/*
* 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.xerces.impl.scd;
import java.util.ArrayList;
import java.util.List;
import org.apache.xerces.util.NamespaceSupport;
import org.apache.xerces.xni.NamespaceContext;
import org.apache.xerces.xni.QName;
import org.apache.xerces.util.XML11Char;
//import org.apache.xml.serializer.utils.XML11Char;
/**
* This class handles the parsing of relative/incomplete SCDs/SCPs
* @author Ishan Jayawardena udeshike@gmail.com
* @version $Id: SCDParser.java 1023886 2010-10-18 16:23:20Z sandygao $
*/
class SCDParser {
private List steps;
private static final int CHARTYPE_AT = 1; // @
private static final int CHARTYPE_TILDE = 2; // ~
private static final int CHARTYPE_PERIOD = 3; // .
private static final int CHARTYPE_STAR = 4; // *
private static final int CHARTYPE_ZERO = 5; // 0
private static final int CHARTYPE_1_THROUGH_9 = 6; // [1-9]
private static final int CHARTYPE_NC_NAMESTART = 7; // XML11Char.NCNameStart
private static final int CHARTYPE_NC_NAME = 8; // XML11Char.NCName
private static final int CHARTYPE_OPEN_BRACKET = 9; // [
private static final int CHARTYPE_CLOSE_BRACKET = 10;// ]
private static final int CHARTYPE_OPEN_PAREN = 11; // (
private static final int CHARTYPE_CLOSE_PAREN = 12; // )
private static final int CHARTYPE_COLON = 13; // :
private static final int CHARTYPE_SLASH = 14; // /
private static final int CHARTYPE_NOMORE = 0;
private static final short LIST_SIZE = 15;
public SCDParser() {
steps = new ArrayList(LIST_SIZE);
}
private static int getCharType(int c) throws SCDException {
switch (c) {
case '@':
return CHARTYPE_AT;
case '~':
return CHARTYPE_TILDE;
case '.':
return CHARTYPE_PERIOD;
case '*':
return CHARTYPE_STAR;
case ':':
return CHARTYPE_COLON;
case '/':
return CHARTYPE_SLASH;
case '(':
return CHARTYPE_OPEN_PAREN;
case ')':
return CHARTYPE_CLOSE_PAREN;
case '[':
return CHARTYPE_OPEN_BRACKET;
case ']':
return CHARTYPE_CLOSE_BRACKET;
case '0':
return CHARTYPE_ZERO;
}
if (c == CHARTYPE_NOMORE) {
return CHARTYPE_NOMORE;
}
if (c >= '1' && c <= '9') {
return CHARTYPE_1_THROUGH_9;
}
if (XML11Char.isXML11NCNameStart(c)) {
return CHARTYPE_NC_NAMESTART;
}
if (XML11Char.isXML11NCName(c)) {
return CHARTYPE_NC_NAME;
}
throw new SCDException("Error in SCP: Unsupported character "
+ (char) c + " (" + c + ")");
}
public static char charAt(String s, int position) {
if (position >= s.length()) {
return (char) -1; // TODO: throw and exception instead?
//throw new SCDException("Error in SCP: No more characters in the SCP string");
}
return s.charAt(position);
}
private static QName readQName(String step, int[] finalPosition, int currentPosition, NamespaceContext nsContext)
throws SCDException {
return readNameTest(step, finalPosition, currentPosition, nsContext);
}
/**
* TODO: this is the wild card name test
*/
public static final QName WILDCARD = new QName(null, "*", "*", null);
/**
* TODO: this is the name test zero
*/
public static final QName ZERO = new QName(null, "0", "0", null);
/*
* Similar to readQName() method. But this method additionally tests for another two types
* of name tests. i.e the wildcard name test and the zero name test.
