org.ngrinder.model.BaseEntity.java Source code

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Here is the source code for org.ngrinder.model.BaseEntity.java

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/* 
 * 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 org.ngrinder.model;

import com.google.gson.annotations.Expose;
import org.apache.commons.lang.builder.ToStringBuilder;
import org.apache.commons.lang.builder.ToStringStyle;

import javax.persistence.*;
import java.io.Serializable;
import java.lang.reflect.Field;
import java.lang.reflect.Modifier;

import static org.ngrinder.common.util.ExceptionUtils.processException;

/**
 * Base Entity. This has a long type ID field
 *
 * @param <M> wrapped entity type
 * @author Liu Zhifei
 * @author JunHo Yoon
 * @since 3.0
 */
@MappedSuperclass
public class BaseEntity<M> implements Serializable {

    private static final long serialVersionUID = 8571113820348514692L;

    @Expose
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "id", unique = true, nullable = false, insertable = true, updatable = false)
    private Long id;

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    @Override
    public String toString() {
        return ToStringBuilder.reflectionToString(this, ToStringStyle.SHORT_PREFIX_STYLE);
    }

    /**
     * This function is used to check whether the entity id exist. It is not
     * used to check the entity existence in DB. It can be used to check the
     * entity in controller, which is passed from page.
     *
     * @return true if exists
     */
    public boolean exist() {
        return id != null && id != 0;
    }

    /**
     * Merge source entity into current entity.
     *
     * Only not null value is merged.
     *
     * @param source merge source
     * @return merged entity
     */
    @SuppressWarnings("unchecked")
    public M merge(M source) {
        Field forDisplay = null;
        try {
            Field[] fields = getClass().getDeclaredFields();
            // Iterate over all the attributes
            for (Field each : fields) {
                if (each.isSynthetic()) {
                    continue;
                }
                final int modifiers = each.getModifiers();
                if (Modifier.isFinal(modifiers) || Modifier.isStatic(modifiers)) {
                    continue;
                }
                forDisplay = each;
                if (!each.isAccessible()) {
                    each.setAccessible(true);
                }
                final Object value = each.get(source);
                if (value != null) {
                    each.set(this, value);
                }
            }
            return (M) this;
        } catch (Exception e) {
            String displayName = (forDisplay == null) ? "Empty" : forDisplay.getName();
            throw processException(
                    displayName + " - Exception occurred while merging an entity from " + source + " to " + this,
                    e);
        }
    }

    /**
     * Clone current entity.
     *
     * Only not null value is merged.
     *
     * @param toInstance instance to which the value is copied.
     * @return cloned entity
     */
    public M cloneTo(M toInstance) {
        Field forDisplay = null;
        try {
            Field[] fields = getClass().getDeclaredFields();
            // Iterate over all the attributes
            for (Field each : fields) {
                if (each.isSynthetic()) {
                    continue;
                }
                final int modifiers = each.getModifiers();
                if (Modifier.isFinal(modifiers) || Modifier.isStatic(modifiers)) {
                    continue;
                }
                forDisplay = each;
                final Cloneable annotation = each.getAnnotation(Cloneable.class);
                if (annotation == null) {
                    continue;
                }
                if (!each.isAccessible()) {
                    each.setAccessible(true);
                }
                each.set(toInstance, each.get(this));
            }
            return toInstance;
        } catch (Exception e) {
            String displayName = (forDisplay == null) ? "Empty" : forDisplay.getName();
            throw processException(displayName + " - Exception occurred while cloning an entity from " + this
                    + " to " + toInstance, e);
        }
    }
}