org.incava.ijdk.lang

Class Obj<T>

java.lang.Object

org.incava.ijdk.lang.Obj<T>

Type Parameters:

T - the type of object being wrapped

All Implemented Interfaces:

Bool

Direct Known Subclasses:

Int, Str

public class Obj<T>
extends java.lang.Object
implements Bool

Extension to the Object class, wrapping a JDK Object with additional methods. The referenced object can be null. Also has "boolean-ness" of an object, which can be true, false, or empty.

Field Summary

Fields

Modifier and Type	Field and Description
static Obj<java.lang.Object>	NULL A single variable representing all objects that wrap null.

Constructor Summary

Constructors

Constructor and Description
Obj(T object) Creates a wrapper for the given object.

Method Summary

Modifier and Type	Method and Description
boolean	equals(java.lang.Object other) Returns whether the other object is equal to the wrapped object, including whether they are both null.
T	get() Returns the wrapped object.
int	hashCode() Returns the hash code of the wrapped object.
boolean	isEmpty() Returns whether the wrapped object is null or is a string or collection of zero length.
boolean	isFalse() Returns whether the wrapped object is null or is a string or collection of zero length.
boolean	isNotNull() Returns whether the wrapped object is not null.
boolean	isNull() Returns whether the wrapped object is null.
boolean	isTrue() Returns whether the wrapped object is non-null and, if it is a collection or a string, has a length greater than zero.
T	obj() Returns the wrapped object.
static <T> Obj<T>	of(T obj) Creates a wrapper for the given object.
java.lang.String	toString() Returns the wrapped object as a string.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

NULL

public static Obj<java.lang.Object> NULL

A single variable representing all objects that wrap null.

Constructor Detail

Obj

public Obj(T object)

Creates a wrapper for the given object.

Parameters:

object - the object to wrap

Method Detail

of

public static <T> Obj<T> of(T obj)

Creates a wrapper for the given object. If the object is null, the common variable NULL is returned, thus eliminating unnecessary object creation.

Type Parameters:

T - the type of object being wrapped

Parameters:

obj - the object being wrapped

Returns:

the newly created object, or NULL

get

public T get()

Returns the wrapped object.

Returns:

the wrapped object

See Also:

obj()

obj

public T obj()

Returns the wrapped object.

Returns:

the wrapped object

See Also:

get()

equals

public boolean equals(java.lang.Object other)

Returns whether the other object is equal to the wrapped object, including whether they are both null. If other is a Obj, then its wrapped object is compared.

Overrides:

equals in class java.lang.Object

Parameters:

other - the object to compare to the wrapped object

Returns:

whether the given object equals this one

hashCode

public int hashCode()

Returns the hash code of the wrapped object. Returns 0 if the referenced object is null.

Overrides:

hashCode in class java.lang.Object

Returns:

the hash code

isTrue

public boolean isTrue()

Returns whether the wrapped object is non-null and, if it is a collection or a string, has a length greater than zero.

Specified by:

isTrue in interface Bool

Returns:

whether the wrapped object is not null and is true for that object type

See Also:

isEmpty(), isFalse()

isFalse

public boolean isFalse()

Returns whether the wrapped object is null or is a string or collection of zero length.

Specified by:

isFalse in interface Bool

Returns:

whether the wrapped object is null or is false for that object type

See Also:

isEmpty(), isTrue()

isEmpty

public boolean isEmpty()

Returns whether the wrapped object is null or is a string or collection of zero length.

Specified by:

isEmpty in interface Bool

Returns:

whether the wrapped object is null or is empty for that object type

See Also:

isEmpty(), isFalse()

isNull

public boolean isNull()

Returns whether the wrapped object is null. This method provides an alternative syntax to "if (obj == null)".

Returns:

whether the wrapped object is null

See Also:

isNotNull()

isNotNull

public boolean isNotNull()

Returns whether the wrapped object is not null. This method provides an alternative syntax to "if (obj != null)".

Returns:

whether the wrapped object is not null

See Also:

isNull()

toString

public java.lang.String toString()

Returns the wrapped object as a string. C style arrays (e.g., Double[]) are run through the toString for java.util.List, giving them better output, "[abc, def, ghi]" instead of "[Ljava.lang.Object;@15db9742".

Overrides:

toString in class java.lang.Object