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A library for core classes (Graph, Vertex, Edge, etc.)
package io.konig.rio.turtle;
/*
* #%L
* Konig Core
* %%
* Copyright (C) 2015 - 2017 Gregory McFall
* %%
* Licensed 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.
* #L%
*/
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PushbackReader;
import java.io.Reader;
import java.io.StringReader;
import org.openrdf.model.BNode;
import org.openrdf.model.Literal;
import org.openrdf.model.Resource;
import org.openrdf.model.Statement;
import org.openrdf.model.URI;
import org.openrdf.model.Value;
import org.openrdf.model.ValueFactory;
import org.openrdf.model.vocabulary.RDF;
import org.openrdf.model.vocabulary.XMLSchema;
import org.openrdf.rio.RDFFormat;
import org.openrdf.rio.RDFHandlerException;
import org.openrdf.rio.RDFParseException;
import org.openrdf.rio.helpers.RDFParserBase;
import io.konig.core.util.IriTemplate;
public class TurtleParser extends RDFParserBase {
private static final int PUSH_BACK_SIZE = 20;
protected PushbackReader reader;
protected StringBuilder buffer = new StringBuilder();
private String baseURI;
private int lineNumber=1;
private int columnNumber;
protected NamespaceMap namespaceMap;
public TurtleParser() {
namespaceMap = new HashNamespaceMap();
}
public TurtleParser(NamespaceMap namespaceMap) {
this.namespaceMap = namespaceMap==null ? new HashNamespaceMap() : namespaceMap;
}
public TurtleParser(NamespaceMap namespaceMap, ValueFactory valueFactory) {
super(valueFactory);
this.namespaceMap = namespaceMap;
}
protected StringBuilder buffer() {
buffer.setLength(0);
return buffer;
}
protected String nextWord(String delim) throws IOException {
skipSpace();
StringBuilder buffer = buffer();
int c;
while ((c = read()) != -1) {
if (delim.lastIndexOf(c) >= 0) {
unread(c);
break;
}
buffer.appendCodePoint(c);
}
return buffer.toString();
}
public NamespaceMap getNamespaceMap() {
return namespaceMap;
}
private void turtleDoc() throws IOException, RDFParseException, RDFHandlerException {
lineNumber = 1;
columnNumber = 0;
if (rdfHandler != null) {
rdfHandler.startRDF();
}
int c = 0;
while (c != -1) {
statement();
c = next();
unread(c);
}
if (rdfHandler!= null) {
rdfHandler.endRDF();
}
}
private void statement() throws IOException, RDFParseException, RDFHandlerException {
int c = next();
if (c == '@') {
directive(c);
} else {
triples(c);
read('.');
}
}
protected void directive(int c) throws IOException, RDFParseException, RDFHandlerException {
if (tryWord("prefix")) {
prefixID();
} else if (tryWord("base")) {
base();
}
}
protected void base() throws RDFParseException {
fail("@base directive is not supported");
// TODO: implement @base directive
}
/**
*
* prefixID ::= '@prefix' PNAME_NS IRIREF '.'
*
* This method assumes we have already read '@prefix'
*/
protected void prefixID() throws RDFParseException, IOException, RDFHandlerException {
readSpace();
String prefix = pname_ns();
String iriRef = iriRef(next());
read('.');
namespaceMap.put(prefix, iriRef);
namespace(prefix, iriRef);
}
protected void namespace(String prefix, String name) throws RDFHandlerException {
if (rdfHandler!=null) {
rdfHandler.handleNamespace(prefix, name);
}
}
/**
*
* PNAME_NS ::= PN_PREFIX? ':'
*
*/
protected String pname_ns() throws IOException, RDFParseException {
StringBuilder builder = buffer();
int c = next();
pn_prefix(c);
c = next();
if (c != ':') {
builder = err();
builder.append("Expected ':' but found '");
appendCodePoint(builder, c);
builder.append("'");
fail(builder);
}
return builder.toString();
}
protected String pn_prefix() throws RDFParseException, IOException {
buffer();
int c = next();
pn_prefix(c);
return buffer.toString();
}
/**
* PN_PREFIX ::= PN_CHARS_BASE ((PN_CHARS | '.')* PN_CHARS)?
