org.unix4j.util

Class Java7Util

java.lang.Object

org.unix4j.util.Java7Util

public class Java7Util
extends Object

Utility class with static methods to help loading a Java 7 version of a class if it is available, and the Java 6 version otherwise.

Field Summary

Fields

Modifier and Type	Field and Description
static String	JAVA7_CLASS_NAME_SUFFIX The suffix used for Java 7 classes, the string "7".

Constructor Summary

Constructors

Constructor and Description
Java7Util()

Method Summary

Methods

Modifier and Type	Method and Description
static <T> Class<? extends T>	loadClass(Class<T> baseClass) Returns the Java 7 version of the given class if it exists and can be loaded, and the given baseClass otherwise.
static <T> T	newInstance(Class<T> baseClass, T defaultInstance) Returns a new instance of the Java 7 version of the given class if it exists and can be instantiated.

Methods inherited from class java.lang.Object

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

Field Detail

JAVA7_CLASS_NAME_SUFFIX

public static final String JAVA7_CLASS_NAME_SUFFIX

The suffix used for Java 7 classes, the string "7".

See Also:

Constant Field Values

Constructor Detail

Java7Util

public Java7Util()

Method Detail

newInstance

public static <T> T newInstance(Class<T> baseClass,
                T defaultInstance)

Returns a new instance of the Java 7 version of the given class if it exists and can be instantiated. Otherwise, the given defaultInstance is returned.

The Java 7 version of the class must be a subtype of baseClass and its fully qualified name must be identical to that of baseClass with a suffix "7". For instance, if the Java 6 base class is called "org.unix4j.MyClass", the Java 7 version must be called "org.unix4j.MyClass7". Furthermore, the class must have a default constructor with no arguments.

If the Java 7 version of the class is not found (usually because unix4j was compiled with a Java 6 compiler) or if the Java 7 class cannot be instantiated (usually because unix4j is run in a Java 6 JVM), the given defaultInstance is returned.

Type Parameters:

T - the generic return type

Parameters:

baseClass - the base class and superclass of the Java 7 class

Returns:

a new instance of the Java 7 subtype if possible and defaultInstance otherwise

loadClass

public static <T> Class<? extends T> loadClass(Class<T> baseClass)

Returns the Java 7 version of the given class if it exists and can be loaded, and the given baseClass otherwise.

The Java 7 version of the class must be a subtype of baseClass and its fully qualified name must be identical to that of baseClass with a suffix "7". For instance, if the Java 6 base class is called "org.unix4j.MyClass", the Java 7 version must be called "org.unix4j.MyClass7".

If the Java 7 version of the class is not found (usually because unix4j was compiled with a Java 6 compiler), the given defaultInstance is returned. If the class is found but it is not a subtype of the given baseClass, an exception is thrown.

Type Parameters:

T - the generic type of the base class

Parameters:

baseClass - the base class and superclass of the Java 7 class

Returns:

the Java 7 subclass if possible and baseClass otherwise

Throws:

NullPointerException - if baseClass is null

IllegalArgumentException - if the Java 7 class is found but it is not a subclass of baseClass