databaseconnection.java

来自「java 完全探索的随书源码」· Java 代码 · 共 18 行

public class DatabaseConnection {

  private static DatabaseConnection singleton;

  private DatabaseConnection() {
    // do steps to establish connection to database
    // ...
  }

  // only access to an instance of DatabaseConnection
  public static DatabaseConnection getInstance() {
    if ( singleton == null ) {
      singleton = new DatabaseConnection();
    }
    return singleton;
  }
}