Add ConstructorUtilsExamples

Author: robertsmieja

src/test/java/com/robertsmieja/example/apache/commons/lang3/ConstructorUtilsExamples.java

@@ -0,0 +1,41 @@
+package com.robertsmieja.example.apache.commons.lang3;
+
+import org.apache.commons.lang3.reflect.ConstructorUtils;
+import org.junit.Test;
+
+import java.lang.reflect.Constructor;
+import java.lang.reflect.InvocationTargetException;
+
+import static org.junit.Assert.assertNotNull;
+
+public class ConstructorUtilsExamples {
+
+    public static class CoolClassWithConstructors {
+        public CoolClassWithConstructors(){}
+        public CoolClassWithConstructors(String stringArg){}
+        public CoolClassWithConstructors(int intArg) {}
+    }
+
+
+    @Test
+    public void constructorUtilsExample() throws IllegalAccessException, InvocationTargetException, InstantiationException, NoSuchMethodException {
+        Constructor<CoolClassWithConstructors> emptyCosntructor = ConstructorUtils.getAccessibleConstructor(CoolClassWithConstructors.class);
+        Constructor<CoolClassWithConstructors> stringConstructor = ConstructorUtils.getAccessibleConstructor(CoolClassWithConstructors.class, String.class);
+        Constructor<CoolClassWithConstructors> intConstructor = ConstructorUtils.getAccessibleConstructor(CoolClassWithConstructors.class, int.class);
+
+        assertNotNull(emptyCosntructor);
+        assertNotNull(stringConstructor);
+        assertNotNull(intConstructor);
+
+        CoolClassWithConstructors instance = emptyCosntructor.newInstance();
+        assertNotNull(instance);
+
+        CoolClassWithConstructors emptyConstructorInstance = ConstructorUtils.invokeConstructor(CoolClassWithConstructors.class);
+        CoolClassWithConstructors stringConstructorInstance = ConstructorUtils.invokeConstructor(CoolClassWithConstructors.class, "Argument");
+        CoolClassWithConstructors intConstructorInstance = ConstructorUtils.invokeConstructor(CoolClassWithConstructors.class, 1);
+
+        assertNotNull(emptyConstructorInstance);
+        assertNotNull(stringConstructorInstance);
+        assertNotNull(intConstructorInstance);
+    }
+}