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| package br.com.otavio.vraptor.custom; | |
| import static java.lang.Character.toUpperCase; | |
| import static java.util.Arrays.asList; | |
| import java.lang.reflect.AccessibleObject; | |
| import java.lang.reflect.Field; | |
| import java.lang.reflect.InvocationTargetException; | |
| import java.lang.reflect.Method; | |
| import java.util.ArrayList; | |
| import java.util.Arrays; | |
| import java.util.List; | |
| /** | |
| * Default implementation for {@link ReflectionProvider} that uses pure Java Reflection API. | |
| * | |
| * @author Otávio S Garcia | |
| */ | |
| public class JdkReflectionProvider implements ReflectionProvider { | |
| private static final List<String> GETTER_PREFIX_LIST = asList("is", "get"); | |
| @Override | |
| public List<Method> getMethodsFor(Class<?> clazz) { | |
| checkNotNull(clazz, "Input class can't be null"); | |
| List<Method> out = new ArrayList<Method>(); | |
| for (Class<?> current = clazz; current != null; current = current.getSuperclass()) { | |
| for (Method method : current.getDeclaredMethods()) { | |
| makeAcessible(method); | |
| out.add(method); | |
| } | |
| } | |
| return out; | |
| } | |
| @Override | |
| public Method getMethod(Class<?> clazz, String methodName, Class<?>... parameterTypes) { | |
| checkNotNull(clazz, "Input class can't be null"); | |
| checkNotNull(methodName, "Method name can't be null"); | |
| for (Class<?> current = clazz; current != null; current = current.getSuperclass()) { | |
| for (Method method : current.getDeclaredMethods()) { | |
| if (method.getName().equals(methodName) && typesAreEquals(method.getParameterTypes(), parameterTypes)) { | |
| makeAcessible(method); | |
| return method; | |
| } | |
| } | |
| } | |
| return null; | |
| } | |
| @Override | |
| public Object invoke(Object instance, Method method, Object... args) { | |
| checkNotNull(instance, "Input instance can't be null"); | |
| checkNotNull(method, "Input method can't be null"); | |
| try { | |
| makeAcessible(method); | |
| return method.invoke(instance, args); | |
| } catch (IllegalAccessException | InvocationTargetException e) { | |
| throw new IllegalStateException(e); | |
| } | |
| } | |
| @Override | |
| public Object invoke(Object instance, String methodName, Object... args) { | |
| checkNotNull(instance, "Input instance can't be null"); | |
| checkNotNull(methodName, "Input method name can't be null"); | |
| Class<?>[] parameterTypes = extractParameterTypes(args); | |
| Method method = getMethod(instance.getClass(), methodName, parameterTypes); | |
| checkNotNull(method, "Method %s isn't found on %s", method, instance.getClass()); | |
| makeAcessible(method); | |
| return invoke(instance, method, args); | |
| } | |
| @Override | |
| public Object invokeGetter(Object instance, String fieldName) { | |
| checkNotNull(instance, "Input instance can't be null"); | |
| checkNotNull(fieldName, "Field name can't be null"); | |
| String capitalizedName = captalize(fieldName); | |
| Method method = findGetter(instance, capitalizedName); | |
| checkNotNull(method, "A getter for %s isn't found on %s", fieldName, instance.getClass()); | |
| return invoke(instance, method); | |
| } | |
| private Method findGetter(Object instance, String capitalizedName) { | |
| for (String prefix : GETTER_PREFIX_LIST) { | |
| Method method = getMethod(instance.getClass(), prefix + capitalizedName); | |
| if (method != null) { | |
| return method; | |
| } | |
| } | |
| return null; | |
| } | |
| @Override | |
| public List<Field> getFieldsFor(Class<?> clazz) { | |
| checkNotNull(clazz, "Input class can't be null"); | |
| List<Field> out = new ArrayList<Field>(); | |
| for (Class<?> current = clazz; current != null; current = current.getSuperclass()) { | |
| for (Field field : current.getDeclaredFields()) { | |
| makeAcessible(field); | |
| out.add(field); | |
| } | |
| } | |
| return out; | |
| } | |
| @Override | |
| public Field getField(Class<?> clazz, String fieldName) { | |
| checkNotNull(clazz, "Input class can't be null"); | |
| checkNotNull(fieldName, "Field name can't be null"); | |
| for (Class<?> current = clazz; current != null; current = current.getSuperclass()) { | |
| for (Field field : current.getDeclaredFields()) { | |
| if (field.getName().equals(fieldName)) { | |
| makeAcessible(field); | |
| return field; | |
| } | |
| } | |
| } | |
| return null; | |
| } | |
| /** | |
| * Set field or method as acessible to speed up reflection access. | |
| */ | |
| private void makeAcessible(AccessibleObject object) { | |
| if (!object.isAccessible()) { | |
| object.setAccessible(true); | |
| } | |
| } | |
| private Class<?>[] extractParameterTypes(Object... args) { | |
| Class<?>[] parameterTypes = new Class<?>[args.length]; | |
| for (int j = 0; j < args.length; j++) { | |
| parameterTypes[j] = args[j].getClass(); | |
| } | |
| return parameterTypes; | |
| } | |
| private String captalize(String fieldName) { | |
| if (fieldName.length() == 1) { | |
| return fieldName.toUpperCase(); | |
| } | |
| return toUpperCase(fieldName.charAt(0)) + fieldName.substring(1); | |
| } | |
| private boolean typesAreEquals(Class<?>[] parameterTypes, Class<?>[] expectedTypes) { | |
| return parameterTypes.length == expectedTypes.length | |
| && Arrays.equals(parameterTypes, expectedTypes); | |
| } | |
| private void checkNotNull(Object object, String message, Object... messageParams) { | |
| if (object == null) { | |
| throw new NullPointerException(String.format(message, messageParams)); | |
| } | |
| } | |
| } |
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