[BAEL-13506] - Split or move core-java-8 module (#7790)

core-java-modules/core-java-lang-math/src/main/resources/logback.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<configuration>
+    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+        <encoder>
+            <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n
+            </pattern>
+        </encoder>
+    </appender>
+
+    <root level="INFO">
+        <appender-ref ref="STDOUT" />
+    </root>
+</configuration>

core-java-modules/core-java-lang-math/src/test/java/com/baeldung/java8/UnsignedArithmeticUnitTest.java

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+package com.baeldung.java8;
+
+import org.junit.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.catchThrowable;
+import static org.junit.Assert.assertEquals;
+
+public class UnsignedArithmeticUnitTest {
+    @Test
+    public void whenDoublingALargeByteNumber_thenOverflow() {
+        byte b1 = 100;
+        byte b2 = (byte) (b1 << 1);
+
+        assertEquals(-56, b2);
+    }
+
+    @Test
+    public void whenComparingNumbers_thenNegativeIsInterpretedAsUnsigned() {
+        int positive = Integer.MAX_VALUE;
+        int negative = Integer.MIN_VALUE;
+
+        int signedComparison = Integer.compare(positive, negative);
+        assertEquals(1, signedComparison);
+
+        int unsignedComparison = Integer.compareUnsigned(positive, negative);
+        assertEquals(-1, unsignedComparison);
+
+        assertEquals(negative, positive + 1);
+    }
+
+    @Test
+    public void whenDividingNumbers_thenNegativeIsInterpretedAsUnsigned() {
+        int positive = Integer.MAX_VALUE;
+        int negative = Integer.MIN_VALUE;
+
+        assertEquals(-1, negative / positive);
+        assertEquals(1, Integer.divideUnsigned(negative, positive));
+
+        assertEquals(-1, negative % positive);
+        assertEquals(1, Integer.remainderUnsigned(negative, positive));
+    }
+
+    @Test
+    public void whenParsingNumbers_thenNegativeIsInterpretedAsUnsigned() {
+        Throwable thrown = catchThrowable(() -> Integer.parseInt("2147483648"));
+        assertThat(thrown).isInstanceOf(NumberFormatException.class);
+
+        assertEquals(Integer.MAX_VALUE + 1, Integer.parseUnsignedInt("2147483648"));
+    }
+
+    @Test
+    public void whenFormattingNumbers_thenNegativeIsInterpretedAsUnsigned() {
+        String signedString = Integer.toString(Integer.MIN_VALUE);
+        assertEquals("-2147483648", signedString);
+
+        String unsignedString = Integer.toUnsignedString(Integer.MIN_VALUE);
+        assertEquals("2147483648", unsignedString);
+    }
+}

core-java-modules/core-java-lang-math/src/test/java/com/baeldung/math/MathNewMethodsUnitTest.java

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+package com.baeldung.math;
+
+import static org.junit.Assert.assertEquals;
+
+import org.junit.Test;
+
+public class MathNewMethodsUnitTest {
+
+    @Test
+    public void whenAddExactToInteger_thenExpectCorrectArithmeticResult() {
+        assertEquals(150, Math.addExact(100, 50));                // Returns 150
+    }
+
+    @Test
+    public void whenSubstractExactFromInteger_thenExpectCorrectArithmeticResult() {
+        assertEquals(50, Math.subtractExact(100, 50));            // Returns 50
+    }
+
+    @Test
+    public void whenDecrementExactInteger_thenExpectCorrectArithmeticResult() {
+        assertEquals(99, Math.decrementExact(100));               // Returns 99
+    }
+
+    @Test
+    public void whenIncrementExactToInteger_thenExpectCorrectArithmeticResult() {
+        assertEquals(101, Math.incrementExact(100));              // Returns 101
+    }
+
+    @Test
+    public void whenMultiplyExactTwoIntegers_thenExpectCorrectArithmeticResult() {
+        assertEquals(500, Math.multiplyExact(100, 5));            // Returns 500
+    }
+
+    @Test
+    public void whenNegateExactInteger_thenExpectCorrectArithmeticResult() {
+        assertEquals(-100, Math.negateExact(100));                // Returns -100
+    }
+    
+    @Test(expected = ArithmeticException.class) 
+    public void whenAddToMaxInteger_thenThrowsArithmeticException() {
+        Math.addExact(Integer.MAX_VALUE, 1);                      // Throws ArithmeticException
+    }
+    
+    @Test(expected = ArithmeticException.class) 
+    public void whenDecrementMinInteger_thenThrowsArithmeticException() {
+        Math.decrementExact(Integer.MIN_VALUE);                   // Throws ArithmeticException
+    }
+    
+    @Test(expected = ArithmeticException.class) 
+    public void whenIncrementMaxLong_thenThrowsArithmeticException() {
+        Math.incrementExact(Long.MAX_VALUE);                      // Throws ArithmeticException
+    }
+    
+    @Test(expected = ArithmeticException.class) 
+    public void whenMultiplyMaxLong_thenThrowsArithmeticException() {
+        Math.multiplyExact(Long.MAX_VALUE, 2);                    // Throws ArithmeticException
+    }
+    
+    @Test(expected = ArithmeticException.class) 
+    public void whenNegateMinInteger_thenThrowsArithmeticException() {
+        Math.negateExact(Integer.MIN_VALUE);                      // MinInt value: −2.147.483.648, but MaxInt Value: 2.147.483.647  => Throws ArithmeticException
+    }
+    
+    @Test(expected = ArithmeticException.class) 
+    public void whenSubstractFromMinInteger_thenThrowsArithmeticException() {
+        Math.subtractExact(Integer.MIN_VALUE, 1);
+    }
+    
+    @Test
+    public void whenFloorDivTwoIntegers_thenExpectCorrectArithmeticResult() {
+        assertEquals(3, Math.floorDiv(7, 2));                     // Exact quotient is 3.5 so floor(3.5) == 3
+        assertEquals(-4, Math.floorDiv(-7, 2));                   // Exact quotient is -3.5 so floor(-3.5) == -4
+    }
+    
+    @Test
+    public void whenModDivTwoIntegers_thenExpectCorrectArithmeticResult() {
+        assertEquals(2, Math.floorMod(5, 3));                     // Returns 2: floorMod for positive numbers returns the same as % operator
+        assertEquals(1, Math.floorMod(-5, 3));                    // Returns 1 and not 2 because floorDiv(-5, 3) is -2 and not -1 and (-2*3) + (1) = -5
+    }
+    
+    @Test
+    public void whenNextDownOfDouble_thenExpectCorrectNumber() {
+        double number = 3.0;
+        double expected = 2.999999999999;
+        double delta = 0.00000001;
+        assertEquals(expected, Math.nextDown(number), delta);     // The delta defines the accepted error range
+    }
+    
+}

core-java-modules/core-java-lang-math/src/test/resources/.gitignore

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+*.class
+
+#folders#
+/target
+/neoDb*
+/data
+/src/main/webapp/WEB-INF/classes
+*/META-INF/*
+
+# Packaged files #
+*.jar
+*.war
+*.ear