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.PsiAnnotationMemberValue;
021    import com.intellij.psi.PsiLiteralExpression;
022    import org.jetbrains.annotations.NotNull;
023    import org.jetbrains.annotations.Nullable;
024    
025    public class PsiAnnotationUtils {
026    
027        private PsiAnnotationUtils() {
028        }
029    
030        @NotNull
031        public static String getStringAttribute(@Nullable PsiAnnotation annotation, @NotNull String field, @NotNull String defaultValue) {
032            return getAttribute(annotation, field, defaultValue);
033        }
034    
035        public static boolean getBooleanAttribute(@Nullable PsiAnnotation annotation, @NotNull String field, boolean defaultValue) {
036            return getAttribute(annotation, field, defaultValue);
037        }
038    
039        public static int getIntAttribute(@Nullable PsiAnnotation annotation, @NotNull String field, int defaultValue) {
040            return getAttribute(annotation, field, defaultValue);
041        }
042    
043        @NotNull
044        private static <T> T getAttribute(@Nullable PsiAnnotation annotation, @NotNull String field, @NotNull T defaultValue) {
045            if (annotation == null) {
046                return defaultValue;
047            }
048            else {
049                PsiAnnotationMemberValue value = annotation.findAttributeValue(field);
050                if (value instanceof PsiLiteralExpression) {
051                    PsiLiteralExpression attributeValue = (PsiLiteralExpression) value;
052                    return (T) attributeValue.getValue();
053                }
054                else {
055                    return defaultValue;
056                }
057            }
058        }
059    
060    }