[#529] FIX jdbc connection deadlock (#533)

Valery Kharseko

01.51.2025 512d2351717cb9301643fa34c4631efc5e4616c4

[#529] FIX jdbc connection deadlock (#533)

 opendj-server-legacy/src/main/java/org/opends/server/backends/jdbc/CachedConnection.java

@@ -11,7 +11,7 @@
 * Header, with the fields enclosed by brackets [] replaced by your own identifying
 * information: "Portions Copyright [year] [name of copyright owner]".
 *
 * Copyright 2024 3A Systems, LLC.
 * Copyright 2024-2025 3A Systems, LLC.
 */
package org.opends.server.backends.jdbc;

@@ -27,25 +27,25 @@
public class CachedConnection implements Connection {
    final Connection parent;

    static LoadingCache<String, BlockingQueue<Connection>> cached= CacheBuilder.newBuilder()
    static LoadingCache<String, BlockingQueue<CachedConnection>> cached= CacheBuilder.newBuilder()
            .expireAfterAccess(Long.parseLong(System.getProperty("org.openidentityplatform.opendj.jdbc.ttl","15000")), TimeUnit.MILLISECONDS)
            .removalListener(new RemovalListener<String, BlockingQueue<Connection>>() {
            .removalListener(new RemovalListener<String, BlockingQueue<CachedConnection>>() {
                @Override
                public void onRemoval(RemovalNotification<String, BlockingQueue<Connection>> notification) {
                public void onRemoval(RemovalNotification<String, BlockingQueue<CachedConnection>> notification) {
                    assert notification.getValue() != null;
                    for (Connection con: notification.getValue()) {
                    for (CachedConnection con: notification.getValue()) {
                            try {
                                if (!con.isClosed()) {
                                    con.close();
                                    con.parent.close();
                                }
                            } catch (SQLException e) {
                            }
                        }
                }
            })
            .build(new CacheLoader<String, BlockingQueue<Connection>>() {
            .build(new CacheLoader<String, BlockingQueue<CachedConnection>>() {
                @Override
                public BlockingQueue<Connection> load(String connectionString) throws Exception {
                public BlockingQueue<CachedConnection> load(String connectionString) throws Exception {
                    return new LinkedBlockingQueue<>();
                }
            });
@@ -61,11 +61,11 @@
    }

    static Connection getConnection(String connectionString, final int waitTime) throws Exception {
        Connection con=cached.get(connectionString).poll(waitTime,TimeUnit.MILLISECONDS);
        CachedConnection con=cached.get(connectionString).poll(waitTime,TimeUnit.MILLISECONDS);
        while(con!=null) {
            if (!con.isValid(0)) {
                try {
                    con.close();
                    con.parent.close();
                } catch (SQLException e) {
                    con=null;
                }
@@ -75,10 +75,10 @@
            }
        }
        try {
            con = DriverManager.getConnection(connectionString);
            con.setAutoCommit(false);
            con.setTransactionIsolation(TRANSACTION_READ_COMMITTED);
            return new CachedConnection(connectionString, con);
            final Connection conNew= DriverManager.getConnection(connectionString);
            conNew.setAutoCommit(false);
            conNew.setTransactionIsolation(TRANSACTION_READ_COMMITTED);
            return new CachedConnection(connectionString, conNew);
        }catch (SQLException e) { //max_connection server error: try recursion for reuse connection
            return getConnection(connectionString,(waitTime==0)?1:waitTime*2);
        }