JNDIルックアップを使用してデータベースへの接続を取得するWebアプリがあります。
接続は正常に機能し、クエリに問題はありません。接続が適切に閉じず、「スリープ」モードでスタックしているという問題が発生します（mysql管理者によると）。これは、それらが使用できなくなり、接続が不足することを意味します。
接続をプールに正常に戻すために私ができることについて、誰かが私にいくつかの指針を教えてもらえますか？
public class DatabaseBean {
private static final Logger logger = Logger.getLogger(DatabaseBean.class);
private Connection conn;
private PreparedStatement prepStmt;
/**
* Zero argument constructor
* Setup generic databse connection in here to avoid redundancy
* The connection details are in /META-INF/context.xml
*/
public DatabaseBean() {
try {
InitialContext initContext = new InitialContext();
DataSource ds = (DataSource) initContext.lookup("java:/comp/env/jdbc/mysite");
conn = ds.getConnection();
}
catch (SQLException SQLEx) {
logger.fatal("There was a problem with the database connection.");
logger.fatal(SQLEx);
logger.fatal(SQLEx.getCause());
}
catch (NamingException nameEx) {
logger.fatal("There was a naming exception");
logger.fatal(nameEx);
logger.fatal(nameEx.getCause());
}
}
/**
* Execute a query. Do not use for statements (update delete insert etc).
*
* @return A ResultSet of the execute query. A set of size zero if no results were returned. It is never null.
* @see #executeUpdate() for running update, insert delete etc.
*/
public ResultSet executeQuery() {
ResultSet result = null;
try {
result = prepStmt.executeQuery();
logger.debug(prepStmt.toString());
}
catch (SQLException SQLEx) {
logger.fatal("There was an error running a query");
logger.fatal(SQLEx);
}
return result;
}
をちょきちょきと切る
public void close() {
try {
prepStmt.close();
prepStmt = null;
conn.close();
conn = null;
} catch (SQLException SQLEx) {
logger.warn("There was an error closing the database connection.");
}
}
}
これは、データベース接続を使用するjavabean内にあります。
public LinkedList<ImportantNoticeBean> getImportantNotices() {
DatabaseBean noticesDBBean = new DatabaseBean();
LinkedList<ImportantNoticeBean> listOfNotices = new LinkedList<ImportantNoticeBean>();
try {
PreparedStatement preStmt = noticesDBBean.getConn().prepareStatement("SELECT pseudonym, message, date_to, date_from " +
"FROM importantnotices, users " +
"WHERE importantnotices.username = users.username " +
"AND NOW() >= date_from AND NOW() <= date_to;");
noticesDBBean.setPrepStmt(preStmt);
ResultSet result = noticesDBBean.executeQuery();
while (result.next()) {
ImportantNoticeBean noticeBean = new ImportantNoticeBean();
noticeBean.setAuthor(result.getString("pseudonym"));
noticeBean.setMessage(result.getString("message"));
noticeBean.setDateTo(result.getDate("date_to"));
noticeBean.setDateFrom(result.getDate("date_from"));
listOfNotices.add(noticeBean);
}
result.close();
} catch (SQLException SQLEx) {
logger.error("There was an error in ImportantNoticesBean.getImportantNotices()");
logger.error(SQLEx);
} finally {
noticesDBBean.close();
}
return listOfNotices;
}
<Context reloadable="true">
<Resource name="jdbc/mysite"
auth="Container"
type="javax.sql.DataSource"
username="user"
password="password"
driverClassName="com.mysql.jdbc.Driver"
url="jdbc:mysql://localhost:3306/mysite"
maxActive="10"
maxIdle="5"
maxWait="6000"
removeAbandoned="true"
logAbandoned="false"
removeAbandonedTimeout="20"
/>
</Context>