*/
private static QName readNameTest(String step, int[] finalPosition, int currentPosition, NamespaceContext nsContext)
throws SCDException {
int initialPosition = currentPosition;
int start = currentPosition;
String prefix = ""; // for the default namespace
String localPart = null;
if (charAt(step, currentPosition) == '*') {
finalPosition[0] = currentPosition + 1;
return WILDCARD;
} else if (charAt(step, currentPosition) == '0') {
finalPosition[0] = currentPosition + 1;
return ZERO;
// prefix, localPart, rawname, uri;
} else if (XML11Char.isXML11NCNameStart(charAt(step, currentPosition))) {
while (XML11Char.isXML11NCName(charAt(step, ++currentPosition))) {}
prefix = step.substring(initialPosition, currentPosition);
if (charAt(step, currentPosition) == ':') {
if (XML11Char
.isXML11NCNameStart(charAt(step, ++currentPosition))) {
initialPosition = currentPosition;
while (XML11Char.isXML11NCName(charAt(step,
currentPosition++))) {
}
localPart = step.substring(initialPosition,
currentPosition - 1);
}
if (localPart == null) {
localPart = prefix;
prefix = "";
}
finalPosition[0] = currentPosition - 1;
} else {
finalPosition[0] = currentPosition;
localPart = prefix;
prefix = "";
}
String rawname = step.substring(start, finalPosition[0]);
if (nsContext != null) {
// it a field
String uri = nsContext.getURI(prefix.intern());
if ("".equals(prefix)) { // default namespace.
return new QName(prefix, localPart, rawname, uri);
} else if (uri != null) {
// just use uri != null test here!
return new QName(prefix, localPart, rawname, uri);
}
throw new SCDException("Error in SCP: The prefix \"" + prefix
+ "\" is undeclared in this context");
}
throw new SCDException("Error in SCP: Namespace context is null");
}
throw new SCDException("Error in SCP: Invalid nametest starting character \'"
+ charAt(step, currentPosition) + "\'");
} // readNameTest()
private static int scanNCName(String data, int currentPosition) {
if (XML11Char.isXML11NCNameStart(charAt(data, currentPosition))) {
while (XML11Char.isXML11NCName(charAt(data, ++currentPosition))) {
}
}
return currentPosition;
}
/* scans a XML namespace Scheme Data section
* [2] EscapedNamespaceName ::= EscapedData*
* [6] SchemeData ::= EscapedData*
* [7] EscapedData ::= NormalChar | '^(' | '^)' | '^^' | '(' SchemeData ')'
* [8] NormalChar ::= UnicodeChar - [()^]
* [9] UnicodeChar ::= [#x0-#x10FFFF]
*/
private static int scanXmlnsSchemeData(String data, int currentPosition) throws SCDException {
int c = 0;
int balanceParen = 0;
do {
c = charAt(data, currentPosition);
if (c >= 0x0 && c <= 0x10FFFF) { // unicode char
if (c != '^') { // normal char
++currentPosition;
if (c == '(') {
++balanceParen;
} else if (c == ')') { // can`t be empty '(' xmlnsSchemeData ')'
--balanceParen;
if (balanceParen == -1) {
// this is the end
return currentPosition - 1;
}
if (charAt(data, currentPosition - 2) == '(') {
throw new SCDException(
"Error in SCD: empty xmlns scheme data between '(' and ')'");
}
}
} else { // check if '^' is used as an escape char
if (charAt(data, currentPosition + 1) == '('
|| charAt(data, currentPosition + 1) == ')'
|| charAt(data, currentPosition + 1) == '^') {
currentPosition = currentPosition + 2;
} else {
throw new SCDException("Error in SCD: \'^\' character is used as a non escape character at position "
+ ++currentPosition);
}
}
} else {
throw new SCDException("Error in SCD: the character \'" + c + "\' at position "
+ ++currentPosition + " is invalid for xmlns scheme data");
}
} while (currentPosition < data.length());
String s = "";
if (balanceParen != -1) { // checks unbalanced l parens only.
s = "Unbalanced parentheses exist within xmlns scheme data section";
}
throw new SCDException("Error in SCD: Attempt to read an invalid xmlns Scheme data. " + s);
}
private static int skipWhiteSpaces(String data, int currentPosition) {
while (XML11Char.isXML11Space(charAt(data, currentPosition))) {
++currentPosition; // this is important
}
return currentPosition;
}
// Scans a predicate from the input string step
private static int readPredicate(String step, int[] finalPosition,
int currentPosition) throws SCDException {
// we've already seen a '['
int end = step.indexOf(']', currentPosition);
if (end >= 0) {
try {
int i = Integer.parseInt(step.substring(currentPosition, end)); // toString?
if (i > 0) {
finalPosition[0] = end + 1;
return i;
}
throw new SCDException("Error in SCP: Invalid predicate value "
+ i);
} catch (NumberFormatException e) {
e.printStackTrace();
throw new SCDException(
"Error in SCP: A NumberFormatException occurred while reading the predicate");
}
}
throw new SCDException(
"Error in SCP: Attempt to read an invalid predicate starting from position "
+ ++currentPosition);
} // readPredicate()
/**
* Processes the scp input string and seperates it into Steps
* @param scp the input string that contains an SCDParser
* @return a list of Steps contained in the SCDParser
*/
public List parseSCP(String scp, NamespaceContext nsContext, boolean isRelative)
throws SCDException {
steps.clear();
Step step;
if (scp.length() == 1 && scp.charAt(0) == '/') { // read a schema
// schema step.
