001/* 002 * Syncany, www.syncany.org 003 * Copyright (C) 2011-2016 Philipp C. Heckel <philipp.heckel@gmail.com> 004 * 005 * This program is free software: you can redistribute it and/or modify 006 * it under the terms of the GNU General Public License as published by 007 * the Free Software Foundation, either version 3 of the License, or 008 * (at your option) any later version. 009 * 010 * This program is distributed in the hope that it will be useful, 011 * but WITHOUT ANY WARRANTY; without even the implied warranty of 012 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 013 * GNU General Public License for more details. 014 * 015 * You should have received a copy of the GNU General Public License 016 * along with this program. If not, see <http://www.gnu.org/licenses/>. 017 */ 018package org.syncany.operations.down; 019 020import java.util.ArrayList; 021import java.util.Collections; 022import java.util.List; 023 024import org.syncany.database.DatabaseVersion; 025import org.syncany.database.DatabaseVersionHeader; 026 027/** 028 * A branch represents a list of {@link DatabaseVersionHeader}s, thereby identifying a 029 * the history of a client's database. It can be compared to a sorted list of 030 * {@link DatabaseVersion} pointers. 031 * 032 * <p>Branches are used mainly in the {@link DatabaseReconciliator} to compare database 033 * versions and reconcile conflicts. 034 * 035 * @author Philipp C. Heckel (philipp.heckel@gmail.com) 036 */ 037public class DatabaseBranch { 038 private ArrayList<DatabaseVersionHeader> branch; 039 040 public DatabaseBranch() { 041 this.branch = new ArrayList<DatabaseVersionHeader>(); 042 } 043 044 public void add(DatabaseVersionHeader header) { 045 branch.add(header); 046 } 047 048 public void addAll(List<DatabaseVersionHeader> headers) { 049 branch.addAll(headers); 050 } 051 052 public int size() { 053 return branch.size(); 054 } 055 056 public DatabaseVersionHeader get(int index) { 057 if (index >= 0 && index < branch.size()) { 058 return branch.get(index); 059 } 060 return null; 061 } 062 063 public List<DatabaseVersionHeader> getAll() { 064 return Collections.unmodifiableList(branch); 065 } 066 067 public DatabaseVersionHeader getLast() { 068 if (branch.size() == 0) { 069 return null; 070 } 071 return branch.get(branch.size() - 1); 072 } 073 074 @Override 075 public String toString() { 076 return branch.toString(); 077 } 078 079 @Override 080 public DatabaseBranch clone() { 081 DatabaseBranch clonedBranch = new DatabaseBranch(); 082 clonedBranch.addAll(getAll()); 083 084 return clonedBranch; 085 } 086 087 @Override 088 public int hashCode() { 089 final int prime = 31; 090 int result = 1; 091 result = prime * result + ((branch == null) ? 0 : branch.hashCode()); 092 return result; 093 } 094 095 @Override 096 public boolean equals(Object obj) { 097 if (this == obj) { 098 return true; 099 } 100 if (obj == null) { 101 return false; 102 } 103 if (!(obj instanceof DatabaseBranch)) { 104 return false; 105 } 106 DatabaseBranch other = (DatabaseBranch) obj; 107 if (branch == null) { 108 if (other.branch != null) { 109 return false; 110 } 111 } 112 else if (!branch.equals(other.branch)) { 113 return false; 114 } 115 return true; 116 } 117}