*/
protected void pn_prefix(int c) throws IOException, RDFParseException {
if (pn_chars_base(c)) {
buffer.appendCodePoint(c);
boolean endsWithDot=false;
for (;;) {
c = read();
if (pn_chars(c)) {
buffer.appendCodePoint(c);
endsWithDot = false;
} else if (c=='.') {
buffer.appendCodePoint(c);
endsWithDot = true;
} else {
break;
}
}
if (endsWithDot) {
throw new RDFParseException("Namespace prefix cannot end with '.'");
}
}
unread(c);
}
/**
* PN_CHARS ::= PN_CHARS_U | '-' | [0-9] | #x00B7 | [#x0300-#x036F] | [#x203F-#x2040]
*/
protected boolean pn_chars(int c) {
return
pn_chars_u(c) ||
(c == '-') ||
inRange(c, '0', '9') ||
(c == 0xB7) ||
inRange(c, 0x300, 0x36F) ||
inRange(c, 0x203F, 0x2040);
}
/**
* PN_CHARS_U ::= PN_CHARS_BASE | '_'
*/
protected boolean pn_chars_u(int c) {
return
pn_chars_base(c) ||
(c == '_') ;
}
protected boolean pn_chars_base(int c) {
return
inRange(c, 'A', 'Z') ||
inRange(c, 'a', 'z') ||
inRange(c, 0xC0, 0xD6) ||
inRange(c, 0xD8, 0xF6) ||
inRange(c, 0xF8, 0x2FF) ||
inRange(c, 0x370, 0x37D) ||
inRange(c, 0x37F, 0x1FFF) ||
inRange(c, 0x200C, 0x200D) ||
inRange(c, 0x2070, 0x218F) ||
inRange(c, 0x2C00, 0x2FEF) ||
inRange(c, 0x3001, 0xD7FF) ||
inRange(c, 0xF900, 0xFDCF) ||
inRange(c, 0xFDF0, 0xFFFD) ||
inRange(c, 0x10000, 0xEFFFF)
;
}
protected boolean inRange(int c, int min, int max) {
return c>=min && c<=max;
}
protected void readSpace() throws IOException, RDFParseException {
int c = read();
if (!isWhitespace(c)) {
StringBuilder err = err();
err.append("Expected whitespace but found '");
appendCodePoint(err, c);
err.append("'");
fail(err);
}
skipSpace();
}
protected boolean skipSpace() throws IOException {
boolean result = false;
int c = read();
while (isWhitespace(c)) {
result = true;
c = read();
}
unread(c);
return result;
}
protected void triples(int c) throws RDFParseException, IOException, RDFHandlerException {
boolean done = false;
if (c == '[') {
BNode subject = tryBlankNodePropertyList(c);
if (subject != null) {
done = true;
c = next();
unread(c);
if (c != '.') {
predicateObjectList(subject);
}
}
}
if (!done) {
Resource subject = subject(c);
predicateObjectList(subject);
}
}
protected void predicateObjectList(Resource subject) throws IOException, RDFParseException, RDFHandlerException {
URI predicate = verb();
objectList(subject, predicate);
int c = next();
while (c == ';') {
predicate = verb();
objectList(subject, predicate);
c = next();
}
unread(c);
}
private void objectList(Resource subject, URI predicate) throws IOException, RDFHandlerException, RDFParseException {
int c = next();
Value object = object(c);
statement(subject, predicate, object);
c = next();
while (c == ',') {
c = next();
object = object(c);
statement(subject, predicate, object);
c = next();
}
unread(c);
}
protected void statement(Resource subject, URI predicate, Value object) throws RDFHandlerException {
if (rdfHandler != null) {
Statement st = valueFactory.createStatement(subject, predicate, object);
rdfHandler.handleStatement(st);
}
}
/**
*
* object ::= iri | BlankNode | collection | blankNodePropertyList | literal
*
*/
protected Value object(int c) throws RDFParseException, IOException, RDFHandlerException {
Value value = null;
value =
(value=tryCollection(c)) != null ? value :
(value=tryLiteral(c)) != null ? value :
(value=tryBlankNode(c)) != null ? value :
(value=tryBlankNodePropertyList(c)) != null ? value :
(value=tryIri(c)) != null ? value :
null;
if (value == null) {
fail("Expected (iri | BlankNode | collection | blankNodePropertyList | literal)");
}
return value;
}
private Value tryCollection(int c) {
// TODO Auto-generated method stub
return null;
}
protected BNode blankNodePropertyList() throws IOException, RDFParseException, RDFHandlerException {
int c = read();
BNode result = tryBlankNodePropertyList(c);
if (result == null) {
unread(c);
}
return result;
}
/**
*
* blankNodePropertyList ::= '[' predicateObjectList ']'
*
* @throws IOException
* @throws RDFHandlerException
* @throws RDFParseException
*/
protected BNode tryBlankNodePropertyList(int c) throws IOException, RDFParseException, RDFHandlerException {
if (c != '[') {
return null;
}
c = next();
unread(c);
if (c == ']') {
// No properties inside this BNode.
