com.ctc.wstx.sr.CompactNsContext Maven / Gradle / Ivy
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package com.ctc.wstx.sr;
import java.io.IOException;
import java.io.Writer;
import java.util.ArrayList;
import java.util.Iterator;
import javax.xml.XMLConstants;
import javax.xml.stream.Location;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamWriter;
import org.codehaus.stax2.ri.EmptyIterator;
import org.codehaus.stax2.ri.SingletonIterator;
// This is unfortunate dependency, but...
import org.codehaus.stax2.ri.evt.NamespaceEventImpl;
import com.ctc.wstx.util.BaseNsContext;
/**
* Simple implementation of separate non-transient namespace context
* object. Created for start-element event by transient namespace
* instance updated by stream reader.
*
* Note about implementation: Location information is only needed (and
* only needs to passed) if access is made via extended interface; one
* that can return information about actual Namespace event objects.
*/
public final class CompactNsContext
extends BaseNsContext
{
final Location mLocation;
/**
* Array that contains 2 Strings for each declared default namespace
* (including default namespace declarations); first is the prefix,
* second URI.
*/
final String[] mNamespaces;
/**
* Number of entries in {@link #mNamespaces} (which is twice the number
* of bindings)
*/
final int mNsLength;
/**
* Index of first namespace pair in mNamespaces that is declared
* in scope of element for which this context was constructed. May be
* equal to {@link #mNsLength} (which indicates there are no local
* bindings).
*/
final int mFirstLocalNs;
/**
* List only needed to support List accessor from start-element event;
* created lazily if/as needed.
*/
transient ArrayList mNsList;
public CompactNsContext(Location loc, String defaultNsURI,
String[] namespaces, int nsLen,
int firstLocal)
{
mLocation = loc;
mNamespaces = namespaces;
mNsLength = nsLen;
mFirstLocalNs = firstLocal;
}
/**
* @param prefix Non-null, non-empty prefix (base-class verifies these
* constraints) to find namespace URI for.
*/
public String doGetNamespaceURI(String prefix)
{
/* Let's search from beginning towards end; this way we'll first
* find the innermost (or, in case of same-level declaration, last)
* declaration for prefix.
*/
// (note: default namespace will be there too)
String[] ns = mNamespaces;
if (prefix.length() == 0) {
for (int i = mNsLength-2; i >= 0; i -= 2) {
if (ns[i] == null) {
return ns[i+1];
}
}
return null; // default ns not bound
}
for (int i = mNsLength-2; i >= 0; i -= 2) {
if (prefix.equals(ns[i])) {
return ns[i+1];
}
}
return null;
}
public String doGetPrefix(String nsURI)
{
// Note: base class checks for 'known' problems and prefixes:
String[] ns = mNamespaces;
int len = mNsLength;
main_loop:
for (int i = len-1; i > 0; i -= 2) {
if (nsURI.equals(ns[i])) {
/* 29-Sep-2004, TSa: Actually, need to make sure that this
* declaration is not masked by a later declaration.
* This happens when same prefix is declared on a later
* entry (ie. for child element)
*/
String prefix = ns[i-1];
for (int j = i+1; j < len; j += 2) {
// Prefixes are interned, can do straight equality check
if (ns[j] == prefix) {
continue main_loop; // was masked!
}
}
String uri = ns[i-1];
/* 19-Mar-2006, TSa: Empty namespaces are represented by
* null prefixes; but need to be represented as empty
* strings (to distinguish from unbound URIs).
*/
return (uri == null) ? "" : uri;
}
}
return null;
}
public Iterator doGetPrefixes(String nsURI)
{
// Note: base class checks for 'known' problems and prefixes:
String[] ns = mNamespaces;
int len = mNsLength;
String first = null;
ArrayList all = null;
main_loop:
for (int i = len-1; i > 0; i -= 2) {
String currNS = ns[i];
if (currNS == nsURI || currNS.equals(nsURI)) {
/* 29-Sep-2004, TSa: Need to ensure it's not masked by
* a later ns declaration in a child element.
*/
String prefix = ns[i-1];
for (int j = i+1; j < len; j += 2) {
// Prefixes are interned, can do straight equality check
if (ns[j] == prefix) {
continue main_loop; // was masked, need to ignore
}
}
/* 19-Mar-2006, TSa: Empty namespaces are represented by
* null prefixes; but need to be represented as empty
* strings (to distinguish from unbound URIs).
*/
if (prefix == null) {
prefix = "";
}
if (first == null) {
first = prefix;
} else {
if (all == null) {
all = new ArrayList();
all.add(first);
}
all.add(prefix);
}
}
}
if (all != null) {
return all.iterator();
}
if (first != null) {
return new SingletonIterator(first);
}
return EmptyIterator.getInstance();
}
/*
///////////////////////////////////////////////////////
// Extended API, needed by Wstx classes
///////////////////////////////////////////////////////
*/
public Iterator getNamespaces()
{
if (mNsList == null) {
int firstLocal = mFirstLocalNs;
int len = mNsLength - firstLocal;
if (len == 0) { // can this happen?
return EmptyIterator.getInstance();
}
if (len == 2) { // only one NS
return new SingletonIterator(NamespaceEventImpl.constructNamespace
(mLocation,
mNamespaces[firstLocal],
mNamespaces[firstLocal+1]));
}
ArrayList l = new ArrayList(len >> 1);
String[] ns = mNamespaces;
for (len = mNsLength; firstLocal < len;
firstLocal += 2) {
l.add(NamespaceEventImpl.constructNamespace(mLocation, ns[firstLocal],
ns[firstLocal+1]));
}
mNsList = l;
}
return mNsList.iterator();
}
/**
* Method called by {@link com.ctc.wstx.evt.CompactStartElement}
* to output all 'local' namespace declarations active in current
* namespace scope, if any. Local means that declaration was done in
* scope of current element, not in a parent element.
*/
public void outputNamespaceDeclarations(Writer w) throws IOException
{
String[] ns = mNamespaces;
for (int i = mFirstLocalNs, len = mNsLength; i < len; i += 2) {
w.write(' ');
w.write(XMLConstants.XMLNS_ATTRIBUTE);
String prefix = ns[i];
if (prefix != null && prefix.length() > 0) {
w.write(':');
w.write(prefix);
}
w.write("=\"");
w.write(ns[i+1]);
w.write('"');
}
}
public void outputNamespaceDeclarations(XMLStreamWriter w) throws XMLStreamException
{
String[] ns = mNamespaces;
for (int i = mFirstLocalNs, len = mNsLength; i < len; i += 2) {
String nsURI = ns[i+1];
String prefix = ns[i];
if (prefix != null && prefix.length() > 0) {
w.writeNamespace(prefix, nsURI);
} else {
w.writeDefaultNamespace(nsURI);
}
}
}
}