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Is there an alternate way of doing the same thing? It obtains a reference to the class object with the FQCN fully qualified class name oracle. It doesn't "do" anything in terms of connecting to a database, aside from ensure that the specified class is loaded by the current classloader.
There is no fundamental difference between writing. From The Java Tutorial :. This methods required an object of type java. Each JDBC driver contains one or more classes that implements the interface java.
Any JDBC 4. However, you must manually load any drivers prior to JDBC 4. So, if you're using the Oracle 11g Otherwise, you need to call it to initialise the driver. This command loads class of Oracle jdbc driver to be available for DriverManager instance. After the class is loaded system can connect to Oracle using it.
An alternative would to use the jdbc. Use oracle. OracleDriver, not oracle. Save this as test. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. What is the actual use of Class. OracleDriver" while connecting to a database? Ask Question.
Asked 10 years ago. Active 4 years, 6 months ago. Viewed k times. After you've installed the appropriate driver, it is time to establish a database connection using JDBC. The programming involved to establish a JDBC connection is fairly simple. The Import statements tell the Java compiler where to find the classes you reference in your code and are placed at the very beginning of your source code.
You must register the driver in your program before you use it. Registering the driver is the process by which the Oracle driver's class file is loaded into the memory, so it can be utilized as an implementation of the JDBC interfaces. You need to do this registration only once in your program. You can register a driver in one of two ways.
The most common approach to register a driver is to use Java's Class. This method is preferable because it allows you to make the driver registration configurable and portable.
The second approach you can use to register a driver, is to use the static DriverManager. After you've loaded the driver, you can establish a connection using the DriverManager. Also, using Class. If, for example, the person compiling the code does not for, let's say, licensing or intellectual property reasons have access to the class oracle.
OracleDriver, they may find it easier to compile code which references the class by Class. If you do not need to use any methods, fields, or inner classes of the specified class, then Class. I don't think Class. It uses the calling class' classloader by default, which should be the same classloader that is used when referencing the class directly.
There are some overloads to Class. Sometimes it is required to load a class during the run time. The Class. For example, when we use IDE, we see there will be a GUI builder which allows us to drag and drop the buttons, text fields, etc. This drag and drop mechanism internally requires certain classes to be loaded at run time.
In the Class. JdbcOdbcDriver , the Class belongs to the package java. Class and the forName is a static method of the java. The JDBC Drivers String will be loaded into the class dynamically at run time and forName method contains static block which creates the Driver class object and register with the DriverManager Service automatically.
Since the forName is static, we call it using the class name Class. When we want to execute static block of a class, without creating its object then we can use class. Most of the work that Driver class do, exists in its static block.
Now what we require in our JDBC connectivity is to get the driver registered with DriverManager and to obtain connections with it, so this can be achieved simply by getting static block executed and there is no requirement to create object of that class.
This approach will give a better performance. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow.
Learn more. Why we use Class. Ask Question. Asked 7 years, 11 months ago. Active 1 year, 1 month ago. Viewed 47k times. Improve this question. Mark Rotteveel 86k gold badges silver badges bronze badges.
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