return null;
}
BNode bnode = valueFactory.createBNode();
predicateObjectList(bnode);
c = next();
if (c != ']') {
StringBuilder builder = err();
builder.append("Expected ']' but found '");
appendCodePoint(builder, c);
builder.append("'");
fail(builder);
}
return bnode;
}
protected void appendCodePoint(StringBuilder builder, int c) {
if (c == -1) {
builder.append("<>");
} else {
builder.appendCodePoint(c);
}
}
protected Literal tryLiteral() throws IOException, RDFParseException, RDFHandlerException {
int c = read();
Literal literal = tryLiteral(c);
if (literal == null) {
unread(c);
}
return literal;
}
/**
*
* literal ::= RDFLiteral | NumericLiteral | BooleanLiteral
*
* @throws IOException
* @throws RDFParseException
* @throws RDFHandlerException
*/
private Literal tryLiteral(int c) throws IOException, RDFParseException, RDFHandlerException {
Literal value = null;
value =
(value=tryRDFLiteral(c)) != null ? value :
(value=tryNumericLiteral(c)) != null ? value :
(value=tryBooleanLiteral(c)) != null ? value :
null;
return value;
}
private Literal tryBooleanLiteral(int c) throws IOException {
Literal result = null;
if ((c=='t') && tryWord("rue")) {
result = valueFactory.createLiteral(true);
} else if ((c=='f') && tryWord("alse")) {
result = valueFactory.createLiteral(false);
}
if (result != null) {
c = read();
unread(c);
if (!isWhitespace(c) && (c != ',') && (c!=';') && (c!='.') && (c!='/') && (c!='^') && (c!=']')) {
boolean value = result.booleanValue();
if (value) {
unread("rue");
} else {
unread("alse");
}
result = null;
}
}
return result;
}
protected void unread(String text) throws IOException {
for (int i=text.length()-1; i>=0; i--) {
unread(text.charAt(i));
}
}
/**
*
* NumericLiteral ::= INTEGER | DECIMAL | DOUBLE
*
* INTEGER ::= [+-]? [0-9]+
*
* DECIMAL ::= [+-]? [0-9]* '.' [0-9]+
*
* DOUBLE ::= [+-]? ([0-9]+ '.' [0-9]* EXPONENT | '.' [0-9]+ EXPONENT | [0-9]+ EXPONENT)
*
*
*
*
* We have the following possible parses
*
*
* [+-]?
* [0-9]+ >>>> INTEGER
* '.' [0-9]+ >>>> DECIMAL
* '.' [0-9]+ EXPONENT >>>> DOUBLE
* '.' EXPONENT >>>> DOUBLE
* EXPONENT >>>> DOUBLE
* '.' [0-9]+ >>>> DECIMAL
* '.' [0-9]+ EXPONENT >>>> DOUBLE
*
*
*
* Let's define the following production rules.
*
*
*
* NumericLiteral ::= UnsignedNumber | [+-] UnsignedNumber
*
* UnsignedNumber ::= NumberWithIntegerPart | DecimalPart ;
*
* NumberWithIntegerPart ::= [0-9]+ (DecimalPart | EXPONENT)?
*
* DecimalPart ::= '.' [0-9]+ EXPONENT?
*
*
*/
private Literal tryNumericLiteral(int c) throws IOException, RDFParseException {
Literal result = null;
boolean digit = isDigit(c);
if (
!digit &&
c!='+' &&
c!='-' &&
c!= '.'
) {
return null;
}
StringBuilder builder = buffer();
if (c=='+' || c=='-') {
builder.appendCodePoint(c);
c = read();
digit = isDigit(c);
}
if (digit) {
result = numberWithIntegerPart(c);
} else if (c=='.') {
result = tryDecimalPart(c);
} else {
builder = err();
builder.append("Invalid numeric literal. Expected [0-9] or '.' but found '");
builder.appendCodePoint(c);
builder.append("'");
fail(builder);
}
return result;
}
/**
*
* DecimalPart ::= '.' [0-9]+ EXPONENT?
