Package org.postgresql.util

Class ClassUtils

java.lang.Object

org.postgresql.util.ClassUtils

public final class ClassUtils
extends Object

Utility class for safe class loading operations.

Method Summary

Modifier and Type	Method	Description
static <T> Class<? extends T>	forName(String className, Class<T> expectedClass, ClassLoader classLoader)	Deprecated. use forName(String, Class, ClassLoaderStrategy, ClassLoader), which also lets the caller fall back to the thread context classloader
static <T> Class<? extends T>	forName(String className, Class<T> expectedClass, ClassLoaderStrategy strategy, ClassLoader driverClassLoader)	Loads a class named by a connection property and validates that it is assignable to the expected type.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

forName

public static <T> Class<? extends T> forName(String className,
 Class<T> expectedClass,
 ClassLoaderStrategy strategy,
 ClassLoader driverClassLoader)
                                      throws ClassNotFoundException

Loads a class named by a connection property and validates that it is assignable to the expected type. The class is loaded with initialize=false so that its static initialiser does not run until the type check has passed.

The classloaders to try, and their order, come from strategy. The first classloader that resolves the name wins; a ClassNotFoundException from one classloader falls through to the next. A class that resolves but is not a subtype of expectedClass fails fast with a ClassCastException rather than falling through.

Type Parameters:

T - the expected type

Parameters:

className - the name of the class to load

expectedClass - the expected superclass or interface

strategy - the order in which to try the classloaders

driverClassLoader - the driver's own classloader

Returns:

the loaded class as a subclass of the expected type

Throws:

ClassNotFoundException - if none of the classloaders can find the class

forName

@Deprecated
public static <T> Class<? extends T> forName(String className,
 Class<T> expectedClass,
 ClassLoader classLoader)
                                      throws ClassNotFoundException

Deprecated.

use forName(String, Class, ClassLoaderStrategy, ClassLoader), which also lets the caller fall back to the thread context classloader

Loads a class by name from the given classloader only, validating that it is assignable to the expected type. A null classLoader means the bootstrap classloader, matching Class.forName(String, boolean, ClassLoader).

Type Parameters:

T - the expected type

Parameters:

className - the name of the class to load

expectedClass - the expected superclass or interface

classLoader - the classloader to use

Returns:

the loaded class as a subclass of the expected type

Throws:

ClassNotFoundException - if the class cannot be found