Module org.apache.sis.metadata
Package org.apache.sis.xml

Class XLink

Object
XLink
All Implemented Interfaces:
Serializable
public class XLink extends Object implements Serializable
The XML attributes defined by OGC in the xlink schema. The allowed combinations of any one attribute depend on the value of the special type attribute. Following is a summary of the element types (columns) on which the global attributes (rows) are allowed, with an indication of whether a value is required (R) or optional (O) (Source: W3C):
XLink attribute usage patterns
  simple extended locator arc resource title
type RRRRRR
href O R   
role OOO O 
arcrole O  O  
title OOOOO 
show O  O  
actuate O  O  
label   O O 
from    O  
to    O  
When xlink attributes are found at unmarshalling time instead of an object definition, those attributes are given to the Reference­Resolver​.resolve(Marshal­Context, Class, XLink) method. Users can override that method in order to fetch an instance in some catalog for the given xlink values.
Since:
0.3
See Also:

  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Class
    Description
    static enum 
    XLink​.Actuate
    Communicates the desired timing of traversal from the starting resource to the ending resource.
    static enum 
    XLink​.Show
    Communicates the desired presentation of the ending resource on traversal from the starting resource.
    static enum 
    XLink​.Type
    The type of a xlink.

  • Constructor Summary

    Constructors
    Constructor
    Description
    XLink()
    Creates a new link.
    XLink(XLink link)
    Creates a new link as a copy of the given link.

  • Method Summary

    Modifier and Type
    Method
    Description
    boolean
    equals(Object object)
    Compares this XLink with the given object for equality.
    void
    freeze()
    Marks this xlink as unmodifiable.
    XLink​.Actuate
    get­Actuate()
    Returns the desired timing of traversal from the starting resource to the ending resource.
    URI
    get­Arc­Role()
    Returns a URI reference for some description of the arc role.
    String
    get­From()
    Returns the starting resource.
    URI
    get­HRef()
    Returns a URN to an external resources, or to another part of a XML document, or an identifier.
    String
    get­Label()
    Returns an identification of the target of a from or to attribute.
    URI
    get­Role()
    Returns a URI reference for some description of the arc role.
    XLink​.Show
    get­Show()
    Returns the desired presentation of the ending resource on traversal from the starting resource.
    International­String
    get­Title()
    Returns a human-readable string with a short description for the arc.
    String
    get­To()
    Returns the ending resource.
    XLink​.Type
    get­Type()
    Returns the type of link.
    int
    hash­Code()
    Returns a hash code value for this XLink.
    void
    set­Actuate(XLink​.Actuate actuate)
    Sets the desired timing of traversal from the starting resource to the ending resource.
    void
    set­Arc­Role(URI arcrole)
    Sets a URI reference for some description of the arc role.
    void
    set­From(String from)
    Sets the starting resource.
    void
    set­HRef(URI href)
    Sets the URN to a resources.
    void
    set­Label(String label)
    Sets an identification of the target of a from or to attribute.
    void
    set­Role(URI role)
    Sets the URI reference for some description of the arc role.
    void
    set­Show(XLink​.Show show)
    Sets the desired presentation of the ending resource on traversal from the starting resource.
    void
    set­Title(International­String title)
    Sets a human-readable string with a short description for the arc.
    void
    set­To(String to)
    Sets the ending resource.
    void
    set­Type(XLink​.Type type)
    Sets the type of link.
    String
    to­String()
    Returns a string representation of this object.

    Methods inherited from class Object

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

  • Constructor Details

    • XLink

      public XLink()
      Creates a new link. The initial value of all attributes is null.

    • XLink

      public XLink(XLink link)
      Creates a new link as a copy of the given link.
      Parameters:
      link - The link to copy, or null if none.

  • Method Details

    • getType

      public XLink.Type getType()
      Returns the type of link. May have one of the following values:
      • simple: a simple link
      • extended: an extended, possibly multi-resource, link
      • locator: a pointer to an external resource
      • resource: an internal resource
      • arc: a traversal rule between resources
      • title: a descriptive title for another linking element
      The default value is null. If the set­Type(XLink​.Type) method has been invoked with the AUTO enum, then this method will infer a type from the attributes having a non-null value.
      Returns:
      the type of link, or null.

    • setType

      public void setType(XLink.Type type)
      Sets the type of link. Any value different than Type​.AUTO (including null) will overwrite the value inferred automatically by get­Type(). A AUTO value will enable automatic type detection.
      Parameters:
      type - the new type of link, or null if none.

    • getHRef

      public URI getHRef()
      Returns a URN to an external resources, or to another part of a XML document, or an identifier.
      Returns:
      a URN to a resources, or null if none.

    • setHRef

      public void setHRef(URI href) throws IllegalStateException
      Sets the URN to a resources.
      Parameters:
      href - a URN to a resources, or null if none.
      Throws:
      Unsupported­Operation­Exception - if this xlink is unmodifiable.
      Illegal­State­Exception - if the link type has been explicitly set. and that type does not allow the "href" attribute.

    • getRole

      public URI getRole()
      Returns a URI reference for some description of the arc role.
      Returns:
      a URI reference for some description of the arc role, or null if none.

    • setRole

      public void setRole(URI role) throws IllegalStateException
      Sets the URI reference for some description of the arc role.
      Parameters:
      role - a URI reference for some description of the arc role, or null if none.
      Throws:
      Unsupported­Operation­Exception - if this xlink is unmodifiable.
      Illegal­State­Exception - if the link type has been explicitly set. and that type does not allow the "role" attribute.

