exception/MathIllegalArgumentException.java
@@ -16,6 +16,8 @@
  */
 package org.apache.commons.math4.legacy.exception;
 
+import java.io.Serial;
+
 import org.apache.commons.math4.legacy.exception.util.Localizable;
 
 /**
@@ -28,6 +30,7 @@
  */
 public class MathIllegalArgumentException extends MathRuntimeException {
     /** Serializable version Id. */
+    @Serial
     private static final long serialVersionUID = -6024911025449780478L;
 
     /**

diff --git a/...n/src/main/java/org/apache/commons/math4/legacy/exception/MathIllegalNumberException.java b/...n/src/main/java/org/apache/commons/math4/legacy/exception/MathIllegalNumberException.java
@@ -16,6 +16,8 @@
  */
 package org.apache.commons.math4.legacy.exception;
 
+import java.io.Serial;
+
 import org.apache.commons.math4.legacy.exception.util.Localizable;
 
 /**
@@ -32,6 +34,7 @@ public class MathIllegalNumberException extends MathIllegalArgumentException {
     protected static final Integer INTEGER_ZERO = Integer.valueOf(0);
 
     /** Serializable version Id. */
+    @Serial
     private static final long serialVersionUID = -7447085893598031110L;
 
     /** Requested. */

diff --git a/...on/src/main/java/org/apache/commons/math4/legacy/exception/MathIllegalStateException.java b/...on/src/main/java/org/apache/commons/math4/legacy/exception/MathIllegalStateException.java
@@ -16,6 +16,8 @@
  */
 package org.apache.commons.math4.legacy.exception;
 
+import java.io.Serial;
+
 import org.apache.commons.math4.legacy.exception.util.Localizable;
 import org.apache.commons.math4.legacy.exception.util.LocalizedFormats;
 
@@ -28,6 +30,7 @@
  */
 public class MathIllegalStateException extends MathRuntimeException {
     /** Serializable version Id. */
+    @Serial
     private static final long serialVersionUID = -6024911025449780478L;
 
     /**

diff --git a/...-exception/src/main/java/org/apache/commons/math4/legacy/exception/MathInternalError.java b/...-exception/src/main/java/org/apache/commons/math4/legacy/exception/MathInternalError.java
@@ -16,6 +16,8 @@
  */
 package org.apache.commons.math4.legacy.exception;
 
+import java.io.Serial;
+
 import org.apache.commons.math4.legacy.exception.util.Localizable;
 import org.apache.commons.math4.legacy.exception.util.LocalizedFormats;
 
@@ -26,6 +28,7 @@
  */
 public class MathInternalError extends MathIllegalStateException {
     /** Serializable version Id. */
+    @Serial
     private static final long serialVersionUID = -6276776513966934846L;
     /** URL for reporting problems. */
     private static final String REPORT_URL = "https://issues.apache.org/jira/browse/MATH";

diff --git a/...exception/src/main/java/org/apache/commons/math4/legacy/exception/MathParseException.java b/...exception/src/main/java/org/apache/commons/math4/legacy/exception/MathParseException.java
@@ -16,6 +16,8 @@
  */
 package org.apache.commons.math4.legacy.exception;
 
+import java.io.Serial;
+
 import org.apache.commons.math4.legacy.exception.util.LocalizedFormats;
 
 /**
@@ -25,6 +27,7 @@
  */
 public class MathParseException extends MathIllegalStateException {
     /** Serializable version Id. */
+    @Serial
     private static final long serialVersionUID = -6024911025449780478L;
 
     /**

diff --git a/...ception/src/main/java/org/apache/commons/math4/legacy/exception/MathRuntimeException.java b/...ception/src/main/java/org/apache/commons/math4/legacy/exception/MathRuntimeException.java
@@ -16,6 +16,8 @@
  */
 package org.apache.commons.math4.legacy.exception;
 
+import java.io.Serial;
+
 import org.apache.commons.math4.legacy.exception.util.ExceptionContext;
 import org.apache.commons.math4.legacy.exception.util.ExceptionContextProvider;
 import org.apache.commons.math4.legacy.exception.util.Localizable;
@@ -32,6 +34,7 @@
 public class MathRuntimeException extends RuntimeException
     implements ExceptionContextProvider {
     /** Serializable version Id. */
+    @Serial
     private static final long serialVersionUID = 20120926L;
     /** Context. */
     private final ExceptionContext context;

diff --git a/...ain/java/org/apache/commons/math4/legacy/exception/MathUnsupportedOperationException.java b/...ain/java/org/apache/commons/math4/legacy/exception/MathUnsupportedOperationException.java
@@ -16,6 +16,8 @@
  */
 package org.apache.commons.math4.legacy.exception;
 
+import java.io.Serial;
+
 import org.apache.commons.math4.legacy.exception.util.Localizable;
 import org.apache.commons.math4.legacy.exception.util.LocalizedFormats;
 
@@ -29,6 +31,7 @@
  */
 public class MathUnsupportedOperationException extends MathRuntimeException {
     /** Serializable version Id. */
+    @Serial
     private static final long serialVersionUID = -6024911025449780478L;
 
     /**

diff --git a/...on/src/main/java/org/apache/commons/math4/legacy/exception/MaxCountExceededException.java b/...on/src/main/java/org/apache/commons/math4/legacy/exception/MaxCountExceededException.java
@@ -16,6 +16,8 @@
  */
 package org.apache.commons.math4.legacy.exception;
 
