org.mariadb.jdbc.message.server.CachedPrepareResultPacket Maven / Gradle / Ivy
// SPDX-License-Identifier: LGPL-2.1-or-later
// Copyright (c) 2012-2014 Monty Program Ab
// Copyright (c) 2015-2021 MariaDB Corporation Ab
package org.mariadb.jdbc.message.server;
import java.io.IOException;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.atomic.AtomicBoolean;
import org.mariadb.jdbc.ServerPreparedStatement;
import org.mariadb.jdbc.client.Client;
import org.mariadb.jdbc.client.Context;
import org.mariadb.jdbc.client.ReadableByteBuf;
import org.mariadb.jdbc.client.socket.Reader;
/** Prepare packet result with flag indicating use */
public final class CachedPrepareResultPacket extends PrepareResultPacket {
private final AtomicBoolean closing = new AtomicBoolean();
private final AtomicBoolean cached = new AtomicBoolean();
private final List statements = new ArrayList<>();
/**
* Cache prepare result with flag indicating use
*
* @param buffer prepare packet buffer
* @param reader packet reader
* @param context connection context
* @throws IOException if any socket error occurs
*/
public CachedPrepareResultPacket(ReadableByteBuf buffer, Reader reader, Context context)
throws IOException {
super(buffer, reader, context);
}
/**
* Indicate that a prepare statement must be closed (if not in LRU cache)
*
* @param con current connection
* @throws SQLException if SQL
*/
public void close(Client con) throws SQLException {
if (!cached.get() && closing.compareAndSet(false, true)) {
con.closePrepare(this);
}
}
public void decrementUse(Client con, ServerPreparedStatement preparedStatement)
throws SQLException {
statements.remove(preparedStatement);
if (statements.size() == 0 && !cached.get()) {
close(con);
}
}
/**
* Increment use of prepare statement.
*
* @param preparedStatement new statement using prepare result
*/
public void incrementUse(ServerPreparedStatement preparedStatement) {
if (closing.get()) {
return;
}
if (preparedStatement != null) statements.add(preparedStatement);
}
/**
* Indicate that Prepare command is not on LRU cache anymore. closing prepare command if not used
*
* @param con current connection
*/
public void unCache(Client con) {
cached.set(false);
if (statements.size() <= 0) {
try {
close(con);
} catch (SQLException e) {
// eat
}
}
}
/**
* indicate that result is in LRU cache
*
* @return true if cached
*/
public boolean cache() {
if (closing.get()) {
return false;
}
return cached.compareAndSet(false, true);
}
/**
* Return prepare statement id.
*
* @return statement id
*/
public int getStatementId() {
return statementId;
}
/** Resetting cache in case of failover */
public void reset() {
statementId = -1;
for (ServerPreparedStatement stmt : statements) {
stmt.reset();
}
}
}