我知道这可能是一些非常基本的东西，但我不确定我到底遗漏了什么。

我正试图加载一个属性文件并试图建立到MySQL的连接，但我遇到了java.sql.SQLException

database.jdbc.url = jdbc:mysql://localhost:3306/foo
database.jdbc.driver = "com.mysql.jdbc.Driver"
database.jdbc.username = "java"
database.jdbc.password = "whatever"

private static final String PROPERTIES_FILE = "MyDatabaseProperties.properties";

private static final Properties PROPERTIES = new Properties();

private static final String PROPERTY_URL = "database.jdbc.url";

//private static final String PROPERTY_DRIVER = "database.jdbc.driver";

private static final String PROPERTY_USERNAME = "database.jdbc.username";

private static final String PROPERTY_PASSWORD = "database.jdbc.password";

static {
 try {
  PROPERTIES.load(new FileInputStream(PROPERTIES_FILE));
 } catch (FileNotFoundException e) {
  e.printStackTrace();
 } catch (IOException e) {
  e.printStackTrace();
 }
}

/**
 * Returns a connection to the database.
 *
 * @return A connection to the database.
 * @throws SQLException If acquiring the connection fails.
 */
public Connection getConnection() throws SQLException {

 if (connection == null) {
  // 1.
  connection = DriverManager.getConnection(PROPERTIES.getProperty(PROPERTY_URL),
   PROPERTIES.getProperty(PROPERTY_USERNAME), PROPERTIES.getProperty(PROPERTY_PASSWORD)); // THROWS EXCEPTION

  // 2.
  connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/foo", "java", "whatever"); // CONNECTS FINE
 }
 System.out.println("Connected!");
 return connection;
}

当我硬编码URL，username和password时，连接建立时没有任何问题，但properties.getproperty引发异常。

java.sql.SQLException: Access denied for user '"java"'@'localhost' (using password: YES)
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:129)
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97)
    at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:122)
    at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:836)
    at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:456)
    at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:246)
    at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:197)
    at java.sql/java.sql.DriverManager.getConnection(DriverManager.java:677)
    at java.sql/java.sql.DriverManager.getConnection(DriverManager.java:228)
    at core.DatabaseLoader.getConnection(DatabaseLoader.java:74)
    at app.AppMain.main(AppMain.java:22)