nl.knaw.dans.common.lang.search.bean.SearchBeanUtil.java Source code

Introduction

Here is the source code for nl.knaw.dans.common.lang.search.bean.SearchBeanUtil.java

Source

/*******************************************************************************
 * Copyright 2015 DANS - Data Archiving and Networked Services
 *
 * 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 nl.knaw.dans.common.lang.search.bean;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;

import nl.knaw.dans.common.lang.ClassUtil;
import nl.knaw.dans.common.lang.search.Field;
import nl.knaw.dans.common.lang.search.Index;
import nl.knaw.dans.common.lang.search.bean.annotation.SearchBean;
import nl.knaw.dans.common.lang.search.bean.annotation.SearchField;
import nl.knaw.dans.common.lang.search.exceptions.CannotInstantiateIndexException;
import nl.knaw.dans.common.lang.search.exceptions.ObjectIsNotASearchBeanException;
import nl.knaw.dans.common.lang.search.exceptions.SearchBeanException;
import nl.knaw.dans.common.lang.search.simple.SimpleField;

import org.apache.commons.lang.StringUtils;

/**
 * Class with helper functions for working with search beans
 * 
 * @author lobo
 */
public class SearchBeanUtil {
    private static void checkSearchBean(Class<?> sbClass) throws ObjectIsNotASearchBeanException {
        if (!sbClass.isAnnotationPresent(SearchBean.class))
            throw new ObjectIsNotASearchBeanException(sbClass.toString());
    }

    public static String getTypeIdentifier(Class<?> sbClass) throws SearchBeanException {
        checkSearchBean(sbClass);
        return sbClass.getAnnotation(SearchBean.class).typeIdentifier();
    }

    public static List<String> getTypeHierarchy(Class<?> sbClass) throws SearchBeanException {
        checkSearchBean(sbClass);

        List<String> result = new ArrayList<String>();
        result.add(sbClass.getAnnotation(SearchBean.class).typeIdentifier());
        if (sbClass.getSuperclass().isAnnotationPresent(SearchBean.class)) {
            result.addAll(getTypeHierarchy(sbClass.getSuperclass()));
        }
        return result;
    }

    public static Field getPrimaryKey(Object searchBean) throws SearchBeanException {
        Class<?> sbClass = searchBean.getClass();
        checkSearchBean(sbClass);

        String primaryKeyName = getDefaultIndex(sbClass).getPrimaryKey();

        for (java.lang.reflect.Field classField : ClassUtil.getAllFields(sbClass).values()) {
            if (classField.isAnnotationPresent(SearchField.class)) {
                SearchField sbField = classField.getAnnotation(SearchField.class);
                if (sbField.name().equals(primaryKeyName)) {
                    Object fieldValue;
                    try {
                        fieldValue = getFieldValue(searchBean, classField.getName());
                    } catch (Exception e) {
                        throw new SearchBeanException("Error while trying to get the primary key of SearchBean "
                                + searchBean.getClass().toString(), e);
                    }

                    return new SimpleField(sbField.name(), fieldValue);
                }
            }
        }

        return null;
    }

    public static Index getDefaultIndex(Class<?> sbClass) throws SearchBeanException {
        checkSearchBean(sbClass);

        try {
            return sbClass.getAnnotation(SearchBean.class).defaultIndex().newInstance();
        } catch (InstantiationException e) {
            throw new CannotInstantiateIndexException(e);
        } catch (IllegalAccessException e) {
            throw new CannotInstantiateIndexException(e);
        }
    }

    public static String getFieldName(Object searchBean, String propertyName) throws NoSuchFieldException {
        Map<String, java.lang.reflect.Field> fields = ClassUtil.getAllFields(searchBean.getClass());
        java.lang.reflect.Field classField = fields.get(propertyName);
        if (classField == null)
            throw new NoSuchFieldException(propertyName);
        if (classField.isAnnotationPresent(SearchField.class))
            return classField.getAnnotation(SearchField.class).name();
        else
            return null;
    }

    public static Object getFieldValue(Object searchBean, String propertyName) throws SecurityException,
            NoSuchMethodException, IllegalArgumentException, IllegalAccessException, InvocationTargetException {
        String getMethodName = "get" + StringUtils.capitalize(propertyName);
        Method getMethod = searchBean.getClass().getMethod(getMethodName, new Class[] {});
        return getMethod.invoke(searchBean);
    }

}