Java Code Examples for java.lang.reflect.Constructor#getParameterCount()
The following examples show how to use
java.lang.reflect.Constructor#getParameterCount() .
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Example 1
| Source File: Package.java From openjdk-jdk9 with GNU General Public License v2.0 | 6 votes |
|
public static void checkAccess(AccessibleObject accessibleObject, Object obj)
throws IllegalAccessException,
InvocationTargetException,
InstantiationException
{
if (accessibleObject instanceof Field) {
Field field = (Field) accessibleObject;
field.set(obj, 42);
field.get(obj);
} else if (accessibleObject instanceof Method) {
Method method = (Method) accessibleObject;
method.invoke(obj);
} else if (accessibleObject instanceof Constructor) {
Constructor<?> constructor = (Constructor<?>) accessibleObject;
Object[] params = new Object[constructor.getParameterCount()];
constructor.newInstance(params);
}
}
Example 2
| Source File: ReflectionUtils.java From embedded-database-spring-test with Apache License 2.0 | 6 votes |
|
@SuppressWarnings("unchecked")
public static <T> T invokeConstructor(Class<?> targetClass, Object... args) {
Assert.notNull(targetClass, "Target class must not be null");
try {
for (Constructor<?> constructor : targetClass.getDeclaredConstructors()) {
if (constructor.getParameterCount() != args.length) {
continue;
}
Class<?>[] parameterTypes = constructor.getParameterTypes();
boolean parametersMatches = IntStream.range(0, args.length)
.allMatch(i -> ClassUtils.isAssignableValue(parameterTypes[i], args[i]));
if (parametersMatches) {
org.springframework.util.ReflectionUtils.makeAccessible(constructor);
return (T) constructor.newInstance(args);
}
}
throw new IllegalArgumentException(String.format("Could not find constructor on %s", targetClass));
} catch (Exception ex) {
org.springframework.util.ReflectionUtils.handleReflectionException(ex);
throw new IllegalStateException("Should never get here");
}
}
Example 3
| Source File: ActionEventTest.java From hawkbit with Eclipse Public License 1.0 | 6 votes |
|
@Override
protected RemoteEntityEvent<?> createRemoteEvent(final Action baseEntity,
final Class<? extends RemoteEntityEvent<?>> eventType) {
Constructor<?> constructor = null;
for (final Constructor<?> constructors : eventType.getDeclaredConstructors()) {
if (constructors.getParameterCount() == 4) {
constructor = constructors;
}
}
if (constructor == null) {
throw new IllegalArgumentException("No suitable constructor foundes");
}
try {
return (RemoteEntityEvent<?>) constructor.newInstance(baseEntity, 1L, 2L, "Node");
} catch (final ReflectiveOperationException e) {
fail("Exception should not happen " + e.getMessage());
}
return null;
}
Example 4
| Source File: PublicSuper.java From openjdk-jdk9 with GNU General Public License v2.0 | 6 votes |
|
public static void checkAccess(AccessibleObject accessibleObject, Object obj)
throws IllegalAccessException,
InvocationTargetException,
InstantiationException
{
if (accessibleObject instanceof Field) {
Field field = (Field) accessibleObject;
field.set(obj, 42);
field.get(obj);
} else if (accessibleObject instanceof Method) {
Method method = (Method) accessibleObject;
method.invoke(obj);
} else if (accessibleObject instanceof Constructor) {
Constructor<?> constructor = (Constructor<?>) accessibleObject;
Object[] params = new Object[constructor.getParameterCount()];
constructor.newInstance(params);
}
}
Example 5
| Source File: ObjectContainer.java From flink-statefun with Apache License 2.0 | 6 votes |
|
private static Constructor<?> findConstructorForInjection(Class<?> type) {
Constructor<?>[] constructors = type.getDeclaredConstructors();
Constructor<?> defaultCont = null;
for (Constructor<?> constructor : constructors) {
Annotation annotation = constructor.getAnnotation(Inject.class);
if (annotation != null) {
return constructor;
}
if (constructor.getParameterCount() == 0) {
defaultCont = constructor;
}
}
if (defaultCont != null) {
return defaultCont;
}
throw new RuntimeException("not injectable type " + type);
}
Example 6
| Source File: AbstractBeanDefinition.java From java-technology-stack with MIT License | 6 votes |
|
/**
* Return the resolved autowire code,
* (resolving AUTOWIRE_AUTODETECT to AUTOWIRE_CONSTRUCTOR or AUTOWIRE_BY_TYPE).
