org.arp.javautil.sql.DataSourceConnectionSpec Maven / Gradle / Ivy

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/*
 * #%L
 * JavaUtil
 * %%
 * Copyright (C) 2012 - 2013 Emory University
 * %%
 * 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.
 * #L%
 */
package org.arp.javautil.sql;

import java.sql.Connection;
import java.sql.SQLException;
import java.util.Hashtable;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.sql.DataSource;

/**
 * Implements getting a connection to a relational database using Java's
 * {@link DataSource} API.
 *
 * @author Andrew Post
 * @see InitialContext
 */
public class DataSourceConnectionSpec extends AbstractConnectionSpec {

    private final String user;
    private final String password;
    private final DataSource dataSource;

    /**
     * Creates an instance that will get connections from the database with the
     * specified JNDI name.
     *
     * @param jndiName a JNDI name {@link String}.
     * @throws NamingException if the specified JNDI name is invalid.
     */
    public DataSourceConnectionSpec(String jndiName, boolean autoCommitEnabled) throws NamingException {
        this(jndiName, null, null, autoCommitEnabled);
    }
    
    public DataSourceConnectionSpec(String jndiName) throws NamingException {
        this(jndiName, null, null);
    }

    /**
     * Creates an instance that will get connections from the database with the
     * specified JNDI name using the specified username and password. No
     * environment properties are supplied when looking up the JNDI name. See
     * the javadoc for {@link InitialContext} for a description of environment
     * properties.
     *
     * @param jndiName a JNDI name {@link String}.
     * @param user a username {@link String}.
     * @param password a password {@link String}.
     * @throws NamingException if an error occurs during JNDI lookup.
     */
    public DataSourceConnectionSpec(String jndiName,
            String user, String password, boolean autoCommitEnabled) throws NamingException {
        this(jndiName, null, user, password, autoCommitEnabled);
    }
    
    public DataSourceConnectionSpec(String jndiName,
            String user, String password) throws NamingException {
        this(jndiName, null, user, password);
    }
    
    public DataSourceConnectionSpec(String jndiName,
            Hashtable environment,
            String user, String password) throws NamingException {
        this(jndiName, environment, user, password, true);
    }

    /**
     * Creates an instance that will get connections from the database with the
     * specified JNDI name using the specified username and password. The
     * specified environment will be used when looking up the JNDI name. See the
     * javadoc for {@link InitialContext} for a description of environment
     * properties.
     *
     * @param jndiName a JNDI name {@link String}.
     * @param environment a {@link Hashtable} of environment properties.
     * @param user a username {@link String}.
     * @param password a password {@link String}.
     * @throws NamingException if an error occurs during JNDI lookup.
     */
    public DataSourceConnectionSpec(String jndiName,
            Hashtable environment,
            String user, String password, boolean autoCommitEnabled) throws NamingException {
        super(autoCommitEnabled);
        if (jndiName == null) {
            throw new IllegalArgumentException("jndiName cannot be null");
        }
        this.user = user;
        this.password = password;

        InitialContext ctx = new InitialContext(environment);
        try {
            this.dataSource = (DataSource) ctx.lookup(jndiName);
        } finally {
            ctx.close();
        }
    }

    /**
     * Creates a database connection or gets an existing connection with the
     * JNDI name, username and password specified in the constructor.
     *
     * @return a {@link Connection}.
     *
     * @throws SQLException if an error occurred creating/getting a
     * {@link Connection}, possibly because the JNDI name, username and/or
     * password are invalid.
     */
    @Override
    public Connection getOrCreate() throws SQLException {
        Connection con;
        if (this.user == null && this.password == null) {
            con = this.dataSource.getConnection();
        } else {
            con = this.dataSource.getConnection(this.user, this.password);
        }
        con.setAutoCommit(isAutoCommitEnabled());
        return con;
    }

    /**
     * Gets the specified data source.
     *
     * @return a {@link DataSource}.
     */
    public DataSource getDataSource() {
        return this.dataSource;
    }

    @Override
    public void accept(ConnectionSpecVisitor connectionSpecVisitor) {
        connectionSpecVisitor.visit(this);
    }

}