/**

  Licensed to the Apache Software Foundation (ASF) under one or more

  contributor license agreements.  See the NOTICE file distributed with

  this work for additional information regarding copyright ownership.

  The ASF licenses this file to You 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.apache.commons.inject.api;

 import java.lang.annotation.Annotation;

 import java.lang.reflect.Array;

 public class Key<T> implements IKey<T> {

         public static final String NO_NAME = "";

         public static final Annotation[] NO_ANNOTATIONS = (Annotation[]) Array.newInstance(Annotation.class, 0);

         private final Class<T> type;

         private final String name;

         private final Annotation[] annotations;

         public Key(Class<T> pType, String pName, Annotation[] pAnnotations) {

                 if (pType == null) {

                         throw new NullPointerException("The keys type must not be null.");

                 }

                 this.type = pType;

                 if (pName == null) {

                         name = NO_NAME;

                 } else {

                         name = pName;

                 }

                 if (pAnnotations == null) {

                         annotations = NO_ANNOTATIONS;

                 } else {

                         annotations = pAnnotations;

                 }

         }

         public Key(Class<T> pType, String pName) {

                 this(pType, pName, NO_ANNOTATIONS);

         }

         public Key(Class<T> pType) {

                 this(pType, NO_NAME, NO_ANNOTATIONS);

         }

         @Override

         public Class<T> getType() {

                 return type;

         }

         @Override

         public String getName() {

                 return name;

         }

         @Override

         public Annotation[] getAnnotations() {

                 return annotations;

         }

         @Override

         public String toString() {

                 return toString(this);

         }

         public static String toString(IKey<?> pKey) {

                 final StringBuilder sb = new StringBuilder();

                 sb.append("Type=");

                 sb.append(pKey.getType().getName());

                 final String name = pKey.getName();

                 if (name.length() > 0) {

                         sb.append(", Name=");

                         sb.append(name);

                 }

                 final Annotation[] annotations = pKey.getAnnotations();

                 if (annotations.length > 0) {

                         sb.append(", Annotations=[");

                         for (int i = 0;  i < annotations.length;  i++) {

                                 if (i > 0) {

                                         sb.append(",");

                                 }

                                 sb.append(annotations[i]);

                         }

                         sb.append("]");

                 }

                 return sb.toString();

         }

 }