    • getArcRole

      public URI getArcRole()
      Returns a URI reference for some description of the arc role.
      Returns:
      a URI reference for some description of the arc role, or null if none.

    • setArcRole

      public void setArcRole(URI arcrole) throws IllegalStateException
      Sets a URI reference for some description of the arc role.
      Parameters:
      arcrole - a URI reference for some description of the arc role, or null if none.
      Throws:
      Unsupported­Operation­Exception - if this xlink is unmodifiable.
      Illegal­State­Exception - if the link type has been explicitly set. and that type does not allow the "arcrole" attribute.

    • getTitle

      public InternationalString getTitle()
      Returns a human-readable string with a short description for the arc.
      Returns:
      a human-readable string with a short description for the arc, or null if none.

    • setTitle

      public void setTitle(InternationalString title) throws IllegalStateException
      Sets a human-readable string with a short description for the arc.
      Parameters:
      title - a human-readable string with a short description for the arc, or null if none.
      Throws:
      Unsupported­Operation­Exception - if this xlink is unmodifiable.
      Illegal­State­Exception - if the link type has been explicitly set. and that type does not allow the "title" attribute.

    • getShow

      public XLink.Show getShow()
      Returns the desired presentation of the ending resource on traversal from the starting resource. It's value should be treated as follows:
      • new: load ending resource in a new window, frame, pane, or other presentation context
      • replace: load the resource in the same window, frame, pane, or other presentation context
      • embed: load ending resource in place of the presentation of the starting resource
      • other: behavior is unconstrained; examine other markup in the link for hints
      • none: behavior is unconstrained
      Returns:
      the desired presentation of the ending resource, or null if unspecified.

    • setShow

      public void setShow(XLink.Show show) throws IllegalStateException
      Sets the desired presentation of the ending resource on traversal from the starting resource.
      Parameters:
      show - the desired presentation of the ending resource, or null if unspecified.
      Throws:
      Unsupported­Operation­Exception - if this xlink is unmodifiable.
      Illegal­State­Exception - if the link type has been explicitly set. and that type does not allow the "show" attribute.

    • getActuate

      public XLink.Actuate getActuate()
      Returns the desired timing of traversal from the starting resource to the ending resource. It's value should be treated as follows:
      • onLoad: traverse to the ending resource immediately on loading the starting resource
      • onRequest: traverse from the starting resource to the ending resource only on a post-loading event triggered for this purpose
      • other: behavior is unconstrained; examine other markup in link for hints
      • none: behavior is unconstrained
      Returns:
      the desired timing of traversal from the starting resource to the ending resource, or null if unspecified.

    • setActuate

      public void setActuate(XLink.Actuate actuate) throws IllegalStateException
      Sets the desired timing of traversal from the starting resource to the ending resource.
      Parameters:
      actuate - the desired timing of traversal from the starting resource to the ending resource, or null if unspecified.
      Throws:
      Unsupported­Operation­Exception - if this xlink is unmodifiable.
      Illegal­State­Exception - if the link type has been explicitly set. and that type does not allow the "actuate" attribute.

    • getLabel

      public String getLabel()
      Returns an identification of the target of a from or to attribute.
      Returns:
      an identification of the target of a from or to attribute, or null.

    • setLabel

      public void setLabel(String label) throws IllegalStateException
      Sets an identification of the target of a from or to attribute.
      Parameters:
      label - an identification of the target of a from or to attribute, or null.
      Throws:
      Unsupported­Operation­Exception - if this xlink is unmodifiable.
      Illegal­State­Exception - if the link type has been explicitly set. and that type does not allow the "label" attribute.

    • getFrom

      public String getFrom()
      Returns the starting resource. The value must correspond to the same value for some label attribute.
      Returns:
      the starting resource, or null.

    • setFrom

      public void setFrom(String from) throws IllegalStateException
      Sets the starting resource. The value must correspond to the same value for some label attribute.
      Parameters:
      from - the starting resource, or null.
      Throws:
      Unsupported­Operation­Exception - if this xlink is unmodifiable.
      Illegal­State­Exception - if the link type has been explicitly set. and that type does not allow the "from" attribute.

    • getTo

      public String getTo()
      Returns the ending resource. The value must correspond to the same value for some label attribute.
      Returns:
      the ending resource, or null.

    • setTo

      public void setTo(String to) throws IllegalStateException
      Sets the ending resource. The value must correspond to the same value for some label attribute.
      Parameters:
      to - the ending resource, or null.
      Throws:
      Unsupported­Operation­Exception - if this xlink is unmodifiable.
      Illegal­State­Exception - if the link type has been explicitly set. and that type does not allow the "to" attribute.

    • freeze

      public void freeze()
      Marks this xlink as unmodifiable. After this method call, any call to a setter method will throw an Unsupported­Operation­Exception.

      After the first call to this method, any subsequent calls have no effect.

    • equals

      public boolean equals(Object object)
      Compares this XLink with the given object for equality.
      Overrides:
      equals in class Object
      Parameters:
      object - the object to compare with this XLink.

    • hashCode

      public int hashCode()
      Returns a hash code value for this XLink.
      Overrides:
      hash­Code in class Object

    • toString

      public String toString()
      Returns a string representation of this object. The default implementation returns the simple class name followed by non-null attributes, as in the example below: 
      XLink[type="locator", href="urn:ogc:def:method:EPSG::4326"]
      Overrides:
      to­String in class Object