/*
* RHQ Management Platform
* Copyright (C) 2005-2011 Red Hat, Inc.
* All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License, version 2, as
* published by the Free Software Foundation, and/or the GNU Lesser
* General Public License, version 2.1, also as published by the Free
* Software Foundation.
*
* This program 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 and the GNU Lesser General Public License
* for more details.
*
* You should have received a copy of the GNU General Public License
* and the GNU Lesser General Public License along with this program;
* if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
package org.rhq.core.domain.drift;
import static javax.persistence.CascadeType.MERGE;
import static javax.persistence.CascadeType.PERSIST;
import java.io.Serializable;
import java.util.LinkedHashSet;
import java.util.Set;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.EnumType;
import javax.persistence.Enumerated;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.NamedQueries;
import javax.persistence.NamedQuery;
import javax.persistence.OneToMany;
import javax.persistence.PrePersist;
import javax.persistence.SequenceGenerator;
import javax.persistence.Table;
import org.rhq.core.domain.drift.DriftConfigurationDefinition.DriftHandlingMode;
import org.rhq.core.domain.resource.Resource;
/**
* <p>
* The JPA Drift Server plugin (the RHQ default) implementation of DriftChangeSet. A change
* set instance has slightly different behavior based on whether or not it is version zero,
* that is the initial change set. This is due to the way in which pinned templates are
* supported.
* </p>
* <p>
* All change sets belong to a drift definition, and the definition is created from a
* {@link DriftDefinitionTemplate}. Templates can be pinned or unpinned. Each change set
* encapsulates a collection of changes that are represented by {@link JPADrift}.
* When a template is pinned there is a corresponding pinned snapshot that belongs to the
* template. Each definition created from that template uses that same pinned snapshot. In
* terms of implementation, the pinned snapshot is always change set version zero. As an
* optimization (of the default driftserver plugin data model design), the pinned snapshot
* is shared among definitions to avoid the overhead of making copies of what could
* potentially be very large numbers of Drift entities.
* </p>
* <p>
* When an instance of this class represents change set version zero, different fields will
* be "live" (i.e., non-null and in use) versus when it is not the initial change set.
* </p>
* <p>
* <strong>Note:</strong> Because persistence of this entity is managed by a drift server
* plugin, other entities managed by the RHQ core server cannot maintain direct references
* or JPA associations to this class. This restriction is necessary because entities managed
* by the RHQ core server interact with instance of this class through its drift entity
* interface which may have multiple implementation. Those implementations need not even
* be based on a RDBMS. Even though this entity is managed via a drift server plugin, it
* can maintain direct references and JPA associations to entities managed by the RHQ
* core server since they reside in the same database. That is however an implementation
* detail only of this class. It cannot be exposed in the drift interfaces.
* </p>
*
* @author Jay Shaughnessy
* @author John Sanda
*/
@Entity
@NamedQueries( { @NamedQuery(name = JPADriftChangeSet.QUERY_DELETE_BY_RESOURCES, query = "" //
+ "DELETE FROM JPADriftChangeSet dcs " //
+ " WHERE dcs.resource.id IN ( :resourceIds )"), //
@NamedQuery(name = JPADriftChangeSet.QUERY_DELETE_BY_DRIFTDEF_RESOURCE, query = "" //
+ "DELETE FROM JPADriftChangeSet dcs " //
+ " WHERE dcs.resource.id = :resourceId " //
+ " AND dcs.driftDefinition.id IN " //
+ " (SELECT dc.id " //
+ " FROM DriftDefinition dc " //
+ " WHERE dc.resource.id = :resourceId AND dc.name = :driftDefinitionName)" //
) })
@Table(name = "RHQ_DRIFT_CHANGE_SET")
@SequenceGenerator(allocationSize = org.rhq.core.domain.util.Constants.ALLOCATION_SIZE, name = "RHQ_DRIFT_CHANGE_SET_ID_SEQ", sequenceName = "RHQ_DRIFT_CHANGE_SET_ID_SEQ")
public class JPADriftChangeSet implements Serializable, DriftChangeSet<JPADrift> {
private static final long serialVersionUID = 1L;
public static final String QUERY_DELETE_BY_RESOURCES = "JPADriftChangeSet.deleteByResources";
public static final String QUERY_DELETE_BY_DRIFTDEF_RESOURCE = "JPADriftChangeSet.deleteByDriftDefResource";
@Column(name = "ID", nullable = false)
@GeneratedValue(strategy = GenerationType.AUTO, generator = "RHQ_DRIFT_CHANGE_SET_ID_SEQ")
@Id
private int id;
@Column(name = "CTIME", nullable = false)
private Long ctime = -1L;
// 0..N
@Column(name = "VERSION", nullable = false)
private int version;
@Column(name = "CATEGORY", nullable = false)
@Enumerated(EnumType.STRING)
private DriftChangeSetCategory category;
@JoinColumn(name = "DRIFT_DEFINITION_ID", referencedColumnName = "ID")
// TODO: remove this eager load, the drift tree build should be written to not need this
@ManyToOne(fetch = FetchType.EAGER)
private DriftDefinition driftDefinition;
// Note, this is mode at the time of the changeset processing. We cant use driftDefinition.mode because
// that is the "live" setting.
