001    /*
002     * Sonar, open source software quality management tool.
003     * Copyright (C) 2008-2011 SonarSource
004     * mailto:contact AT sonarsource DOT com
005     *
006     * Sonar is free software; you can redistribute it and/or
007     * modify it under the terms of the GNU Lesser General Public
008     * License as published by the Free Software Foundation; either
009     * version 3 of the License, or (at your option) any later version.
010     *
011     * Sonar is distributed in the hope that it will be useful,
012     * but WITHOUT ANY WARRANTY; without even the implied warranty of
013     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014     * Lesser General Public License for more details.
015     *
016     * You should have received a copy of the GNU Lesser General Public
017     * License along with Sonar; if not, write to the Free Software
018     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02
019     */
020    package org.sonar.jpa.entity;
021    
022    import java.sql.Connection;
023    import java.sql.ResultSet;
024    import java.sql.SQLException;
025    import java.sql.Statement;
026    
027    import javax.persistence.*;
028    
029    @Entity
030    @Table(name = SchemaMigration.TABLE_NAME, uniqueConstraints = { @UniqueConstraint(columnNames = { "version" }) })
031    public class SchemaMigration {
032    
033      public final static int VERSION_UNKNOWN = -1;
034      public static final int LAST_VERSION = 181;
035    
036      public final static String TABLE_NAME = "schema_migrations";
037    
038      @Id
039      @Column(name = "version", updatable = true)
040      private String version;
041    
042      public String getVersion() {
043        return version;
044      }
045    
046      public void setVersion(String s) {
047        this.version = s;
048      }
049    
050      public void setVersion(int i) {
051        this.version = String.valueOf(i);
052      }
053    
054      public static int getCurrentVersion(Connection connection) {
055        Statement stmt = null;
056        ResultSet rs = null;
057        int version = VERSION_UNKNOWN;
058        try {
059          stmt = connection.createStatement();
060          rs = stmt.executeQuery("SELECT version FROM " + SchemaMigration.TABLE_NAME);
061          while (rs.next()) {
062            int i = Integer.parseInt(rs.getString(1));
063            if (i > version) {
064              version = i;
065            }
066          }
067        } catch (SQLException e) {
068          // ignore
069        } finally {
070          close(rs);
071          close(stmt);
072        }
073    
074        return version;
075      }
076    
077      private static void close(ResultSet rs) {
078        if (rs != null) {
079          try {
080            rs.close();
081          } catch (SQLException e) {
082            // why does close() throw a checked-exception ???
083          }
084        }
085      }
086    
087      private static void close(Statement st) {
088        if (st != null) {
089          try {
090            st.close();
091          } catch (SQLException e) {
092            // why does close() throw a checked-exception ???
093          }
094        }
095      }
096    }