net.yetamine.osgi.jdbc.support.DriverReference Maven / Gradle / Ivy
/*
* Copyright 2016 Yetamine
*
* 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 net.yetamine.osgi.jdbc.support;
import java.sql.Driver;
import java.util.Objects;
/**
* Reference to a driver.
*
*
* This class allows to avoid using the driver's {@link Object#equals(Object)}
* and {@link Object#hashCode()} methods which might be misleading or harmful.
* Two instances of this class are hence equal only if they refer to the same
* driver instance.
*/
public final class DriverReference {
/** Represented driver. */
private final Driver driver;
/**
* Creates a new instance.
*
* @param instance
* the driver instance. It must not be {@code null}.
*/
public DriverReference(Driver instance) {
driver = Objects.requireNonNull(instance);
}
/**
* @see java.lang.Object#equals(java.lang.Object)
*/
@Override
public boolean equals(Object obj) {
return (obj instanceof DriverReference) && (driver == ((DriverReference) obj).driver);
}
/**
* @see java.lang.Object#hashCode()
*/
@Override
public int hashCode() {
return driver.hashCode();
}
/**
* @see java.lang.Object#toString()
*/
@Override
public String toString() {
final String f = "Driver[class=%s, version=%s, id=%08x]";
return String.format(f, driverClass().getTypeName(), driverVersion(), System.identityHashCode(driver));
}
/**
* Returns the driver class name.
*
* @return the driver class
*/
public Class driverClass() {
return driver.getClass();
}
/**
* Returns the driver version as reported by the driver as a {@link String}
* in the format major.minor
*
* @return the driver version
*/
public String driverVersion() {
return String.format("%d.%d", driver.getMajorVersion(), driver.getMinorVersion());
}
/**
* Returns the driver.
*
* @return the driver
*/
public Driver driver() {
return driver;
}
}