* @see #AUTOWIRE_AUTODETECT
* @see #AUTOWIRE_CONSTRUCTOR
* @see #AUTOWIRE_BY_TYPE
*/
public int getResolvedAutowireMode() {
if (this.autowireMode == AUTOWIRE_AUTODETECT) {
// Work out whether to apply setter autowiring or constructor autowiring.
// If it has a no-arg constructor it's deemed to be setter autowiring,
// otherwise we'll try constructor autowiring.
Constructor<?>[] constructors = getBeanClass().getConstructors();
for (Constructor<?> constructor : constructors) {
if (constructor.getParameterCount() == 0) {
return AUTOWIRE_BY_TYPE;
}
}
return AUTOWIRE_CONSTRUCTOR;
}
else {
return this.autowireMode;
}
}
Example 7
| Source File: ObjectContainer.java From stateful-functions with Apache License 2.0 | 6 votes |
|
private static Constructor<?> findConstructorForInjection(Class<?> type) {
Constructor<?>[] constructors = type.getDeclaredConstructors();
Constructor<?> defaultCont = null;
for (Constructor<?> constructor : constructors) {
Annotation annotation = constructor.getAnnotation(Inject.class);
if (annotation != null) {
return constructor;
}
if (constructor.getParameterCount() == 0) {
defaultCont = constructor;
}
}
if (defaultCont != null) {
return defaultCont;
}
throw new RuntimeException("not injectable type " + type);
}
Example 8
| Source File: App.java From java-slack-sdk with MIT License | 6 votes |
|
private String getEventTypeAndSubtype(Class<? extends Event> clazz) {
String cached = eventTypeAndSubtypeValues.get(clazz);
if (cached != null) {
return cached;
} else {
for (Constructor<?> constructor : clazz.getDeclaredConstructors()) {
if (constructor.getParameterCount() == 0) {
try {
Event event = (Event) constructor.newInstance();
String typeAndSubtype = event.getType();
if (event.getSubtype() != null) {
typeAndSubtype = event.getType() + ":" + event.getSubtype();
}
eventTypeAndSubtypeValues.put(clazz, typeAndSubtype);
return typeAndSubtype;
} catch (InstantiationException | IllegalAccessException | InvocationTargetException e) {
log.error("Unexpectedly failed to load event type for the class {}", clazz.getCanonicalName());
break;
}
}
}
}
return null;
}
Example 9
| Source File: SQLExceptionConverterFactory.java From lams with GNU General Public License v2.0 | 5 votes |
|
private static SQLExceptionConverter constructConverter(String converterClassName, ViolatedConstraintNameExtracter violatedConstraintNameExtracter) {
try {
LOG.tracev( "Attempting to construct instance of specified SQLExceptionConverter [{0}]", converterClassName );
final Class converterClass = ReflectHelper.classForName( converterClassName );
// First, try to find a matching constructor accepting a ViolatedConstraintNameExtracter param...
