com.nec.strudel.entity.key.CompoundKeyFinder.java Source code

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Here is the source code for com.nec.strudel.entity.key.CompoundKeyFinder.java

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/*******************************************************************************
 * Copyright 2015 Junichi Tatemura
 *
 * 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 com.nec.strudel.entity.key;

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

import org.apache.commons.beanutils.BeanUtils;

public class CompoundKeyFinder extends KeyFinder {
    private final Map<String, Method> getters;
    private final Class<?> idClass;
    private final Class<?> valueClass;

    public CompoundKeyFinder(Class<?> idClass, Map<String, Method> getters) {
        this.idClass = idClass;
        this.getters = getters;
        this.valueClass = getters.values().iterator().next().getDeclaringClass();
    }

    @Override
    public Object getKey(Object entity) {
        if (!valueClass.isInstance(entity)) {
            throw new IllegalArgumentException(
                    "invalid class given (" + entity.getClass().getName() + ")" + " expected:" + valueClass);
        }
        try {
            Object id = idClass.newInstance();
            for (Map.Entry<String, Method> en : getters.entrySet()) {
                Object value = en.getValue().invoke(entity);
                BeanUtils.setProperty(id, en.getKey(), value);
            }
            return id;
        } catch (InstantiationException ex) {
            throw new RuntimeException(ex);
        } catch (IllegalAccessException ex) {
            throw new RuntimeException(ex);
        } catch (IllegalArgumentException ex) {
            throw new RuntimeException(ex);
        } catch (InvocationTargetException ex) {
            throw new RuntimeException(ex);
        }
    }

}