Merge pull request #9584 from alimate/BAEL-4295

BAEL-4295: When Does Java Throw the ExceptionInInitializerError?

core-java-modules/core-java-exceptions-2/src/test/java/com/baeldung/exceptionininitializererror/ExceptionInInitializerErrorUnitTest.java

@@ -0,0 +1,55 @@
+package com.baeldung.exceptionininitializererror;
+
+import org.junit.Test;
+
+import java.lang.reflect.Constructor;
+
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+public class ExceptionInInitializerErrorUnitTest {
+
+    @Test
+    public void givenStaticVar_whenThrows_thenWrapsItInAnExceptionInInitializerError() {
+        assertThatThrownBy(StaticVar::new)
+          .isInstanceOf(ExceptionInInitializerError.class)
+          .hasCauseInstanceOf(RuntimeException.class);
+    }
+
+    @Test
+    public void givenStaticBlock_whenThrows_thenWrapsItInAnExceptionInInitializerError() {
+        assertThatThrownBy(StaticBlock::new)
+          .isInstanceOf(ExceptionInInitializerError.class)
+          .hasCauseInstanceOf(ArithmeticException.class);
+    }
+
+    private static class CheckedConvention {
+
+        private static Constructor<?> constructor;
+
+        static {
+            try {
+                constructor = CheckedConvention.class.getDeclaredConstructor();
+            } catch (NoSuchMethodException e) {
+                throw new ExceptionInInitializerError(e);
+            }
+        }
+    }
+
+    private static class StaticVar {
+
+        private static int state = initializeState();
+
+        private static int initializeState() {
+            throw new RuntimeException();
+        }
+    }
+
+    private static class StaticBlock {
+
+        private static int state;
+
+        static {
+            state = 42 / 0;
+        }
+    }
+}