com.helger.db.jdbc.AbstractConnector.java Source code

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Here is the source code for com.helger.db.jdbc.AbstractConnector.java

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/**
 * Copyright (C) 2014-2018 Philip Helger (www.helger.com)
 * philip[at]helger[dot]com
 *
 * 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 com.helger.db.jdbc;

import java.io.Closeable;
import java.sql.SQLException;

import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import javax.annotation.concurrent.ThreadSafe;
import javax.sql.DataSource;

import org.apache.commons.dbcp2.BasicDataSource;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.helger.commons.annotation.Nonempty;
import com.helger.commons.annotation.OverrideOnDemand;
import com.helger.commons.concurrent.SimpleLock;
import com.helger.commons.string.ToStringGenerator;

/**
 * Abstract implementation of {@link IHasDataSource} based on
 * {@link BasicDataSource} implementation.
 *
 * @author Philip Helger
 */
@ThreadSafe
public abstract class AbstractConnector implements IHasDataSource, Closeable {
    private static final Logger LOGGER = LoggerFactory.getLogger(AbstractConnector.class);

    @Nonnull
    private final SimpleLock m_aLock = new SimpleLock();
    protected BasicDataSource m_aDataSource;

    public AbstractConnector() {
    }

    @Nonnull
    protected final SimpleLock getLock() {
        return m_aLock;
    }

    @Nonnull
    @Nonempty
    protected abstract String getJDBCDriverClassName();

    /**
     * @return Connection user name
     */
    @Nullable
    protected abstract String getUserName();

    /**
     * @return Connection password
     */
    @Nullable
    protected abstract String getPassword();

    /**
     * @return Name of the database to connect to
     */
    @Nonnull
    protected abstract String getDatabaseName();

    /**
     * @return The final connection URL to be used for connecting. May not be
     *         <code>null</code>.
     */
    @Nonnull
    public abstract String getConnectionUrl();

    @OverrideOnDemand
    protected boolean isUseDefaultAutoCommit() {
        return false;
    }

    @OverrideOnDemand
    protected boolean isPoolPreparedStatements() {
        return true;
    }

    @Nonnull
    public final DataSource getDataSource() {
        return m_aLock.locked(() -> {
            if (m_aDataSource == null) {
                // build data source
                m_aDataSource = new BasicDataSource();
                m_aDataSource.setDriverClassName(getJDBCDriverClassName());
                if (getUserName() != null)
                    m_aDataSource.setUsername(getUserName());
                if (getPassword() != null)
                    m_aDataSource.setPassword(getPassword());
                m_aDataSource.setUrl(getConnectionUrl());

                // settings
                m_aDataSource.setDefaultAutoCommit(Boolean.valueOf(isUseDefaultAutoCommit()));
                m_aDataSource.setPoolPreparedStatements(isPoolPreparedStatements());
            }
            return m_aDataSource;
        });
    }

    public final void close() {
        try {
            m_aLock.lockedThrowing(() -> {
                if (m_aDataSource != null) {
                    m_aDataSource.close();
                    m_aDataSource = null;

                    if (LOGGER.isDebugEnabled())
                        LOGGER.debug("Closed database connection to '" + getDatabaseName() + "'");
                }
            });
        } catch (final SQLException ex) {
            throw new IllegalStateException("Failed to close DataSource " + m_aDataSource, ex);
        }
    }

    @Override
    public String toString() {
        return new ToStringGenerator(this).append("DataSource", m_aDataSource).getToString();
    }
}