org.apache.woden.xpointer.XPointer Maven / Gradle / Ivy
/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.woden.xpointer;
import java.util.List;
import java.util.ArrayList;
import java.util.Map;
import java.util.HashMap;
import java.util.Iterator;
import java.lang.StringBuffer;
import org.apache.woden.types.NCName;
/**
* XPointer is a class which represents an XPointer defined in the XPointer Framework.
* This is specified at http://www.w3.org/TR/xptr-framework/
*
* @author Dan Harvey ([email protected])
*
*/
public class XPointer {
private static final String emptyString = "".intern();
private final Map prefixBindingContex;
private final Map namespaceBindingContex;
private NCName shorthandPointer;
private final List pointerParts;
private static final NCName emptyNCName = new NCName(emptyString);
private static final String NS_URI_XML = "http://www.w3.org/XML/1998/namespace";
private static final String NS_URI_XMLNS = "http://www.w3.org/2000/xmlns/";
private static final NCName NS_PREFIX_XMLNS = new NCName("xmlns");
/**
* Constructs a new XPointer.
*
*/
public XPointer() {
pointerParts = new ArrayList();
shorthandPointer = emptyNCName;
//Setup prefix/namespace binding context.
prefixBindingContex = new HashMap();
namespaceBindingContex = new HashMap();
addPrefixNamespaceBinding(new NCName("xml"), NS_URI_XML);
}
/**
* Constructs a new XPointer from the serialised string.
*
* @param xpointerString a String form of the XPointer to deserialise.
*/
public XPointer(String xpointerString) throws InvalidXPointerException {
this(); //Construct a new XPointer.
if (xpointerString == null || xpointerString.equals(emptyString))
throw new InvalidXPointerException("The XPointer string is either null or empty", emptyString);
XPointerParser.parseXPointer(xpointerString, this); //Parse the string and add the Pointers to the new XPointer.
}
/**
* Appends a pointer part to the end of this XPointer.
*
* @param pointerPart the Pointer Part to append.
* @throws UnsupportedOperationException() if a Shorthand Pointer is already set.
*/
public void addPointerPart(PointerPart pointerPart) {
if(!shorthandPointer.equals(emptyNCName)) {
throw new UnsupportedOperationException("A Shortname Pointer already exists for this XPointer.");
} else {
pointerParts.add(pointerPart);
}
}
/**
* Inserts a pointer part at index of this XPointer.
*
* @param pointerPart the Pointer Part to inserted.
* @param index an integer specifying the point to insert the pointer part.
* @throws UnsupportedOperationException() if a Shorthand Pointer is already set.
*/
public void addPointerPart(int index, PointerPart pointerPart) {
if(hasShorthandPointer()) {
throw new UnsupportedOperationException("A Shortname Pointer already exists for this XPointer.");
}
if(index < 0 || index > pointerParts.size()) {
throw new IndexOutOfBoundsException("The index you gave is out of the bounds of the list of XPointers");
}
pointerParts.add(index, pointerPart);
}
/**
* Returns the pointer parts in this XPointer.
*
* @return a PointerPart[] of type Object[] containing the pointer parts in this XPointer.
* @throws IllegalStateException if this XPointer has a shorthand pointer.
*/
public Object[] getPointerParts() {
if (hasPointerParts()) {
int size = pointerParts.size();
Object[] parts = new Object[size]; //Ugly but it will have to do for Java 1.4
for(int i=0; ihttp://www.w3.org/TR/xptr-framework/#nsContext
*/
public void addPrefixNamespaceBinding(NCName prefix, String namespace) {
if (prefix == null)
throw new NullPointerException("The prefix argument provided has a null pointer.");
if (namespace == null)
throw new NullPointerException("The namespace argument provided has a null pointer.");
if (prefix.equals(NS_PREFIX_XMLNS))
throw new IllegalArgumentException("The xmlns prefix must not be bound to any namespace.");
if (namespace.equals(NS_URI_XMLNS))
throw new IllegalArgumentException("The " + NS_URI_XMLNS + " namespace must not be bound to any prefix.");
//Its a valid binding so add it to the binding contex.
prefixBindingContex.put(prefix, namespace);
namespaceBindingContex.put(namespace, prefix);
}
/**
* Gets the Namespace the Prefix is bound to if the binding exists,
* otherwise it will return null.
*
* @param prefix a NCName of the prefix bound to the namespace.
* @return A String of the namespace bound to this prefix or null if none exists.
*/
public String getPrefixBinding(NCName prefix) {
return (String)prefixBindingContex.get(prefix);
}
/**
* Gets Prefix the Namespace is bound to if the binding exists,
* otherwise it will return null.
*
* @param namespace a String of the prefix bound to the prefix.
* @return A NCName of the prefix bound to this namespace or null if none exists.
*/
public NCName getNamespaceBinding(String namespace) {
return (NCName)namespaceBindingContex.get(namespace);
}
/**
* Checks whether a prefix is bound or not.
*
* @param prefix A NCName of the prefix to check.
* @return a boolean value that is true if the binding exists, or false otherwise.
*/
public boolean hasPrefixBinding(NCName prefix) {
return prefixBindingContex.containsKey(prefix);
}
/**
* Checks whether a namespace is bound or not.
*
* @param namespace A String of the namespace to check.
* @return a boolean value that is true if the binding exists, or false otherwise.
*/
public boolean hasNamespaceBinding(String namespace) {
return namespaceBindingContex.containsKey(namespace);
}
/**
* Tests whether this XPointer has a shorthand pointer or not.
*
* @return a boolean which is true if this XPointer contains an shorthand pointer, false otherwise.
*/
public boolean hasShorthandPointer() {
return !shorthandPointer.equals(emptyNCName);
}
/**
* Tests whether this XPointer has scheme based pointers or not.
*
* @return a boolean which is true if this XPointer contains scheme based pointers, false otherwise.
*/
public boolean hasPointerParts() {
return !pointerParts.isEmpty();
}
/**
* Returns a String serialisation of this XPointer.
*
* @return a String containing the serialisation of this XPointer
*/
public String toString() {
if (shorthandPointer.equals(emptyNCName)) {
StringBuffer buffer = new StringBuffer();
Iterator parts = pointerParts.iterator();
while (parts.hasNext()) {
buffer.append(parts.next());
}
return buffer.toString();
} else {
return shorthandPointer.toString();
}
}
}