package liquibase.integration.ant;
   
   import liquibase.Liquibase;
   import org.apache.tools.ant.AntClassLoader;
   import org.apache.tools.ant.BuildException;
   
   import java.io.Writer;
   
   public class ChangeLogSyncTask extends BaseLiquibaseTask {
  
      @Override
      public void execute() throws BuildException {
          super.execute();
  
          if (!shouldRun()) {
              return;
          }
  
          Liquibase liquibase = null;
          try {
              liquibase = createLiquibase();
  
              Writer writer = createOutputWriter();
              if (writer == null) {
                  liquibase.changeLogSync(getContexts());
              } else {
                  liquibase.changeLogSync(getContexts(), writer);
                  writer.flush();
                  writer.close();
              }
  
          } catch (Exception e) {
              throw new BuildException(e);
          } finally {
              closeDatabase(liquibase);
          }
      }
  }