//System.out.println("<SCHEMA STEP>");
steps.add(new Step(Axis.NO_AXIS, null, 0));
return steps;
}
// check if this is an incomplete SCP
if (isRelative) {
if ("./".equals(scp.substring(0, 2))) {
scp = scp.substring(1);
} else if (scp.charAt(0) != '/') {
scp = '/' + scp;
} else {
throw new SCDException("Error in incomplete SCP: Invalid starting character");
}
}
int stepStart = 0;
int[] currentPosition = new int[] { 0 };
while (currentPosition[0] < scp.length()) {
if (charAt(scp, currentPosition[0]) == '/') {
if (charAt(scp, currentPosition[0] + 1) == '/') {
if (currentPosition[0] + 1 != scp.length() - 1) {
steps.add(new Step(Axis.SPECIAL_COMPONENT, WILDCARD, 0));
stepStart = currentPosition[0] + 2;
} else {
stepStart = currentPosition[0] + 1;
}
} else {
if (currentPosition[0] != scp.length() - 1) {
stepStart = currentPosition[0] + 1;
} else {
stepStart = currentPosition[0];
}
}
step = processStep(scp, currentPosition, stepStart, nsContext);
steps.add(step);
} else { // error: invalid scp. should start with a slash
throw new SCDException("Error in SCP: Invalid character \'"
+ charAt(scp, currentPosition[0]) + " \' at position"
+ currentPosition[0]);
}
}
return steps;
}
private static Step processStep(String step, int[] newPosition, int currentPosition, NamespaceContext nsContext)
throws SCDException {
short axis = -1;
QName nameTest = null;
int predicate = 0;
switch (getCharType(charAt(step, currentPosition))) { // 0
case CHARTYPE_AT: // '@'
axis = Axis.SCHEMA_ATTRIBUTE;
nameTest = readNameTest(step, newPosition, currentPosition + 1,
nsContext); // 1 handles *, 0, and QNames.
break;
case CHARTYPE_TILDE: // '~'
axis = Axis.TYPE;
nameTest = readNameTest(step, newPosition, currentPosition + 1,
nsContext); // 1
break;
case CHARTYPE_PERIOD: // '.'
axis = Axis.CURRENT_COMPONENT;
nameTest = WILDCARD;
newPosition[0] = currentPosition + 1;
break;
case CHARTYPE_ZERO: // '0'
axis = Axis.SCHEMA_ELEMENT; // Element without a name. This will
// never match anything.
nameTest = ZERO;
newPosition[0] = currentPosition + 1;
break;
case CHARTYPE_STAR: // '*'
axis = Axis.SCHEMA_ELEMENT;
nameTest = WILDCARD;
newPosition[0] = currentPosition + 1;
break;
case CHARTYPE_NC_NAMESTART: // isXML11NCNameStart()
QName name = readQName(step, newPosition, currentPosition,
nsContext); // 0 handles a and a:b
int newPos = newPosition[0];
if (newPosition[0] == step.length()) {
axis = Axis.SCHEMA_ELEMENT;
nameTest = name;
} else if (charAt(step, newPos) == ':'
&& charAt(step, newPos + 1) == ':') {
// TODO: what to do with extension axes?
