/* (c) 2014 Open Source Geospatial Foundation - all rights reserved
* (c) 2001 - 2013 OpenPlans
* This code is licensed under the GPL 2.0 license, available at the root
* application directory.
*/
package org.vfny.geoserver.global.xml;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;
/**
* NameSpaceTranslator purpose.
* <p>
* Helps perform translation between element names, definition names
* and their java types for a particular namespace and namespace prefix.
* </p>
* <p>
* Each name space translator should contain a list of name space
* elements for their particular prefix. This loading should not be
* completed lazily to avoid performance lags at run time. When ever
* posible constants should alos be used for performance purposes.
* </p>
* <p>
* USE:
* <code>
* NameSpaceTranslator nst = NameSpaceTranslatorFactor.getInstance().getNameSpaceTranslator("xs");
* Class cls = nst.getElement("string").getJavaClass();
* ...
* Object obj // contains some data, what can it be represented as?
* String elementName = ((NameSpaceElement)nst.getElements(obj).toArray()[0]).getTypeRefName();
* </code>
* </p>
* @author dzwiers, Refractions Research, Inc.
* @author $Author: dmzwiers $ (last modification)
* @version $Id$
*/
public abstract class NameSpaceTranslator {
/** the prefix for this translator instance*/
private String prefix;
/**
* NameSpaceTranslator constructor.
* <p>
* Creates an instance of this translator for the given prefix.
* </p>
* @param prefix The prefix for which this tranlator will tranlate.
* A null prefix will affect the NameSpaceElements returned by the
* access methods.
* @see #NameSpaceElement(String)
*/
public NameSpaceTranslator(String prefix) {
this.prefix = prefix;
}
/**
* Retrive all elements that can be used with the provided type.
* <p>
* Looks for Elements who's Class objects, or the parents of the
* Class object are compatible with this class object.
* </p>
* @param type Class the class to attempt to find related elements for.
* @return Set a set of associated NameSpaceElements
*/
public Set getAssociatedTypes(Class type) {
if (type == null) {
return null;
}
HashSet r = new HashSet();
Set elems = getElements();
Iterator i = elems.iterator();
while (i.hasNext()) {
NameSpaceElement nse = (NameSpaceElement) i.next();
if (nse != null) {
Class cls = nse.getJavaClass();
if ((cls != null) && cls.isAssignableFrom(type) && !cls.equals(Object.class)) {
r.add(nse);
}
}
}
return r;
}
/**
* Looks for Elements who's name is the same or a super set of this name.
* <p>
* (ie. name.indexOf(type)!=-1)
* </p>
* @param type String the class to attempt to find related elements for.
* @return Set a set of associated NameSpaceElements
* @see String#indexOf(String)
*/
public Set getAssociatedTypes(String type) {
if (type == null) {
return null;
}
HashSet r = new HashSet();
Set elems = getElements();
Iterator i = elems.iterator();
while (i.hasNext()) {
NameSpaceElement nse = (NameSpaceElement) i.next();
if (nse != null) {
String name = nse.getTypeRefName();
if ((name != null) && (name.indexOf(type) != -1)) {
r.add(nse);
}
name = nse.getTypeDefName();
if ((name != null) && (name.indexOf(type) != -1)) {
r.add(nse);
}
}
}
return r;
}
/**
* isValidDefinition purpose.
* <p>
* checks to see if the definition provided is found in the list of
* elements for this namespace.
* </p>
* @param definition The definition name to check for, may be either definition or prefix:definition.
* @return true when found, false otherwise.
*/
public boolean isValidDefinition(String definition) {
if ((definition == null) || (definition == "")) {
return false;
}
Set elems = getElements();
Iterator i = elems.iterator();
while (i.hasNext()) {
NameSpaceElement nse = (NameSpaceElement) i.next();
if (nse == null) {
continue;
}
String def = nse.getTypeDefName();
if ((def != null) && def.equals(definition)) {
return true;
}
def = nse.getQualifiedTypeDefName();
if ((def != null) && def.equals(definition)) {
return true;
}
}
return false;
}
/**
* isValidTypeRef purpose.
* <p>
* checks to see if the reference provided is found in the list of
* elements for this namespace.
