package liquibase.sqlgenerator.core;

 import liquibase.database.Database;

 import liquibase.exception.ValidationErrors;

 import liquibase.sql.Sql;

 import liquibase.sqlgenerator.SqlGenerator;

 import liquibase.sqlgenerator.SqlGeneratorChain;

 import liquibase.sqlgenerator.SqlGeneratorFactory;

 import liquibase.statement.core.UnlockDatabaseChangeLogStatement;

 import liquibase.statement.core.UpdateStatement;

 public class UnlockDatabaseChangeLogGenerator extends AbstractSqlGenerator<UnlockDatabaseChangeLogStatement> {

     public ValidationErrors validate(UnlockDatabaseChangeLogStatement statement, Database database,

             SqlGeneratorChain sqlGeneratorChain) {

         return new ValidationErrors();

     }

     public Sql[] generateSql(UnlockDatabaseChangeLogStatement statement, Database database,

             SqlGeneratorChain sqlGeneratorChain) {

         String liquibaseSchema = database.getLiquibaseSchemaName();

         UpdateStatement releaseStatement = new UpdateStatement(liquibaseSchema,

                 database.getDatabaseChangeLogLockTableName());

         releaseStatement.addNewColumnValue("LOCKED", false);

         releaseStatement.addNewColumnValue("LOCKGRANTED", null);

         releaseStatement.addNewColumnValue("LOCKEDBY", null);

         releaseStatement.setWhereClause(database.escapeColumnName(liquibaseSchema,

                 database.getDatabaseChangeLogTableName(), "ID")

                 + " = 1");

         return SqlGeneratorFactory.getInstance().generateSql(releaseStatement, database);

     }

 }