[英]HikariCP Wrapper (thread safety)
我正在學習使用HikariCP(我是Java新手),我發現了一個包裝器,但我認為這不是線程安全性,那么單例的實例是線程安全性,而不是方法getConnection()。 該類是這樣的:
public class HikariCPWrapper{
private static final HikariCPWrapper INSTANCE;
private HikariDataSource ds;
static
{
INSTANCE = new HikariCPWrapper();
}
private HikariCPWrapper(){
HikariConfig config = new HikariConfig();
//config.set...
//...
ds = new HikariDataSource(config);
}
public static HikariCPWrapper getInstance ()
{
return INSTANCE;
}
public Connection getConnection() throws SQLException
{
return ds.getConnection();
}
}
好吧,我需要將參數發送到HikariConfig或HikariDataSource,所以我以這種方式重新編寫了它:
public interface IConnectionProvider {
void init(String jdbcUrl, String user, String password);
Connection getConnection() throws SQLException;
}
public class ConnectionProviderHikariCP implements IConnectionProvider{
private static final ConnectionProviderHikariCP INSTANCE;
private final HikariDataSource hikariDataSource;
private Boolean initialized;
//class initializer:
static
{
INSTANCE = new ConnectionProviderHikariCP();
}
private ConnectionProviderHikariCP() {
hikariDataSource = new HikariDataSource();
initialized = false;
}
public static ConnectionProviderHikariCP getInstance() {
return INSTANCE;
}
@Override
public synchronized void init(String jdbcUrl, String user, String password) {
hikariDataSource.setJdbcUrl(jdbcUrl);
hikariDataSource.setUsername(user);
hikariDataSource.setPassword(password);
initialized = true;
}
@Override
public synchronized Connection getConnection() throws SQLException {
if(!initialized)
throw new UnsupportedOperationException("Debe inicializar mediante el método Init() primero!!!!!.");
return hikariDataSource.getConnection();
}
}
我用這種方式:
IConnectionProvider connectionProvider = ConnectionProviderHikariCP.getInstance();
connectionProvider.init(url, user, passwd);
BaseDAOFactory fatory = new MySqlDAOFactory(connectionProvider);
IExerciseBO exerciseBO = new ExerciseBO(fatory);
但是我沒有Java經驗,所以我需要您的建議。 一流(原始)線程安全嗎? 我的實現線程安全嗎?
HikariCP本身是線程安全的。 據我了解,您正在嘗試做的是防止通過init()
方法初始化HikariDataSource
之前的調用者getConnection()
。 大概您還想防止多次調用init()
數據源。
就池吞吐量而言,用同步方法包裝getConnection()
通常是一個壞主意。 根據上面的代碼,我建議使用以下模式:
public class ConnectionProviderHikariCP implements IConnectionProvider {
private static final ConnectionProviderHikariCP INSTANCE;
private final HikariDataSource hikariDataSource;
private AtomicBoolean initialized;
//class initializer:
static
{
INSTANCE = new ConnectionProviderHikariCP();
}
private ConnectionProviderHikariCP() {
hikariDataSource = new HikariDataSource();
initialized = new AtomicInteger();
}
public static ConnectionProviderHikariCP getInstance() {
return INSTANCE;
}
@Override
public void init(String jdbcUrl, String user, String password) {
if (initialized.compareAndSet(false, true)) {
hikariDataSource.setJdbcUrl(jdbcUrl);
hikariDataSource.setUsername(user);
hikariDataSource.setPassword(password);
}
else {
throw new IllegalStateException("Connection provider already initialized.");
}
}
@Override
public Connection getConnection() throws SQLException {
if (initialized.get()) {
return hikariDataSource.getConnection();
}
throw new UnsupportedOperationException("Debe inicializar mediante el método Init() primero!!!!!.");
}
}
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.