--- /dev/null
+/*
+ * Copyright 2008 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.wamblee.system.adapters;
+
+import java.lang.reflect.Constructor;
+import java.lang.reflect.Member;
+import java.lang.reflect.Modifier;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+import org.wamblee.collections.CollectionFilter;
+import org.wamblee.conditions.Condition;
+import org.wamblee.system.core.RequiredInterface;
+import org.wamblee.system.core.Scope;
+import org.wamblee.system.core.SystemAssemblyException;
+
+public class ConstructorConfiguration {
+ private Class _class;
+ private Constructor<?> _constructor;
+ private ParameterValues _values;
+ private boolean _publicOnly;
+
+ /**
+ * Constructs the configuration. By default no constructor is selected and
+ * one of {@link #select(Class...)} or
+ * {@link #greedy()} must be called.
+ * @param aClass Class to construct.
+ */
+ public ConstructorConfiguration(Class aClass) {
+ _class = aClass;
+ _constructor = null;
+ _publicOnly = true;
+ }
+
+ /**
+ * Sets whether or no non public constructors are also considered.
+ * Reset the choice of a constructor.
+ * @param aNonPublic
+ * @return
+ */
+ public ConstructorConfiguration setNonPublic(boolean aNonPublic) {
+ _publicOnly = !aNonPublic;
+ _constructor = null;
+ _values = null;
+ return this;
+ }
+
+ /**
+ * Selects an explicit constructor.
+ * @param aTypes Arguments of the constructor.
+ * @return Return the injector to allow call chaining.
+ */
+ public ConstructorConfiguration select(Class... aTypes) {
+ try {
+ _constructor = _class.getDeclaredConstructor(aTypes);
+ } catch (Exception e) {
+ throw new SystemAssemblyException(e.getMessage(), e);
+ }
+ resetValues();
+ return this;
+ }
+
+ /**
+ * Selects the greediest constructor.
+ * @return The injector to allow call chaining.
+ * @throws SystemAssemblyException if the greediest constructor cannot be uniquely
+ * identified.
+ */
+ public ConstructorConfiguration greedy() {
+ Constructor<?>[] declared = _class.getDeclaredConstructors();
+ if (declared.length == 0) {
+ throw new SystemAssemblyException("Class '" + _class
+ + " is an interface, primitive type, or array");
+ }
+ int max = -1;
+ List<Constructor<?>> checked = new ArrayList<Constructor<?>>();
+ CollectionFilter.filter(Arrays.asList(declared), checked,
+ new Condition<Constructor<?>>() {
+ @Override
+ public boolean matches(Constructor<?> aObject) {
+ if ( !_publicOnly ) {
+ return true;
+ } else {
+ return Modifier.isPublic(aObject.getModifiers());
+ }
+ }
+ });
+ for (Constructor ctor : checked) {
+ if (ctor.getParameterTypes().length > max) {
+ max = ctor.getParameterTypes().length;
+ }
+ }
+ final int max2 = max;
+ List<Constructor<?>> ctors = checked;
+ List<Constructor<?>> longest = new ArrayList<Constructor<?>>();
+ CollectionFilter.filter(ctors, longest,
+ new Condition<Constructor<?>>() {
+ @Override
+ public boolean matches(Constructor<?> aObject) {
+ return aObject.getParameterTypes().length == max2;
+ }
+ });
+ if (longest.size() > 1) {
+ throw new SystemAssemblyException(
+ "Greediest constructor cannot be uniquely determined");
+ }
+ _constructor = longest.get(0);
+ resetValues();
+ return this;
+ }
+
+ public ParameterValues getParameters() {
+ getConstructor(); // initialize constructor if needed.
+ return _values;
+ }
+
+ /**
+ * Resets the values.
+ */
+ private void resetValues() {
+ _constructor.setAccessible(true);
+ _values = new ParameterValues(_constructor.getParameterTypes());
+ }
+
+ /**
+ * Creates the object in the given scope.
+ * @param aScope Scope containing required interfaces for this object.
+ * @return object.
+ */
+ public Object create(Scope aScope) {
+ Object[] values = _values.values(aScope);
+ try {
+ return getConstructor().newInstance(values);
+ } catch (Exception e) {
+ throw new SystemAssemblyException("Could not construct object "
+ + getConstructor() + " " + Arrays.asList(values), e);
+ }
+ }
+
+ public List<RequiredInterface> getRequiredInterfaces() {
+ getConstructor(); // initialize constructor if needed.
+ return _values.getRequiredInterfaces();
+ }
+
+ private Constructor getConstructor() {
+ if (_constructor == null ) {
+ greedy();
+ }
+ return _constructor;
+ }
+}
git://wamblee.org / utils / blobdiff