@Column(name = "DRIFT_HANDLING_MODE", nullable = false)
@Enumerated(EnumType.STRING)
private DriftHandlingMode driftHandlingMode;
@JoinColumn(name = "RESOURCE_ID", referencedColumnName = "ID")
@ManyToOne
private Resource resource;
/**
* The set of drift entries that make up this change set. If this instance of
* JPADriftChangeSet is change set version zero, then this field will be null because
* the drifts for the initial change set are accessed through a {@link JPADriftSet}.
*/
@OneToMany(mappedBy = "changeSet", cascade = { CascadeType.ALL })
private Set<JPADrift> drifts = new LinkedHashSet<JPADrift>();
/**
* This field is null unless this instance of JPADriftChangeSet is the initial change
* set. If the change set belongs to a definition that was created from a pinned
* template, then the {@link JPADriftSet} will be shared by all definitions created
* from the template.
*/
@ManyToOne(optional = true, cascade = { PERSIST, MERGE })
@JoinColumn(name = "DRIFT_SET_ID", referencedColumnName = "ID")
private JPADriftSet initialDriftSet;
protected JPADriftChangeSet() {
}
public JPADriftChangeSet(Resource resource, int version, DriftChangeSetCategory category,
DriftDefinition driftDefinition) {
this.resource = resource;
this.version = version;
this.category = category;
this.driftDefinition = driftDefinition;
if (driftDefinition != null) {
this.driftHandlingMode = driftDefinition.getDriftHandlingMode();
}
}
@Override
public String getId() {
return Integer.toString(id);
}
@Override
public void setId(String id) {
this.id = Integer.parseInt(id);
}
@Override
public Long getCtime() {
return ctime;
}
@PrePersist
void onPersist() {
this.ctime = System.currentTimeMillis();
}
@Override
public int getVersion() {
return version;
}
@Override
public void setVersion(int version) {
this.version = version;
}
@Override
public DriftChangeSetCategory getCategory() {
return category;
}
@Override
public void setCategory(DriftChangeSetCategory category) {
this.category = category;
}
@Override
public int getResourceId() {
if (resource == null) {
return 0;
}
return resource.getId();
}
@Override
public void setResourceId(int id) {
// This is a no-op because we maintain a JPA association with
// the owning resource and therefore use setResource(Resource r)
}
public Resource getResource() {
return resource;
}
public void setResource(Resource resource) {
this.resource = resource;
}
public DriftDefinition getDriftDefinition() {
return driftDefinition;
}
public void setDriftDefinition(DriftDefinition driftDefinition) {
this.driftDefinition = driftDefinition;
}
public DriftHandlingMode getDriftHandlingMode() {
return driftHandlingMode;
}
public void setDriftHandlingMode(DriftHandlingMode driftHandlingMode) {
this.driftHandlingMode = driftHandlingMode;
}
@Override
public int getDriftDefinitionId() {
if (driftDefinition == null) {
return 0;
}
return driftDefinition.getId();
}
@Override
public void setDriftDefinitionId(int id) {
driftDefinition.setId(id);
}
@Override
public Set<JPADrift> getDrifts() {
if (version > 0) {
return drifts;
}
// TODO do we need to check for null here?
// If this is the initial change set, initialDriftSet should be non-null so I am
// not sure whether or not a null check is necessary here.
//
// jsanda
return initialDriftSet.getDrifts();
}
@Override
public void setDrifts(Set<JPADrift> drifts) {
this.drifts = drifts;
}
public JPADriftSet getInitialDriftSet() {
return initialDriftSet;
}
public void setInitialDriftSet(JPADriftSet driftSet) {
initialDriftSet = driftSet;
}
@Override
public String toString() {
return "JPADriftChangeSet [id=" + id + ", resource=" + resource + ", version=" + version + "]";
}
}