Apache Log4j Core Implementation provides the functional components of the logging system. Users are free to create their own plugins and include them in the logging configuration. Apache Log4j Core is a required module to use Apache Log4j.

Bytecode (Java 8) for Apache Log4j Core Implementation is provided in a separate JAR file like log4j-core-2.14.1.jar.

Source Code files for Apache Log4j API are provided in both binary packge like apache-log4j-2.14.1-bin.zip and source package like apache-log4j-2.14.1-src.zip. You can download them at Apache Log4j Website.

You can also browse Source Code files for Apache Log4j Core Implementation 2.14.1 below.

⏎ org/apache/logging/log4j/core/appender/db/jdbc/AbstractDriverManagerConnectionSource.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.logging.log4j.core.appender.db.jdbc;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.Properties;

import org.apache.logging.log4j.Logger;
import org.apache.logging.log4j.core.config.Property;
import org.apache.logging.log4j.core.config.plugins.PluginBuilderAttribute;
import org.apache.logging.log4j.core.config.plugins.PluginElement;
import org.apache.logging.log4j.core.config.plugins.validation.constraints.Required;
import org.apache.logging.log4j.status.StatusLogger;

/**
 * A {@link ConnectionSource} that uses a JDBC connection string, a user name, and a password to call
 * {@link DriverManager#getConnection(String, String, String)}.
 * <p>
 * This plugin does not provide any connection pooling unless it is available through the connection string and driver
 * itself. This handy to get you off the ground without having to deal with JNDI.
 * </p>
 */
public class AbstractDriverManagerConnectionSource extends AbstractConnectionSource {

    /**
     * Builds DriverManagerConnectionSource instances.
     *
     * @param <B>
     *            This builder type or a subclass.
     */
    public static class Builder<B extends Builder<B>> {

        @PluginBuilderAttribute
        @Required
        protected String connectionString;

        @PluginBuilderAttribute
        protected String driverClassName;

        @PluginBuilderAttribute
        protected char[] password;

        @PluginElement("Properties")
        protected Property[] properties;

        @PluginBuilderAttribute
        protected char[] userName;

        @SuppressWarnings("unchecked")
        protected B asBuilder() {
            return (B) this;
        }

        public String getConnectionString() {
            return connectionString;
        }

        public String getDriverClassName() {
            return driverClassName;
        }

        public char[] getPassword() {
            return password;
        }

        public Property[] getProperties() {
            return properties;
        }

        public char[] getUserName() {
            return userName;
        }

        public B setConnectionString(final String connectionString) {
            this.connectionString = connectionString;
            return asBuilder();
        }

        public B setDriverClassName(final String driverClassName) {
            this.driverClassName = driverClassName;
            return asBuilder();
        }

        public B setPassword(final char[] password) {
            this.password = password;
            return asBuilder();
        }

        public B setProperties(final Property[] properties) {
            this.properties = properties;
            return asBuilder();
        }

        public B setUserName(final char[] userName) {
            this.userName = userName;
            return asBuilder();
        }
    }

    private static final Logger LOGGER = StatusLogger.getLogger();

    public static Logger getLogger() {
        return LOGGER;
    }

    private final String actualConnectionString;
    private final String connectionString;
    private final String driverClassName;
    private final char[] password;
    private final Property[] properties;
    private final char[] userName;

    public AbstractDriverManagerConnectionSource(final String driverClassName, final String connectionString,
            final String actualConnectionString, final char[] userName, final char[] password, final Property[] properties) {
        this.driverClassName = driverClassName;
        this.connectionString = connectionString;
        this.actualConnectionString = actualConnectionString;
        this.userName = userName;
        this.password = password;
        this.properties = properties;
    }

    public String getActualConnectionString() {
        return actualConnectionString;
    }

    @SuppressWarnings("resource") // The JDBC Connection is freed when the connection source is stopped.
    @Override
    public Connection getConnection() throws SQLException {
        loadDriver();
        final String actualConnectionString = getActualConnectionString();
        LOGGER.debug("{} getting connection for '{}'", getClass().getSimpleName(), actualConnectionString);
        Connection connection;
        if (properties != null && properties.length > 0) {
            if (userName != null || password != null) {
                throw new SQLException("Either set the userName and password, or set the Properties, but not both.");
            }
            connection = DriverManager.getConnection(actualConnectionString, toProperties(properties));
        } else {
            connection = DriverManager.getConnection(actualConnectionString, toString(userName), toString(password));
        }
        LOGGER.debug("{} acquired connection for '{}': {} ({}@{})", getClass().getSimpleName(), actualConnectionString,
                connection, connection.getClass().getName(), Integer.toHexString(connection.hashCode()));
        return connection;
    }

    public String getConnectionString() {
        return connectionString;
    }

    public String getDriverClassName() {
        return driverClassName;
    }

    public char[] getPassword() {
        return password;
    }

    public Property[] getProperties() {
        return properties;
    }

    public char[] getUserName() {
        return userName;
    }

    protected void loadDriver() throws SQLException {
        loadDriver(driverClassName);
    }

    /**
     * Loads a JDBC driver for the given class name
     *
     * @param className
     *            the fully-qualified class name for a JDBC Driver.
     * @throws SQLException
     *             thrown when loading the driver throws an exception.
     */
    protected void loadDriver(final String className) throws SQLException {
        if (className != null) {
            // Hack for old JDBC drivers.
            LOGGER.debug("Loading driver class {}", className);
            try {
                Class.forName(className);
            } catch (final Exception e) {
                throw new SQLException(String.format("The %s could not load the JDBC driver %s: %s",
                        getClass().getSimpleName(), className, e.toString()), e);
            }
        }
    }

    protected Properties toProperties(final Property[] properties) {
        final Properties props = new Properties();
        for (final Property property : properties) {
            props.setProperty(property.getName(), property.getValue());
        }
        return props;
    }

    @Override
    public String toString() {
        return this.connectionString;
    }

    protected String toString(final char[] value) {
        return value == null ? null : String.valueOf(value);
    }
}

⏎ org/apache/logging/log4j/core/appender/db/jdbc/AbstractDriverManagerConnectionSource.java

Or download all of them as a single archive file:

File name: log4j-core-2.14.1-sources.jar
File size: 1281358 bytes
Release date: 2021-03-06
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