*
* @throws IOException
* @throws RDFParseException
*/
private Literal tryDecimalPart(int c) throws IOException, RDFParseException {
Literal result = null;
if (c=='.') {
c = read();
if (c=='e' | c=='E') {
buffer.append('.');
result = tryExponent(c);
} else if (!isDigit(c)) {
// Do nothing
} else {
buffer.append('.');
while (isDigit(c)) {
buffer.appendCodePoint(c);
c = read();
}
result = tryExponent(c);
if (result == null) {
unread(c);
result = valueFactory.createLiteral(buffer.toString(), XMLSchema.DECIMAL);
}
}
if (result == null) {
unread(c);
}
}
return result;
}
/**
*
* NumberWithIntegerPart ::= [0-9]+ (DecimalPart | EXPONENT)?
*
* @return
* @throws IOException
* @throws RDFParseException
*/
private Literal numberWithIntegerPart(int c) throws RDFParseException, IOException {
while (isDigit(c)) {
buffer.appendCodePoint(c);
c = read();
}
Literal result =
(result=tryDecimalPart(c)) != null ? result :
(result=tryExponent(c)) != null ? result :
integerLiteral(c);
return result;
}
private Literal integerLiteral(int c) throws IOException {
unread(c);
return valueFactory.createLiteral(buffer.toString(), XMLSchema.INTEGER);
}
/**
*
* EXPONENT ::= [eE] [+-]? [0-9]+
*
* @throws IOException
* @throws RDFParseException
*/
private Literal tryExponent(int c) throws IOException, RDFParseException {
Literal result = null;
if (c == 'e' || c=='E') {
buffer.appendCodePoint(c);
c = read();
if (c=='+' || c=='-') {
buffer.appendCodePoint(c);
c = read();
}
if (!isDigit(c)) {
unread(c);
return null;
}
while (isDigit(c)) {
buffer.appendCodePoint(c);
c = read();
}
unread(c);
result = valueFactory.createLiteral(buffer.toString(), XMLSchema.DOUBLE);
}
return result;
}
protected boolean isLetter(int c) {
return inRange(c, 'a', 'z') || inRange(c, 'A', 'Z');
}
protected boolean isDigit(int c) {
return c>='0' && c<='9';
}
/**
*
* RDFLiteral ::= String (LANGTAG | '^^' iri)?
*
* @throws IOException
* @throws RDFParseException
* @throws RDFHandlerException
*/
private Literal tryRDFLiteral(int c) throws RDFParseException, IOException, RDFHandlerException {
Literal result = null;
if (c=='\'' || c=='"') {
return rdfLiteral(c);
}
return result;
}
/**
*
* RDFLiteral ::= String (LANGTAG | '^^' iri)?
*
* @throws IOException
* @throws RDFParseException
* @throws RDFHandlerException
*/
private Literal rdfLiteral(int c) throws IOException, RDFParseException, RDFHandlerException {
Literal result = null;
string(c, buffer());
c = read();
String text = buffer.toString();
if (c == '@') {
String lang = langtag(c);
result = valueFactory.createLiteral(text, lang);
} else if (c=='^') {
c = read();
if (c != '^') {
err();
buffer.append("Invalid string literal. Expected '^^' but found '^");
buffer.appendCodePoint(c);
buffer.append("'");
fail(buffer);
}
c = read();
result = valueFactory.createLiteral(text, iri(c));
} else {
unread(c);
result = valueFactory.createLiteral(text, XMLSchema.STRING);
}
return result;
}
/**
*
* LANGTAG ::= '@' [a-zA-Z]+ ('-' [a-zA-Z0-9]+)*
*
* @throws IOException
*/
private String langtag(int c) throws RDFParseException, IOException {
if (c!='@') {
err();
buffer.append("Expected '@' but found '");
buffer.appendCodePoint(c);
buffer.append("'");
fail(buffer);
}
buffer();
c = read();
if (!inRange(c, 'a', 'z') && !inRange(c, 'A', 'Z')) {
err();
buffer.append("Language tag must start with a letter, but found '");
buffer.appendCodePoint(c);
buffer.append("'");
fail(buffer);
}
while (
inRange(c, 'a', 'z') ||
inRange(c, 'A', 'Z') ||
isDigit(c) ||
c=='-'
) {
buffer.appendCodePoint(c);
c = read();
}
unread(c);
return buffer.toString();
}
/**
*
* String ::= STRING_LITERAL_QUOTE | STRING_LITERAL_SINGLE_QUOTE | STRING_LITERAL_LONG_SINGLE_QUOTE | STRING_LITERAL_LONG_QUOTE
*
*/
private void string(int c, StringBuilder builder) throws RDFParseException, IOException {
