Package migratedb.core.internal.util

Enum ClassUtils

java.lang.Object

java.lang.Enum<ClassUtils>

migratedb.core.internal.util.ClassUtils

All Implemented Interfaces:

Serializable, Comparable<ClassUtils>

public enum ClassUtils
extends Enum<ClassUtils>

Method Summary

Modifier and Type	Method	Description
static ClassLoader	defaultClassLoader()
static String	getClassName(@Nullable Object obj)
static String	getStaticFieldValue(Class<?> clazz, String fieldName)	Gets the String value of a static field.
static String	getStaticFieldValue(String className, String fieldName, ClassLoader classLoader)	Gets the String value of a static field.
static Path	guessLocationOnDisk(Class<?> aClass)	Tries to get the physical location on disk of aClass.
static <T> T	instantiate(Class<T> clazz)	Creates a new instance of clazz.
static <T> T	instantiate(String className, ClassLoader classLoader)	Creates a new instance of this class.
static <T> List<T>	instantiateAll(String[] classes, ClassLoader classLoader)	Instantiate all these classes.
static <E extends Exception> Object	invoke(Class<?> clazz, String methodName, Object receiver, Class<?>[] paramTypes, Object[] params, Function<? super Throwable,@Nullable E> exceptionMapper)
static boolean	isImplementationPresent(String serviceName, ClassLoader classLoader)	Determine whether a class implementing the service identified by the supplied name is present and can be loaded.
static boolean	isPresent(String className, ClassLoader classLoader)	Determine whether the Class identified by the supplied name is present and can be loaded.
static Class<?>	loadClass(String className, ClassLoader classLoader)	Loads className using the class loader.
static ClassUtils	valueOf(String name)	Returns the enum constant of this type with the specified name.
static ClassUtils[]	values()	Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Method Detail

values

public static ClassUtils[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (ClassUtils c : ClassUtils.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static ClassUtils valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

NullPointerException - if the argument is null

instantiate

public static <T> T instantiate(String className,
                                ClassLoader classLoader)

Creates a new instance of this class.

Type Parameters:

T - The type of the new instance.

Parameters:

className - The fully qualified name of the class to instantiate.

classLoader - The ClassLoader to use.

Returns:

The new instance.

Throws:

MigrateDbException - Thrown when the instantiation failed.

instantiate

public static <T> T instantiate(Class<T> clazz)

Creates a new instance of clazz.

Type Parameters:

T - The type of the new instance.

Returns:

The new instance.

Throws:

MigrateDbException - Thrown when the instantiation failed.

instantiateAll

public static <T> List<T> instantiateAll(String[] classes,
                                         ClassLoader classLoader)

Instantiate all these classes.

Type Parameters:

T - The common type for all classes.

Parameters:

classes - Fully qualified class names to instantiate.

classLoader - The ClassLoader to use.

Returns:

The list of instances.

isPresent

public static boolean isPresent(String className,
                                ClassLoader classLoader)

Determine whether the Class identified by the supplied name is present and can be loaded. Will return false if either the class or one of its dependencies is not present or cannot be loaded.

Parameters:

className - The name of the class to check.

classLoader - The ClassLoader to use.

Returns:

whether the specified class is present

isImplementationPresent

public static boolean isImplementationPresent(String serviceName,
                                              ClassLoader classLoader)

Determine whether a class implementing the service identified by the supplied name is present and can be loaded. Will return false if either no class is found, or the class or one of its dependencies is not present or cannot be loaded.

Parameters:

serviceName - The name of the service to check.

classLoader - The ClassLoader to use.

Returns:

whether an implementation of the specified service is present

loadClass

public static Class<?> loadClass(String className,
                                 ClassLoader classLoader)

Loads className using the class loader.

Parameters:

className - The name of the class to load.

classLoader - The ClassLoader to use.

Returns:

the newly loaded class

guessLocationOnDisk

public static Path guessLocationOnDisk(Class<?> aClass)

Tries to get the physical location on disk of aClass.

Parameters:

aClass - The class to get the location for.

Returns:

The absolute path of the .class file (or null).

getStaticFieldValue

public static String getStaticFieldValue(String className,
                                         String fieldName,
                                         ClassLoader classLoader)

Gets the String value of a static field.

Parameters:

className - The fully qualified name of the class to instantiate.

classLoader - The ClassLoader to use.

fieldName - The field name

Returns:

The value of the field.

Throws:

MigrateDbException - If the field value cannot be read.

getStaticFieldValue

public static String getStaticFieldValue(Class<?> clazz,
                                         String fieldName)

Gets the String value of a static field.

Throws:

MigrateDbException - If the field value cannot be read.

defaultClassLoader

public static ClassLoader defaultClassLoader()

Returns:

The first class loader that is non-null:

1. Thread context class loader
2. Class loader of this class
3. System class loader

invoke

public static <E extends Exception> Object invoke(Class<?> clazz,
                                                  String methodName,
                                                  Object receiver,
                                                  Class<?>[] paramTypes,
                                                  Object[] params,
                                                  Function<? super Throwable,@Nullable E> exceptionMapper)
                                           throws E extends Exception

Throws:

E extends Exception

getClassName

public static String getClassName(@Nullable Object obj)