karaf-boot-tools/karaf-boot-maven-plugin/src/main/java/org/apache/karaf/boot/tools/maven/plugin/model/Bean.java

/**
 * 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.karaf.boot.tools.maven.plugin.model;

import java.lang.annotation.Annotation;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.List;
import java.util.SortedSet;
import java.util.TreeSet;

import javax.annotation.PostConstruct;
import javax.annotation.PreDestroy;
import javax.persistence.PersistenceContext;
import javax.persistence.PersistenceUnit;

public class Bean extends BeanRef {
    public String initMethod;
    public String destroyMethod;
    public SortedSet<Property> properties;
    public Field[] persistenceFields;
    public TransactionalDef transactionDef;

    public Bean(Class<?> clazz) {
        super(clazz);

        for (Method method : clazz.getDeclaredMethods()) {
            PostConstruct postConstruct = getEffectiveAnnotation(method, PostConstruct.class);
            if (postConstruct != null) {
                this.initMethod = method.getName();
            }
            PreDestroy preDestroy = getEffectiveAnnotation(method, PreDestroy.class);
            if (preDestroy != null) {
                this.destroyMethod = method.getName();
            }
        }
        this.persistenceFields = getPersistenceFields();
        this.transactionDef = new JavaxTransactionFactory().create(clazz);
        if (this.transactionDef == null) {
            this.transactionDef = new SpringTransactionFactory().create(clazz);
        }
        properties = new TreeSet<Property>();
    }

    private Field[] getPersistenceFields() {
        List<Field> persistenceFields = new ArrayList<Field>();
        Field[] fields = clazz.getDeclaredFields();
        for (Field field : fields) {
            PersistenceContext persistenceContext = field.getAnnotation(PersistenceContext.class);
            PersistenceUnit persistenceUnit = field.getAnnotation(PersistenceUnit.class);
            if (persistenceContext !=null || persistenceUnit != null) {
                 persistenceFields.add(field);
            }
        }
        return persistenceFields.toArray(new Field[]{});
    }
    
    public void resolve(Matcher matcher) {
        Class<?> curClass = this.clazz;
        while (curClass != null && curClass != Object.class) {
            resolveProperties(matcher, curClass);
            curClass = curClass.getSuperclass();
        }
    }
    
    private void resolveProperties(Matcher matcher, Class<?> curClass) {
        for (Field field : curClass.getDeclaredFields()) {
            Property prop = Property.create(matcher, field);
            if (prop != null) {
                properties.add(prop);
            }
        }
    }

    private static <T extends Annotation> T getEffectiveAnnotation(Method method, Class<T> annotationClass) {
        final Class<?> methodClass = method.getDeclaringClass();
        final String name = method.getName();
        final Class<?>[] params = method.getParameterTypes();

        // 1. Current class
        final T rootAnnotation = method.getAnnotation(annotationClass);
        if (rootAnnotation != null) {
            return rootAnnotation;
        }

        // 2. Superclass
        final Class<?> superclass = methodClass.getSuperclass();
        if (superclass != null) {
            final T annotation = getMethodAnnotation(superclass, name, params, annotationClass);
            if (annotation != null)
                return annotation;
        }

        // 3. Interfaces
        for (final Class<?> intfs : methodClass.getInterfaces()) {
            final T annotation = getMethodAnnotation(intfs, name, params, annotationClass);
            if (annotation != null)
                return annotation;
        }

        return null;
    }

    private static <T extends Annotation> T getMethodAnnotation(Class<?> searchClass, String name, Class<?>[] params,
            Class<T> annotationClass) {
        try {
            Method method = searchClass.getMethod(name, params);
            return getEffectiveAnnotation(method, annotationClass);
        } catch (NoSuchMethodException e) {
            return null;
        }
    }


    @Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        result = prime * result + ((clazz == null) ? 0 : clazz.getName().hashCode());
        result = prime * result + ((id == null) ? 0 : id.hashCode());
        return result;
    }

    @Override
    public String toString() {
        return clazz.getName();
    }

    public void writeProperties(PropertyWriter writer) {
        for (Property property : properties) {
            writer.writeProperty(property);
        }
    }
    
}