final Constructor[] ctors = converterClass.getDeclaredConstructors();
for ( Constructor ctor : ctors ) {
if ( ctor.getParameterTypes() != null && ctor.getParameterCount() == 1 ) {
if ( ViolatedConstraintNameExtracter.class.isAssignableFrom( ctor.getParameterTypes()[0] ) ) {
try {
return (SQLExceptionConverter) ctor.newInstance( violatedConstraintNameExtracter );
}
catch (Throwable ignore) {
// eat it and try next
}
}
}
}
// Otherwise, try to use the no-arg constructor
return (SQLExceptionConverter) converterClass.newInstance();
}
catch (Throwable t) {
LOG.unableToConstructSqlExceptionConverter( t );
}
return null;
}
Example 10
| Source File: Entity.java From Nukkit with GNU General Public License v3.0 | 5 votes |
|
public static Entity createEntity(String name, FullChunk chunk, CompoundTag nbt, Object... args) {
Entity entity = null;
if (knownEntities.containsKey(name)) {
Class<? extends Entity> clazz = knownEntities.get(name);
if (clazz == null) {
return null;
}
for (Constructor constructor : clazz.getConstructors()) {
if (entity != null) {
break;
}
if (constructor.getParameterCount() != (args == null ? 2 : args.length + 2)) {
continue;
}
try {
if (args == null || args.length == 0) {
entity = (Entity) constructor.newInstance(chunk, nbt);
} else {
Object[] objects = new Object[args.length + 2];
objects[0] = chunk;
objects[1] = nbt;
System.arraycopy(args, 0, objects, 2, args.length);
entity = (Entity) constructor.newInstance(objects);
}
} catch (Exception e) {
MainLogger.getLogger().logException(e);
}
}
}
return entity;
}
Example 11
| Source File: InternalContext.java From gadtry with Apache License 2.0 | 5 votes |
|
@SuppressWarnings("unchecked")
private static <T> Constructor<T> selectConstructor(Class<T> driver)
{
Constructor<T>[] constructors;
if (Creator.class.isAssignableFrom(driver)) {
constructors = (Constructor<T>[]) driver.getDeclaredConstructors();
}
else {
if (driver.isInterface() || Modifier.isAbstract(driver.getModifiers())) {
throw new IllegalStateException(driver + " cannot be instantiated, No binding entity class");
}
constructors = (Constructor<T>[]) driver.getConstructors(); //public
}
Constructor<T> noParameter = null;
for (Constructor<T> constructor : constructors) {
Autowired autowired = constructor.getAnnotation(Autowired.class);
if (autowired != null) {
return constructor;
}
if (constructor.getParameterCount() == 0) {
//find 'no parameter' Constructor, using class.newInstance()";
noParameter = constructor;
}
}
if (noParameter != null) {
return noParameter;
}
checkState(constructors.length == 1, String.format("%s has multiple public constructors, please ensure that there is only one", driver));
return constructors[0];
}
Example 12
| Source File: MethodCallMetadataValidator.java From yare with MIT License | 5 votes |
|
private static boolean hasDefaultPublicConstructor(Class<?> clazz) {
Constructor<?>[] constructors = clazz.getConstructors();
for (Constructor<?> constructor : constructors) {
if (constructor.getParameterCount() == 0) {
return true;
}
}
return false;
}
Example 13
| Source File: ConstructorTest.java From j2objc with Apache License 2.0 | 5 votes |
|
public void test_getParameterCount() throws Exception {
Class[] expectedParameters = new Class[0];
Constructor<?> constructor = ConstructorTestHelper.class.getConstructor(expectedParameters);
assertEquals(0, constructor.getParameterCount());
expectedParameters = new Class[] { Object.class };
constructor = ConstructorTestHelper.class.getConstructor(expectedParameters);
int count = constructor.getParameterCount();
assertEquals(1, count);
}
Example 14
| Source File: MethodsProcessor.java From Summer with MIT License | 5 votes |
|
private static Object newClass(Class clazz){
try {
for (Constructor<?> c : clazz.getDeclaredConstructors()) {
c.setAccessible(true);
if (c.getParameterCount() == 0) {
return c.newInstance();
}
}
}catch (Exception e){
LOGGER.error(e.getMessage());
}
return null;
}
Example 15
| Source File: MethodIdentifier.java From typesafeconfig-guice with Apache License 2.0 | 5 votes |