// Could be a hashtable look up; fail if extension axis
axis = Axis.qnameToAxis(name.rawname);
if (axis == Axis.EXTENSION_AXIS) {
throw new SCDException(
"Error in SCP: Extension axis {"+name.rawname+"} not supported!");
}
nameTest = readNameTest(step, newPosition, newPos + 2,
nsContext);
} else if (charAt(step, newPos) == '(') {
throw new SCDException(
"Error in SCP: Extension accessor not supported!");
} else if (charAt(step, newPos) == '/') { // /abc:def/...
axis = Axis.SCHEMA_ELEMENT;
nameTest = name;
return new Step(axis, nameTest, predicate);
} else { // /abc:def[6]
axis = Axis.SCHEMA_ELEMENT;
nameTest = name;
}
break;
default:
throw new SCDException("Error in SCP: Invalid character \'"
+ charAt(step, currentPosition) + "\' at position "
+ currentPosition);
}
if (newPosition[0] < step.length()) {
if (charAt(step, newPosition[0]) == '[') {
predicate = readPredicate(step, newPosition, newPosition[0] + 1); // Also consumes right-bracket
} else if (charAt(step, newPosition[0]) == '/') { // /a::a/a...
return new Step(axis, nameTest, predicate);
} else {
throw new SCDException("Error in SCP: Unexpected character \'"
+ charAt(step, newPosition[0]) + "\' at position "
+ newPosition[0]);
}
// TODO: handle what if not?
}
if (charAt(step, newPosition[0]) == '/') {// /abc:def[6]/...
return new Step(axis, nameTest, predicate);
}
if (newPosition[0] < step.length()) {
throw new SCDException("Error in SCP: Unexpected character \'"
+ step.charAt(newPosition[0]) + "\' at the end");
}
return new Step(axis, nameTest, predicate);
} // processStep()
/**
* Creates a list of Step objects from the input relative SCD string by
* parsing it
* @param relativeSCD
* @param isIncompleteSCD if the relative SCD in the first parameter an incomplete SCD
* @return the list of Step objects
*/
public List parseRelativeSCD(String relativeSCD, boolean isIncompleteSCD) throws SCDException {
// xmlns(p=http://example.com/schema/po)xscd(/type::p:USAddress)
int[] currentPosition = new int[] { 0 };
NamespaceContext nsContext = new NamespaceSupport();
//System.out.println("Relative SCD## " + relativeSCD);
while (currentPosition[0] < relativeSCD.length()) {
if ("xmlns".equals(relativeSCD.substring(currentPosition[0], currentPosition[0] + 5))) { // TODO catch string out of bound exception
currentPosition[0] = readxmlns(relativeSCD, nsContext, currentPosition[0] + 5);
} else if ("xscd".equals(relativeSCD.substring(currentPosition[0], currentPosition[0] + 4))) { // (/type::p:USAddress) part
// process xscd() part
String data = relativeSCD.substring(currentPosition[0] + 4, relativeSCD.length());
if (charAt(data, 0) == '('
&& charAt(data, data.length() - 1) == ')') {
return parseSCP(data.substring(1, data.length() - 1), nsContext, isIncompleteSCD);
}
throw new SCDException("Error in SCD: xscd() part is invalid at position "
+ ++currentPosition[0]);
} else {
throw new SCDException("Error in SCD: Expected \'xmlns\' or \'xscd\' at position "
+ ++currentPosition[0]);
}
}
throw new SCDException("Error in SCD: Error at position "
+ ++currentPosition[0]);
} // createSteps()
private static int readxmlns(String data, NamespaceContext nsContext,
int currentPosition) throws SCDException {
if (charAt(data, currentPosition++) == '(') {
// readNCName
int pos = currentPosition;
currentPosition = scanNCName(data, currentPosition);
if (currentPosition == pos) {
throw new SCDException(
"Error in SCD: Missing namespace name at position "
+ ++currentPosition);
}
String name = data.substring(pos, currentPosition);
// skip S
currentPosition = skipWhiteSpaces(data, currentPosition);
// read '='
if (charAt(data, currentPosition) != '=') {
throw new SCDException("Error in SCD: Expected a \'=\' character at position "
+ ++currentPosition);
}
// skip S
currentPosition = skipWhiteSpaces(data, ++currentPosition);
// read uri
pos = currentPosition;
currentPosition = scanXmlnsSchemeData(data, currentPosition);
if (currentPosition == pos) {
throw new SCDException("Error in SCD: Missing namespace value at position "
+ ++currentPosition);
}
String uri = data.substring(pos, currentPosition);
if (charAt(data, currentPosition) == ')') {
nsContext.declarePrefix(name.intern(), uri.intern());
return ++currentPosition;
}
throw new SCDException("Error in SCD: Invalid xmlns pointer part at position "
+ ++currentPosition);
}
throw new SCDException("Error in SCD: Invalid xmlns pointer part at position "
+ ++currentPosition);
} // readxmlns()
}