com.scvngr.levelup.core.util

Class NullUtils

java.lang.Object

com.scvngr.levelup.core.util.NullUtils

@LevelUpApi(contract=INTERNAL)
public final class NullUtils
extends Object

Utilities to help use NonNull and Nullable annotations.

Method Summary

Modifier and Type	Method and Description
static String	format(Locale locale, String format, Object... args) A wrapper around String.format(Locale, String, Object...) which returns a non-null result and uses Locale.US.
static String	format(String format, Object... args) A wrapper around String.format(Locale, String, Object...) which returns a non-null result and uses Locale.US.
static String	getClassName(Class<?> clazz)
static <T> T	nonNullContract(T source) Retrieves a non-null result from source or throws an exception if the source is null.
static <T> T	nonNullContract(T source, String what) Retrieves a non-null result from source or throws an exception if the source is null.

Methods inherited from class java.lang.Object

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

Method Detail

nonNullContract

public static <T> T nonNullContract(T source,
                                    String what)

Retrieves a non-null result from source or throws an exception if the source is null. This should be used when the wrapped source claims to return non-null, but isn't annotated.

Type Parameters:

T - type of object to return.

Parameters:

source - source object or null.

what - a human-readable identifier for the item.

Returns:

the source object.

Throws:

AssertionError - if the source is null

nonNullContract

public static <T> T nonNullContract(T source)

Retrieves a non-null result from source or throws an exception if the source is null. This should be used when the wrapped source claims to return non-null, but isn't annotated.

Type Parameters:

T - type of object to return.

Parameters:

source - source object or null.

Returns:

the source object.

Throws:

AssertionError - if the source is null

getClassName

public static String getClassName(Class<?> clazz)

Parameters:

clazz - the class whose name is being retrieved

Returns:

the value of class.getName()

format

public static String format(String format,
                            Object... args)

A wrapper around String.format(Locale, String, Object...) which returns a non-null result and uses Locale.US.

Parameters:

format - format string

args - optional arguments

Returns:

a non-null formatted string

format

public static String format(Locale locale,
                            String format,
                            Object... args)

A wrapper around String.format(Locale, String, Object...) which returns a non-null result and uses Locale.US.

Parameters:

locale - format locale

format - format string

args - optional arguments

Returns:

a non-null formatted string