org.openide.util

Class Lookup.Template<T>

java.lang.Object

org.openide.util.Lookup.Template<T>

Enclosing class:

Lookup

public static final class Lookup.Template<T>
extends Object

Template defining a pattern to filter instances by.

Constructor Summary

Constructors

Constructor and Description
Template() Deprecated. Use new Template (Object.class) which is going to be better typed with JDK1.5 templates and should produce the same result.
Template(Class<T> type) Create a simple template matching by class.
Template(Class<T> type, String id, T instance) Constructor to create new template.

Method Summary

Modifier and Type	Method and Description
boolean	equals(Object obj) Indicates whether some other object is "equal to" this one.
String	getId() Get the persistent identifier being searched for, if any.
T	getInstance() Get the specific instance being searched for, if any.
Class<T>	getType() Get the class (or superclass or interface) to search for.
int	hashCode() Returns a hash code value for the object.
String	toString() Returns a string representation of the object.

Methods inherited from class java.lang.Object

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

Constructor Detail

Template

@Deprecated
public Template()

Deprecated. Use new Template (Object.class) which is going to be better typed with JDK1.5 templates and should produce the same result.

General template to find all possible instances.

Template

public Template(Class<T> type)

Create a simple template matching by class.

Parameters:

type - the class of service we are looking for (subclasses will match)

Template

public Template(Class<T> type,
                String id,
                T instance)

Constructor to create new template.

Parameters:

type - the class of service we are looking for or null to leave unspecified

id - the ID of the item/service we are looking for or null to leave unspecified

instance - a specific known instance to look for or null to leave unspecified

Method Detail

getType

public Class<T> getType()

Get the class (or superclass or interface) to search for. If it was not specified in the constructor, Object is used as this will match any instance.

Returns:

the class to search for

getId

public String getId()

Get the persistent identifier being searched for, if any.

Returns:

the ID or null

Since:

1.8

See Also:

Lookup.Item.getId()

getInstance

public T getInstance()

Get the specific instance being searched for, if any. Most useful for finding an Item when the instance is already known.

Returns:

the object to find or null

Since:

1.8

hashCode

public int hashCode()

Description copied from class: Object

Returns a hash code value for the object. This method is supported for the benefit of hash tables such as those provided by HashMap.

The general contract of hashCode is:

• Whenever it is invoked on the same object more than once during an execution of a Java application, the hashCode method must consistently return the same integer, provided no information used in equals comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application.
• If two objects are equal according to the equals(Object) method, then calling the hashCode method on each of the two objects must produce the same integer result.
• It is not required that if two objects are unequal according to the Object.equals(java.lang.Object) method, then calling the hashCode method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables.

As much as is reasonably practical, the hashCode method defined by class Object does return distinct integers for distinct objects. (This is typically implemented by converting the internal address of the object into an integer, but this implementation technique is not required by the Java^TM programming language.)

Overrides:

hashCode in class Object

Returns:

a hash code value for this object.

See Also:

Object.equals(java.lang.Object), System.identityHashCode(java.lang.Object)

equals

public boolean equals(Object obj)

Description copied from class: Object

Indicates whether some other object is "equal to" this one.

The equals method implements an equivalence relation on non-null object references:

• It is reflexive: for any non-null reference value x, x.equals(x) should return true.
• It is symmetric: for any non-null reference values x and y, x.equals(y) should return true if and only if y.equals(x) returns true.
• It is transitive: for any non-null reference values x, y, and z, if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.
• It is consistent: for any non-null reference values x and y, multiple invocations of x.equals(y) consistently return true or consistently return false, provided no information used in equals comparisons on the objects is modified.
• For any non-null reference value x, x.equals(null) should return false.

The equals method for class Object implements the most discriminating possible equivalence relation on objects; that is, for any non-null reference values x and y, this method returns true if and only if x and y refer to the same object (x == y has the value true).

Note that it is generally necessary to override the hashCode method whenever this method is overridden, so as to maintain the general contract for the hashCode method, which states that equal objects must have equal hash codes.

Overrides:

equals in class Object

Parameters:

obj - the reference object with which to compare.

Returns:

true if this object is the same as the obj argument; false otherwise.

See Also:

Object.hashCode(), HashMap

toString

public String toString()

Description copied from class: Object

Returns a string representation of the object. In general, the toString method returns a string that "textually represents" this object. The result should be a concise but informative representation that is easy for a person to read. It is recommended that all subclasses override this method.

The toString method for class Object returns a string consisting of the name of the class of which the object is an instance, the at-sign character `@', and the unsigned hexadecimal representation of the hash code of the object. In other words, this method returns a string equal to the value of:

 getClass().getName() + '@' + Integer.toHexString(hashCode())
 

Overrides:

toString in class Object

Returns:

a string representation of the object.