Pithos_GSS » GSS

/*

 * Copyright 2007, 2008, 2009 Electronic Business Systems Ltd.

 *

 * This file is part of GSS.

 *

 * GSS is free software: you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation, either version 3 of the License, or

 * (at your option) any later version.

 *

 * GSS is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with GSS.  If not, see <http://www.gnu.org/licenses/>.

 */

package org.gss_project.gss.server.domain;

import java.io.Serializable;

import java.util.Date;

import javax.persistence.Column;

import javax.persistence.Embeddable;

import javax.persistence.Embedded;

import javax.persistence.EmbeddedId;

import javax.persistence.Entity;

import javax.persistence.JoinColumn;

import javax.persistence.ManyToOne;

import org.hibernate.annotations.Cache;

import org.hibernate.annotations.CacheConcurrencyStrategy;

/**

 * A file tag. This is basically a many-to-many relationship between User and

 * FileHeader, with an extra string which is the tag. For implementation

 * details, see Java Persistence With Hibernate, p. 303.

 *

 * @author droutsis

 */

@Entity

@Cache(usage=CacheConcurrencyStrategy.READ_WRITE)

public class FileTag  implements Serializable{

        /**

         * The composite ID of the object.

         */

        @Embeddable

        public static class FileTagId implements Serializable {

                /**

                 *

                 */

                private static final long serialVersionUID = 1L;

                /**

                 * The ID of the user.

                 */

                @Column(name = "userId")

                private Long userId;

                /**

                 * The ID of the file header.

                 */

                @Column(name = "fileId")

                private Long fileId;

                /**

                 * The actual tag.

                 */

                @Column(name = "tag")

                private String tag;

                @Override

                public boolean equals(final Object o) {

                        if (o != null && o instanceof FileTagId) {

                                final FileTagId that = (FileTagId) o;

                                return userId.equals(that.userId) && fileId.equals(that.fileId) && tag.equals(that.tag);

                        }

                        return false;

                }

                @Override

                public int hashCode() {

                        return userId.hashCode() + fileId.hashCode() + tag.hashCode();

                }

        }

        /**

         * Database id. Not to be set by user.

         */

        @EmbeddedId

        private FileTagId id;

        /*

         * No version field: immutable object.

         */

        /**

         * The audit information.

         */

        @SuppressWarnings("unused")

        @Embedded

        private AuditInfo auditInfo;

        /**

         * The user who added this tag.

         */

        @ManyToOne

        @JoinColumn(name = "userId", nullable = false, insertable=false, updatable=false)

        private User user;

        /**

         * The file to which this tag belongs.

         */

        @ManyToOne(optional = true)

        @JoinColumn(name = "fileId", nullable = false, insertable=false, updatable=false)

        private FileHeader file;

        /**

         * The name of the tag.

         */

        @Column(nullable=false, insertable=false, updatable=false)

        private String tag;

        /**

         * A default constructor.

         */

        public FileTag() {

                // Empty.

        }

        /**

         * The proper constructor to call, which guarantees referential integrity.

         *

         * @param aUser The user who adds the tag

         * @param aFile The file to which the tag is added

         * @param aTag The tag itself

         */

        public FileTag(final User aUser, final FileHeader aFile, final String aTag) {

                // Set fields

                user = aUser;

                file = aFile;

                tag = aTag;

                // Set identifier values

                id = new FileTagId();

                id.userId = aUser.getId();

                id.fileId = aFile.getId();

                id.tag = aTag;

                // Guarantee referential integrity

                aUser.getFileTags().add(this);

                aFile.getFileTags().add(this);

                final AuditInfo ai = new AuditInfo();

                ai.setCreatedBy(aUser);

                ai.setModifiedBy(aUser);

                final Date now = new Date();

                ai.setCreationDate(now);

                ai.setModificationDate(now);

                auditInfo = ai;

        }

        /**

         * Retrieve the FileTagId.

         *

         * @return the ID

         */

        public FileTagId getId() {

                return id;

        }

        /**

         * Retrieve the user.

         *

         * @return the user

         */

        public User getUser() {

                return user;

        }

        /**

         * Retrieve the file header.

         *

         * @return the fileheader

         */

        public FileHeader getFile() {

                return file;

        }

        /**

         * Retrieve the actual tag content.

         *

         * @return the tag

         */

        public String getTag() {

                return tag;

        }

        /**

         * Modify the audit info.

         *

         * @param newAuditInfo the new audit info

         */

        public void setAuditInfo(final AuditInfo newAuditInfo) {

                auditInfo = newAuditInfo;

        }

        /**

         * Modify the user.

         *

         * @param newUser the user to set

         */

        public void setUser(User newUser) {

                user = newUser;

        }

        /**

         * Modify the file.

         *

         * @param newFile the file to set

         */

        public void setFile(FileHeader newFile) {

                file = newFile;

        }

}