|
public boolean matchesConstructor(Class<?> clazz, Constructor<?> constructor, ScanResult scanResult) {
if (clazz.getCanonicalName().equals(className) && methodName.equals("<init>") && constructor.getParameterCount() == parameterTypeSignature.length)
{
boolean paramsMatch = true;
for (int i = 0; i < parameterTypeSignature.length; i++) {
paramsMatch = paramsMatch && parameterTypeSignature[i].instantiate(scanResult) == constructor.getParameters()[i].getType();
}
return paramsMatch;
}
return false;
}
Example 16
| Source File: BlockEntity.java From Jupiter with GNU General Public License v3.0 | 4 votes |
|
public static BlockEntity createBlockEntity(String type, FullChunk chunk, CompoundTag nbt, Object... args) {
type = type.replaceFirst("BlockEntity", ""); //TODO: Remove this after the first release
BlockEntity blockEntity = null;
if (knownBlockEntities.containsKey(type)) {
Class<? extends BlockEntity> clazz = knownBlockEntities.get(type);
if (clazz == null) {
return null;
}
for (Constructor constructor : clazz.getConstructors()) {
if (blockEntity != null) {
break;
}
if (constructor.getParameterCount() != (args == null ? 2 : args.length + 2)) {
continue;
}
try {
if (args == null || args.length == 0) {
blockEntity = (BlockEntity) constructor.newInstance(chunk, nbt);
} else {
Object[] objects = new Object[args.length + 2];
objects[0] = chunk;
objects[1] = nbt;
System.arraycopy(args, 0, objects, 2, args.length);
blockEntity = (BlockEntity) constructor.newInstance(objects);
}
} catch (Exception e) {
//ignore
}
}
}
return blockEntity;
}
Example 17
| Source File: BlockEntity.java From BukkitPE with GNU General Public License v3.0 | 4 votes |
|
public static BlockEntity createBlockEntity(String type, FullChunk chunk, CompoundTag nbt, Object... args) {
type = type.replaceFirst("BlockEntity", ""); //TODO: Remove this after the first release
BlockEntity blockEntity = null;
if (knownBlockEntities.containsKey(type)) {
Class<? extends BlockEntity> clazz = knownBlockEntities.get(type);
if (clazz == null) {
return null;
}
for (Constructor constructor : clazz.getConstructors()) {
if (blockEntity != null) {
break;
}
if (constructor.getParameterCount() != (args == null ? 2 : args.length + 2)) {
continue;
}
try {
if (args == null || args.length == 0) {
blockEntity = (BlockEntity) constructor.newInstance(chunk, nbt);
} else {
Object[] objects = new Object[args.length + 2];
objects[0] = chunk;
objects[1] = nbt;
System.arraycopy(args, 0, objects, 2, args.length);
blockEntity = (BlockEntity) constructor.newInstance(objects);
}
} catch (Exception e) {
//ignore
}
}
}
return blockEntity;
}
Example 18
| Source File: Entity.java From Jupiter with GNU General Public License v3.0 | 4 votes |
|
public static Entity createEntity(String name, FullChunk chunk, CompoundTag nbt, Object... args) {
Entity entity = null;
if (knownEntities.containsKey(name)) {
Class<? extends Entity> clazz = knownEntities.get(name);
if (clazz == null) {
return null;
}
for (Constructor constructor : clazz.getConstructors()) {
if (entity != null) {
break;
}
if (constructor.getParameterCount() != (args == null ? 2 : args.length + 2)) {
continue;
}
try {
if (args == null || args.length == 0) {
entity = (Entity) constructor.newInstance(chunk, nbt);
} else {
Object[] objects = new Object[args.length + 2];
objects[0] = chunk;
objects[1] = nbt;
System.arraycopy(args, 0, objects, 2, args.length);
entity = (Entity) constructor.newInstance(objects);
}
} catch (Exception e) {
MainLogger.getLogger().logException(e);
}
}
}
//server.getAI().addAIQueue(entity);
return entity;
}
Example 19
| Source File: BinderToConstructor.java From Diorite with MIT License | 4 votes |
|
@SuppressWarnings({"unchecked", "rawtypes"})
BinderToConstructor(Controller controller, Class<? extends T> type, Constructor<?> constructor)
{
this.controller = controller;
Constructor<? extends T> constructor1 = (Constructor<? extends T>) constructor;
constructor1.setAccessible(true);
