hikaricpjava-ee-8connection-leaks

connection leakage with hikari CP


I have jdbs template for sql for sql statements, and use hikari connection pool, after after several calls i took exception, i used try-with-resources, where is my mistake?(Servlet Container -Tomcat)

public class SimpleJdbcTemplate {

private Connection connection;
private DataSource dataSource;
private ResultSet resultSet;
PreparedStatement preparedStatement;
public SimpleJdbcTemplate(Connection connection) {
    this.connection = connection;
}
//private DataSourse datasource - из hikariconnectionpool

public SimpleJdbcTemplate(DataSource dataSource) {
    this.dataSource = dataSource;
}

public <T> List<T> query(String sql, RowMapper<T> rowMapper, Object... args) {
    try (PreparedStatement preparedStatement = dataSource.getConnection().prepareStatement(sql)){
        resultSet = null;
        List<T> result = new ArrayList<>();
                                                         

        int position = 1;
        for (Object arg : args) {
            preparedStatement.setObject(position, arg);
            position++;
        }
        if (sql.contains("UPDATE") || sql.contains("update") ||sql.toLowerCase().contains("delete")||sql.toLowerCase().contains("insert")) {
            preparedStatement.executeUpdate();
        } else{
            resultSet = preparedStatement.executeQuery();
            if (resultSet == null) {
                throw new SQLException("No resultsSet");
            }
            while (resultSet.next()) {
                result.add(rowMapper.mapRow(resultSet));
            }

        }
        log.info(result.toString());
        return result;
    } catch (SQLException e) {
        throw new IllegalStateException(e);

Logs:

24-Oct-2020 13:46:16.633 SEVERE [http-nio-8080-exec-3] org.apache.catalina.core.StandardWrapperValve.invoke Servlet.service() for servlet [servlets.view.MessendjerViewServlet] in context with path [/LabWork_war] threw exception java.lang.IllegalStateException: java.sql.SQLTransientConnectionException: HikariPool-1 - Connection is not available, request timed out after 30014ms. at repository.utill.SimpleJdbcTemplate.query(SimpleJdbcTemplate.java:52) at repository.jdbc.UserRepositoryImpl.findUserByUUID(UserRepositoryImpl.java:84) at service.UserService.findUser(UserService.java:71) at servlets.filter.AuthFilter.doFilter(AuthFilter.java:53) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:690) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343) at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:373) at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868) at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1589) at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1130) at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:630) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.base/java.lang.Thread.run(Thread.java:832) Caused by: java.sql.SQLTransientConnectionException: HikariPool-1 - Connection is not available, request timed out after 30014ms. at com.zaxxer.hikari.pool.HikariPool.createTimeoutException(HikariPool.java:695) at com.zaxxer.hikari.pool.HikariPool.getConnection(HikariPool.java:197) at com.zaxxer.hikari.pool.HikariPool.getConnection(HikariPool.java:162) at com.zaxxer.hikari.HikariDataSource.getConnection(HikariDataSource.java:100) at repository.utill.SimpleJdbcTemplate.query(SimpleJdbcTemplate.java:27) ... 22 more


Solution

  • Okey i founded mistake this line is dont work correctly(try-with-resources) (reparedStatement preparedStatement = dataSource.getConnection().prepareStatement(sql)) i think when i try to close connection it tooks a random connection from datasource(dataSource.getConnection()),so,my connection was always open, i reformated code to this

    public class SimpleJdbcTemplate {
    
    DataSource dataSource;
    
    
    //private DataSourse datasource - из hikariconnectionpool
    
    public SimpleJdbcTemplate(DataSource dataSource) {
        this.dataSource = dataSource;
    }
    
    public <T> List<T> query(String sql, RowMapper<T> rowMapper, Object... args) {  //TODO repair connection leak
        Connection connection = null;
        PreparedStatement preparedStatement = null;
        ResultSet resultSet = null;
        try {
            connection = dataSource.getConnection();
            preparedStatement = connection.prepareStatement(sql);
            resultSet = null;
            List<T> result = new ArrayList<>();
    
    
            int position = 1;
            for (Object arg : args) {
                preparedStatement.setObject(position, arg);
                position++;
            }
            if (sql.contains("UPDATE") || sql.contains("update") || sql.toLowerCase().contains("delete") || sql.toLowerCase().contains("insert")) {
                preparedStatement.executeUpdate();
            } else {
                resultSet = preparedStatement.executeQuery();
                if (resultSet == null) {
                    throw new SQLException("No resultsSet");
                }
                while (resultSet.next()) {
                    result.add(rowMapper.mapRow(resultSet));
                }
    
    
            }
            log.info(result.toString());
            return result;
        } catch (SQLException e) {
            throw new IllegalStateException(e);
        } finally {
            try {
                if (resultSet != null) {
                    resultSet.close();
                    log.info("resultes finaly closed? - {}", resultSet.isClosed());
                }
            } catch (SQLException throwables) {
                throwables.printStackTrace();
            }
            if (preparedStatement != null) {
                try {
    
                    preparedStatement.close();
                    preparedStatement.close();
    
                } catch (SQLException throwables) {
                    throwables.printStackTrace();
                }
            }
            try {
    
                if (connection != null) {
    
                    connection.close();
                    connection.close();
    
                }
            } catch (SQLException throwables) {
                throwables.printStackTrace();
            }
        }
    }
    }
    

    all worked as it should