* </p>
* @param definition The reference name to check for, may be either reference or prefix:reference.
* @return true when found, false otherwise.
*/
public boolean isValidTypeRef(String type) {
if ((type == null) || (type == "")) {
return false;
}
Set elems = getElements();
Iterator i = elems.iterator();
while (i.hasNext()) {
NameSpaceElement nse = (NameSpaceElement) i.next();
if (nse == null) {
continue;
}
String tp = nse.getTypeRefName();
if ((tp != null) && tp.equals(type)) {
return true;
}
tp = nse.getQualifiedTypeRefName();
if ((tp != null) && tp.equals(type)) {
return true;
}
}
return false;
}
/**
* getElements purpose.
* <p>
* returns the set of elements.
* </p>
* @return Set
*/
public abstract Set getElements();
/**
* getElements purpose.
* <p>
* Returns a set of all elements with the exact class specified.
* </p>
* @param type Class the class of elements to get
* @return Set
*/
public Set getElements(Class type) {
if (type == null) {
return null;
}
HashSet r = new HashSet();
Set elems = getElements();
Iterator i = elems.iterator();
while (i.hasNext()) {
NameSpaceElement nse = (NameSpaceElement) i.next();
if ((nse != null) && type.equals(nse.getJavaClass())) {
r.add(nse);
}
}
return r;
}
/**
* Gets an element definition by name.
*
* @param name The name of the element definition
* @return NameSpaceElement
*/
public NameSpaceElement getElement(String name) {
if (name == null) {
return null;
}
Set elems = getElements();
Iterator i = elems.iterator();
while (i.hasNext()) {
NameSpaceElement nse = (NameSpaceElement) i.next();
if (nse != null) {
if (name.equals(nse.getTypeRefName())) {
return nse;
}
if (name.equals(nse.getTypeDefName())) {
return nse;
}
if (name.equals(nse.getQualifiedTypeRefName())) {
return nse;
}
if (name.equals(nse.getQualifiedTypeDefName())) {
return nse;
}
}
}
return null;
}
/**
* Gets the default element for the class type passed in. Note that this
* is a bit hacky, as it doesn't not depend on a real namespace map, but
* on careful assignment of the NamespaceElements, so that each class only
* has one that returns true for isDefault(). Sorry for the hackiness,
* I need to get a release out.
*/
public NameSpaceElement getDefaultElement(Class type) {
Set posibilities = getElements(type);
//System.out.println("getting default for type: " + type + " = " + posibilities);
if (posibilities.size() == 0) {
return null;
}
Iterator i = posibilities.iterator();
while (i.hasNext()) {
NameSpaceElement nse = (NameSpaceElement) i.next();
if (nse != null) {
if (nse.isDefault()) {
return nse;
}
}
}
return null;
}
/**
* Gets an element definition by name.
*
* @param name The name of the element definition
* @return NameSpaceElement
*/
public NameSpaceElement getElement(Class type, String name) {
if (type == null) {
return null;
}
Set posibilities = getElements(type);
if (posibilities.size() == 0) {
return null;
}
if (posibilities.size() == 1) {
return (NameSpaceElement) posibilities.toArray()[0];
}
if (name == null) {
return (NameSpaceElement) posibilities.toArray()[0];
}
Iterator i = posibilities.iterator();
while (i.hasNext()) {
NameSpaceElement nse = (NameSpaceElement) i.next();
if (nse != null) {
if (name.equals(nse.getTypeRefName())) {
return nse;
}
if (name.equals(nse.getTypeDefName())) {
return nse;
}
if (name.equals(nse.getQualifiedTypeRefName())) {
return nse;
}
if (name.equals(nse.getQualifiedTypeDefName())) {
return nse;
}
if (nse.isDefault()) {
return nse;
}
}
}
return (NameSpaceElement) posibilities.toArray()[0];
}
/**
* getNameSpace purpose.
* <p>
* Returns the current namespace. Should be implemented as a constant.
* </p>
* @return String
*/
public abstract String getNameSpace();
/**
* getPrefix purpose.
* <p>
* Returns the prefix that this namespace represents.
* </p>
* @return String the prefix, null if it does not exist
*/
public final String getPrefix() {
return prefix;
}
}