MethodDescription.ForLoadedConstructor constructorDesc = new MethodDescription.ForLoadedConstructor(constructor);
Map<Class<? extends Annotation>, ? extends Annotation> scopeMap = controller.extractRawScopeAnnotations(constructorDesc);
Map<Class<? extends Annotation>, ? extends Annotation> qualifierMap = controller.extractRawQualifierAnnotations(constructorDesc);
int parameterCount = constructor.getParameterCount();
ArrayList<ControllerInjectValueData<?>> params = new ArrayList<>(parameterCount);
ParameterList<ParameterDescription.InDefinedShape> parameters = constructorDesc.getParameters();
for (int i = 0; i < parameterCount; i++)
{
ParameterDescription.InDefinedShape param = parameters.get(i);
ControllerInjectValueData<Object> value = controller.createValue(- 1, constructorDesc.getDeclaringType(), param.getType(), param,
param.getName(), scopeMap, qualifierMap);
params.add(value);
}
this.params = List.of(params.toArray(new ControllerInjectValueData[parameterCount]));
this.constructor = $this ->
{
Object[] args = new Object[parameterCount];
for (int i = 0; i < parameterCount; i++)
{
args[i] = this.params.get(i).tryToGet($this);
}
try
{
return constructor1.newInstance(args);
}
catch (InstantiationException | IllegalAccessException | InvocationTargetException e)
{
throw new RuntimeException("Can't bind value to " + constructor1.getDeclaringClass().getName() + " constructor. " +
Arrays.toString(constructor1.getParameterTypes()), e);
}
};
}
Example 20
| Source File: ObjectInitializer.java From java-slack-sdk with MIT License | 4 votes |
|
public static <T> T initProperties(T obj) {
Field currentField = null;
try {
for (Field field : obj.getClass().getDeclaredFields()) {
currentField = field;
if (Modifier.isStatic(field.getModifiers()) ||
Modifier.isFinal(field.getModifiers()) ||
Modifier.isAbstract(field.getModifiers())) {
continue;
}
field.setAccessible(true);
Class<?> type = field.getType();
if (field.getName().startsWith("initial")) {
// set as null
} else if (field.getName().startsWith("image")) {
// set as null
} else if (field.getName().equals("fallback")) {
// set as null
} else if (field.getName().equals("url")) {
field.set(obj, "https://www.example.com/test-url");
} else if (field.getName().equals("actionId") && type.equals(String.class)) {
field.set(obj, "action-" + System.currentTimeMillis() + "-" + RANDOM.nextInt(1024));
} else if (field.getName().equals("blockId") && type.equals(String.class)) {
field.set(obj, "block-" + System.currentTimeMillis() + "-" + RANDOM.nextInt(1024));
} else if (field.getName().equals("style") && type.equals(String.class)) {
field.set(obj, "primary");
} else if (field.getName().equals("initialDate") && type.equals(String.class)) {
field.set(obj, "2020-03-11");
} else if (type.equals(String.class)) {
field.set(obj, "str");
} else if (type.equals(Integer.class)) {
field.set(obj, 123);
} else if (type.equals(Long.class)) {
field.set(obj, 123L);
} else if (type.equals(Double.class)) {
field.set(obj, 12.3D);
} else if (type.equals(Boolean.class)) {
field.set(obj, false);
} else if (type.equals(List.class)) {
List listObj = (List) field.get(obj);
if (listObj != null) {
for (Object o : listObj) {
initProperties(o);
}
} else {
log.info("null List object detected {} in {}", field.getName(), obj.getClass().getSimpleName());
}
} else {
if (field.get(obj) != null) {
initProperties(field.get(obj));
continue;
}
for (Constructor<?> constructor : type.getDeclaredConstructors()) {
if (constructor.getParameterCount() == 0) {
Object childObj = constructor.newInstance();
initProperties(childObj);
field.set(obj, childObj);
continue;
}
}
log.info("Skipped a field which doesn't have non arg constructor: {} in {}", field.getName(), obj.getClass().getSimpleName());
}
}
return obj;
} catch (Exception e) {
// because this method can be used in initializer code
String message = "Failed to instantiate " + currentField.getType().getName() + " " + currentField.getName()
+ " in " + obj.getClass().getSimpleName();
throw new RuntimeException(message, e);
}
}