+import java.io.Serial;
+
 import org.apache.commons.math4.legacy.exception.util.Localizable;
 import org.apache.commons.math4.legacy.exception.util.LocalizedFormats;
 
@@ -26,6 +28,7 @@
  */
 public class MaxCountExceededException extends MathIllegalStateException {
     /** Serializable version Id. */
+    @Serial
     private static final long serialVersionUID = 4330003017885151975L;
     /**
      * Maximum number of evaluations.

diff --git a/.../main/java/org/apache/commons/math4/legacy/exception/MultiDimensionMismatchException.java b/.../main/java/org/apache/commons/math4/legacy/exception/MultiDimensionMismatchException.java
@@ -16,6 +16,8 @@
  */
 package org.apache.commons.math4.legacy.exception;
 
+import java.io.Serial;
+
 import org.apache.commons.math4.legacy.exception.util.Localizable;
 import org.apache.commons.math4.legacy.exception.util.LocalizedFormats;
 
@@ -26,6 +28,7 @@
  */
 public class MultiDimensionMismatchException extends MathIllegalArgumentException {
     /** Serializable version Id. */
+    @Serial
     private static final long serialVersionUID = -8415396756375798143L;
 
     /** Wrong dimensions. */

diff --git a/...eption/src/main/java/org/apache/commons/math4/legacy/exception/NoBracketingException.java b/...eption/src/main/java/org/apache/commons/math4/legacy/exception/NoBracketingException.java
@@ -16,6 +16,8 @@
  */
 package org.apache.commons.math4.legacy.exception;
 
+import java.io.Serial;
+
 import org.apache.commons.math4.legacy.exception.util.Localizable;
 import org.apache.commons.math4.legacy.exception.util.LocalizedFormats;
 
@@ -27,6 +29,7 @@
  */
 public class NoBracketingException extends MathIllegalArgumentException {
     /** Serializable version Id. */
+    @Serial
     private static final long serialVersionUID = -3629324471511904459L;
     /** Lower end of the interval. */
     private final double lo;

diff --git a/...cy-exception/src/main/java/org/apache/commons/math4/legacy/exception/NoDataException.java b/...cy-exception/src/main/java/org/apache/commons/math4/legacy/exception/NoDataException.java
@@ -16,6 +16,8 @@
  */
 package org.apache.commons.math4.legacy.exception;
 
+import java.io.Serial;
+
 import org.apache.commons.math4.legacy.exception.util.Localizable;
 import org.apache.commons.math4.legacy.exception.util.LocalizedFormats;
 
@@ -27,6 +29,7 @@
 public class NoDataException extends MathIllegalArgumentException {
 
     /** Serializable version Id. */
+    @Serial
     private static final long serialVersionUID = -3629324471511904459L;
 
     /**

diff --git a/...rc/main/java/org/apache/commons/math4/legacy/exception/NonMonotonicSequenceException.java b/...rc/main/java/org/apache/commons/math4/legacy/exception/NonMonotonicSequenceException.java
@@ -16,6 +16,8 @@
  */
 package org.apache.commons.math4.legacy.exception;
 
+import java.io.Serial;
+
 import org.apache.commons.math4.legacy.exception.util.LocalizedFormats;
 
 /**
@@ -26,6 +28,7 @@
  */
 public class NonMonotonicSequenceException extends MathIllegalNumberException {
     /** Serializable version Id. */
+    @Serial
     private static final long serialVersionUID = 20210531L;
     /**
      * Whether the sequence should be increasing.

diff --git a/...xception/src/main/java/org/apache/commons/math4/legacy/exception/NotANumberException.java b/...xception/src/main/java/org/apache/commons/math4/legacy/exception/NotANumberException.java
@@ -16,6 +16,8 @@
  */
 package org.apache.commons.math4.legacy.exception;
 
+import java.io.Serial;
+
 import org.apache.commons.math4.legacy.exception.util.LocalizedFormats;
 
 /**
@@ -25,6 +27,7 @@
  */
 public class NotANumberException extends MathIllegalNumberException {
     /** Serializable version Id. */
+    @Serial
     private static final long serialVersionUID = 20120906L;
 
     /**

diff --git a/...ion/src/main/java/org/apache/commons/math4/legacy/exception/NotFiniteNumberException.java b/...ion/src/main/java/org/apache/commons/math4/legacy/exception/NotFiniteNumberException.java
@@ -16,6 +16,8 @@
  */
 package org.apache.commons.math4.legacy.exception;
 
+import java.io.Serial;
+
 import org.apache.commons.math4.legacy.exception.util.Localizable;
 import org.apache.commons.math4.legacy.exception.util.LocalizedFormats;
 
@@ -26,6 +28,7 @@
  */
 public class NotFiniteNumberException extends MathIllegalNumberException {
     /** Serializable version Id. */
+    @Serial
     private static final long serialVersionUID = -6100997100383932834L;
 
     /**

diff --git a/...ception/src/main/java/org/apache/commons/math4/legacy/exception/NotPositiveException.java b/...ception/src/main/java/org/apache/commons/math4/legacy/exception/NotPositiveException.java
@@ -16,6 +16,8 @@
  */
 package org.apache.commons.math4.legacy.exception;
 
+import java.io.Serial;
+
 import org.apache.commons.math4.legacy.exception.util.Localizable;
 
 /**
@@ -25,6 +27,7 @@
  */
 public class NotPositiveException extends NumberIsTooSmallException {
     /** Serializable version Id. */
+    @Serial
     private static final long serialVersionUID = -2250556892093726375L;
 
     /**