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How to use createInstance method of org.powermock.reflect.internal.WhiteboxImpl class

Best Powermock code snippet using org.powermock.reflect.internal.WhiteboxImpl.createInstance

Source:WhiteboxImpl.java

...962			constructor = classThatContainsTheConstructorToTest.getDeclaredConstructor(parameterTypes);963		} catch (Exception e) {964			throw new ConstructorNotFoundException("Could not lookup the constructor", e);965		}966		return createInstance(constructor, arguments);967	}968	/**969	 * Invoke a constructor. Useful for testing classes with a private970	 * constructor.971	 * 972	 * 973	 * @return The object created after the constructor has been invoked.974	 * @throws Exception975	 *             If an exception occur when invoking the constructor.976	 */977	public static <T> T invokeConstructor(Class<T> classThatContainsTheConstructorToTest, Object... arguments) throws Exception {978		if (classThatContainsTheConstructorToTest == null) {979			throw new IllegalArgumentException("The class should contain the constructor cannot be null.");980		}981		Class<?>[] argumentTypes = null;982		if (arguments == null) {983			argumentTypes = new Class<?>[0];984		} else {985			argumentTypes = new Class<?>[arguments.length];986			for (int i = 0; i < arguments.length; i++) {987				argumentTypes[i] = getType(arguments[i]);988			}989		}990		Constructor<T> constructor = null;991		Constructor<T> potentialContstructorWrapped = null;992		Constructor<T> potentialContstructorPrimitive = null;993		try {994			potentialContstructorWrapped = classThatContainsTheConstructorToTest.getDeclaredConstructor(argumentTypes);995		} catch (Exception e) {996			// Do nothing, we'll try with primitive type next.997		}998		try {999			potentialContstructorPrimitive = classThatContainsTheConstructorToTest.getDeclaredConstructor(PrimitiveWrapper1000					.toPrimitiveType(argumentTypes));1001		} catch (Exception e) {1002			// Do nothing1003		}1004		if (potentialContstructorPrimitive == null && potentialContstructorWrapped == null) {1005			// Check if we can find a matching var args constructor.1006			constructor = getPotentialVarArgsConstructor(classThatContainsTheConstructorToTest, arguments);1007			if (constructor == null) {1008				throw new ConstructorNotFoundException("Failed to find a constructor with parameter types: [" + getArgumentTypesAsString(arguments)1009						+ "]");1010			}1011		} else if (potentialContstructorPrimitive == null && potentialContstructorWrapped != null) {1012			constructor = potentialContstructorWrapped;1013		} else if (potentialContstructorPrimitive != null && potentialContstructorWrapped == null) {1014			constructor = potentialContstructorPrimitive;1015		} else if (arguments == null || arguments.length == 0 && potentialContstructorPrimitive != null) {1016			constructor = potentialContstructorPrimitive;1017		} else {1018			throw new TooManyConstructorsFoundException(1019					"Could not determine which constructor to execute. Please specify the parameter types by hand.");1020		}1021		return createInstance(constructor, arguments);1022	}1023	@SuppressWarnings("unchecked")1024	private static <T> Constructor<T> getPotentialVarArgsConstructor(Class<T> classThatContainsTheConstructorToTest, Object... arguments) {1025		if (areAllArgumentsOfSameType(arguments)) {1026			Constructor<T>[] declaredConstructors = (Constructor<T>[]) classThatContainsTheConstructorToTest.getDeclaredConstructors();1027			for (Constructor<T> possibleVarArgsConstructor : declaredConstructors) {1028				if (possibleVarArgsConstructor.isVarArgs()) {1029					if (arguments == null || arguments.length == 0) {1030						return possibleVarArgsConstructor;1031					} else {1032						Class<?>[] parameterTypes = possibleVarArgsConstructor.getParameterTypes();1033						if (parameterTypes[parameterTypes.length - 1].getComponentType().isAssignableFrom(getType(arguments[0]))) {1034							return possibleVarArgsConstructor;1035						}1036					}1037				}1038			}1039		}1040		return null;1041	}1042	private static <T> T createInstance(Constructor<T> constructor, Object... arguments) throws Exception {1043		if (constructor == null) {1044			throw new IllegalArgumentException("Constructor cannot be null");1045		}1046		constructor.setAccessible(true);1047		T createdObject = null;1048		try {1049			if (constructor.isVarArgs()) {1050				Class<?>[] parameterTypes = constructor.getParameterTypes();1051				final int varArgsIndex = parameterTypes.length - 1;1052				Class<?> varArgsType = parameterTypes[varArgsIndex].getComponentType();1053				Object varArgsArrayInstance = createAndPopulateVarArgsArray(varArgsType, varArgsIndex, arguments);1054				Object[] completeArgumentList = new Object[parameterTypes.length];1055				for (int i = 0; i < varArgsIndex; i++) {1056					completeArgumentList[i] = arguments[i];...

