de.micromata.genome.util.jdbc.TraceCreationBasicDataSource.java Source code

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Here is the source code for de.micromata.genome.util.jdbc.TraceCreationBasicDataSource.java

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//
// Copyright (C) 2010-2016 Micromata GmbH
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//  http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//

package de.micromata.genome.util.jdbc;

import java.sql.Connection;
import java.sql.SQLException;
import java.util.IdentityHashMap;
import java.util.Map;

import org.apache.commons.dbcp2.BasicDataSource;
import org.apache.log4j.Logger;

/**
 * Traces the allocation stack traces, of the jdbc connections.
 * 
 * This is usefull to figure out which code is responsible for not closing the conntection.
 * 
 * @author Roger Rene Kommer (r.kommer.extern@micromata.de)
 *
 */
public class TraceCreationBasicDataSource extends BasicDataSource {
    private static final Logger LOG = Logger.getLogger(TraceCreationBasicDataSource.class);
    private Map<Connection, StackTraceElement[]> allocatedStacks = new IdentityHashMap<>();

    @Override
    public Connection getConnection() throws SQLException {
        if (LOG.isDebugEnabled() == true) {
            LOG.debug("getConnection. max: " + getMaxTotal() + "; act: " + getNumActive());
        }
        Connection con = super.getConnection();
        allocatedStacks.put(con, new Throwable().getStackTrace());
        ConnectionWrapper wrapped = new ConnectionWrapper(con) {

            @Override
            public void close() throws SQLException {
                super.close();
                allocatedStacks.remove(getNestedConnection());
                if (LOG.isDebugEnabled() == true) {
                    LOG.debug("close. max: " + getMaxTotal() + "; act: " + getNumActive());
                }
            }

        };
        return wrapped;
    }

    /**
     * 
     * @return null if no open connections
     */
    public String getOpenConnectionsDump() {
        if (allocatedStacks.isEmpty() == true) {
            return null;
        }

        StringBuilder sb = new StringBuilder();
        sb.append("\n Open Connections: " + allocatedStacks.size()).append(":\n");
        for (Map.Entry<Connection, StackTraceElement[]> me : allocatedStacks.entrySet()) {
            sb.append("\n").append(me.getKey()).append("\n");
            for (StackTraceElement se : me.getValue()) {
                sb.append("  ").append(se.toString()).append("\n");
            }
        }
        return sb.toString();

    }
}