001    /*
002     * Copyright 2010-2013 JetBrains s.r.o.
003     *
004     * Licensed under the Apache License, Version 2.0 (the "License");
005     * you may not use this file except in compliance with the License.
006     * You may obtain a copy of the License at
007     *
008     * http://www.apache.org/licenses/LICENSE-2.0
009     *
010     * Unless required by applicable law or agreed to in writing, software
011     * distributed under the License is distributed on an "AS IS" BASIS,
012     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013     * See the License for the specific language governing permissions and
014     * limitations under the License.
015     */
016    
017    package org.jetbrains.jet.lang.resolve.java.kt;
018    
019    import com.intellij.psi.PsiAnnotation;
020    import com.intellij.psi.PsiClass;
021    import org.jetbrains.annotations.NotNull;
022    import org.jetbrains.annotations.Nullable;
023    import org.jetbrains.jet.lang.resolve.java.JvmStdlibNames;
024    import org.jetbrains.jet.lang.resolve.java.resolver.JavaAnnotationResolver;
025    
026    public class JetClassObjectAnnotation extends PsiAnnotationWithAbiVersion {
027    
028        private static final JetClassObjectAnnotation NULL_ANNOTATION = new JetClassObjectAnnotation(null);
029    
030        static {
031            NULL_ANNOTATION.checkInitialized();
032        }
033    
034        private JetClassObjectAnnotation(@Nullable PsiAnnotation psiAnnotation) {
035            super(psiAnnotation);
036        }
037    
038        @NotNull
039        public static JetClassObjectAnnotation get(@NotNull PsiClass psiClass) {
040            PsiAnnotation annotation =
041                    JavaAnnotationResolver.findOwnAnnotation(psiClass, JvmStdlibNames.JET_CLASS_OBJECT.getFqName().asString());
042            return annotation != null ? new JetClassObjectAnnotation(annotation) : NULL_ANNOTATION;
043        }
044    }