createInstance

Using AI Code Generation

1WhiteboxImpl whitebox = WhiteboxImpl.createInstance(WhiteboxImpl.class);2String[] result = whitebox.invokeMethod(whitebox, "split", "a,b,c", ",");3assertThat(result).containsExactly("a", "b", "c");4WhiteboxImpl whitebox = WhiteboxImpl.createInstance(WhiteboxImpl.class);5String[] result = whitebox.invokeMethod(whitebox, "split", "a,b,c", ",");6assertThat(result).containsExactly("a", "b", "c");7WhiteboxImpl whitebox = WhiteboxImpl.createInstance(WhiteboxImpl.class);8String[] result = whitebox.invokeMethod(whitebox, "split", "a,b,c", ",");9assertThat(result).containsExactly("a", "b", "c");10WhiteboxImpl whitebox = WhiteboxImpl.createInstance(WhiteboxImpl.class);11String[] result = whitebox.invokeMethod(whitebox, "split", "a,b,c", ",");12assertThat(result).containsExactly("a", "b", "c");13WhiteboxImpl whitebox = WhiteboxImpl.createInstance(WhiteboxImpl.class);14String[] result = whitebox.invokeMethod(whitebox, "split", "a,b,c", ",");15assertThat(result).containsExactly("a", "b", "c");16WhiteboxImpl whitebox = WhiteboxImpl.createInstance(WhiteboxImpl.class);17String[] result = whitebox.invokeMethod(whitebox, "split", "a,b,c", ",");18assertThat(result).containsExactly("a", "b", "c");19WhiteboxImpl whitebox = WhiteboxImpl.createInstance(WhiteboxImpl.class);20String[] result = whitebox.invokeMethod(whitebox, "split", "a,b,c", ",");21assertThat(result).containsExactly("a", "b", "c");

createInstance

Using AI Code Generation

1import org.powermock.reflect.internal.WhiteboxImpl;2import java.lang.reflect.InvocationTargetException;3public class CreateInstance {4    public static void main(String[] args) throws ClassNotFoundException, NoSuchMethodException, InvocationTargetException, InstantiationException, IllegalAccessException {5        Class<?> clazz = Class.forName("com.example.PrivateConstructor");6        Object instance = WhiteboxImpl.createInstance(clazz);7        System.out.println(instance);8    }9}10import org.powermock.reflect.internal.WhiteboxImpl;11import java.lang.reflect.InvocationTargetException;12public class CreateInstance {13    public static void main(String[] args) throws ClassNotFoundException, NoSuchMethodException, InvocationTargetException, InstantiationException, IllegalAccessException {14        Class<?> clazz = Class.forName("com.example.PrivateConstructor");15        Object instance = WhiteboxImpl.createInstance(clazz);16        System.out.println(instance);17    }18}

createInstance

Using AI Code Generation

1    public static Object createInstance(String className, Object... args) {2        try {3            Class<?> targetClass = Class.forName(className);4            Class<?>[] argClasses = new Class<?>[args.length];5            for (int i = 0; i < args.length; i++) {6                argClasses[i] = args[i].getClass();7            }8            Constructor<?> constructor = targetClass.getConstructor(argClasses);9            return constructor.newInstance(args);10        } catch (Exception e) {11            return null;12        }13    }14    public static Object createInstance(String className, Object... args) {15        try {16            Class<?> targetClass = Class.forName(className);17            Class<?>[] argClasses = new Class<?>[args.length];18            for (int i = 0; i < args.length; i++) {19                argClasses[i] = args[i].getClass();20            }21            Constructor<?> constructor = targetClass.getConstructor(argClasses);22            return constructor.newInstance(args);23        } catch (Exception e) {24            return null;25        }26    }27    public static Object createInstance(String className, Object... args) {28        try {29            Class<?> targetClass = Class.forName(className);30            Class<?>[] argClasses = new Class<?>[args.length];31            for (int i = 0; i < args.length; i++) {32                argClasses[i] = args[i].getClass();33            }34            Constructor<?> constructor = targetClass.getConstructor(argClasses);35            return constructor.newInstance(args);36        } catch (Exception e) {37            return null;38        }39    }

createInstance

Using AI Code Generation

1public class WhiteboxImplTest {2    public void testCreateInstance() throws Exception {3        final String string = WhiteboxImpl.createInstance(String.class);4        assertEquals(0, string.length());5    }6}

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