if (c!='\'' && c!='"') {
err();
buffer.append("Expected ['] or [\"] but found [");
buffer.appendCodePoint(c);
buffer.append("'");
fail(buffer);
}
int d = read();
int e = read();
if (c=='\'') {
if (d=='\'' && e=='\'') {
string_literal_long_single_quote(c, d, e, builder);
} else {
unread(e);
unread(d);
string_literal_single_quote(c, builder);
}
} else {
if (d=='"' && e=='"') {
string_literal_long_quote(c, d, e, builder);
} else {
unread(e);
unread(d);
string_literal_quote(c, builder);
}
}
}
/**
*
* STRING_LITERAL_QUOTE ::= '"' ([^#x22#x5C#xA#xD] | ECHAR | UCHAR)* '"'
*
*
* where
*
* #x22="
* #x5C=\
* #xA=new line
* #xD=carriage return
*
*/
private void string_literal_quote(int c, StringBuilder builder) throws RDFParseException, IOException {
assertEquals('"', c);
while ( stringQuoteChar(c=read(), builder));
assertEquals('"', c);
}
protected void assertEqualsIgnoreCase(int expected, int actual) throws RDFParseException {
if (Character.toUpperCase(expected) != Character.toUpperCase(actual)) {
StringBuilder err = err();
int lower = Character.toLowerCase(expected);
int upper = Character.toUpperCase(expected);
err.append("Expected '");
err.appendCodePoint(lower);
err.append("' or '");
err.appendCodePoint(upper);
err.append("' but found '");
appendCodePoint(err, actual);
err.append("'");
fail(err);
}
}
protected void assertIgnoreCase(String expected) throws IOException, RDFParseException {
for (int i=0; i
* STRING_LITERAL_LONG_QUOTE ::= '"""' (('"' | '""')? ([^"\] | ECHAR | UCHAR))* '"""'
* * STRING_LITERAL_SINGLE_QUOTE ::= "'" ([^#x27#x5C#xA#xD] | ECHAR | UCHAR)* "'" ** * where * *
* #x27=' * #x5C=\ * #xA=new line * #xD=carriage return **/ private boolean stringSingleQuoteChar(int c, StringBuilder builder) throws RDFParseException, IOException { if (echar(c, builder) || uchar(c, builder)) { return true; } if (c!='\'' && c!='\\' && c!='\n' && c!='\r') { builder.appendCodePoint(c); return true; } return false; } private void string_literal_long_single_quote(int c, int d, int e, StringBuilder builder) throws RDFParseException, IOException { final char q = '\''; assertEquals(q, c); assertEquals(q, d); assertEquals(q, e); while ( stringLongSingleQuoteChar(c=read(), builder)); assertEquals(q, c); read(q); read(q); } /** *
* BlankNode ::= BLANK_NODE_LABEL | ANON ** @param c * @return * @throws IOException * @throws RDFParseException */ private BNode tryBlankNode(int c) throws RDFParseException, IOException { BNode bnode = null; return (bnode=blank_node_label(c)) == null ? anon(c) : bnode; } /** *
* ANON ::= '[' WS* ']' **/ private BNode anon(int c) throws IOException { if (c != '[') { return null; } c = next(); if (c != ']') { unread(c); return null; } return valueFactory.createBNode(); } /** *
* BLANK_NODE_LABEL ::= '_:' (PN_CHARS_U | [0-9]) ((PN_CHARS | '.')* PN_CHARS)? ** @throws RDFParseException */ private BNode blank_node_label(int c) throws IOException, RDFParseException { if (c != '_') { return null; } c = read(); if (c != ':') { unread(c); return null; } c = read(); if (!(pn_chars_u(c) || inRange(c, '0', '9')) ) { StringBuilder builder = err(); builder.append("Invalid initial character for BNode label: '"); builder.appendCodePoint(c); builder.append("'"); fail(builder); } StringBuilder builder = buffer(); builder.appendCodePoint(c); int last = -1; for (;;) { c = read(); if (!(pn_chars(c) || (c=='.') )) { break; } builder.appendCodePoint(c); last = c; } unread(c); if (last == '.') { unread(last); } return valueFactory.createBNode(builder.toString()); } private URI tryIri(int c) { int saveLineNumber = lineNumber; int saveColumnNo = columnNumber; try { return iri(c); } catch (Throwable oops) { lineNumber = saveLineNumber; columnNumber = saveColumnNo; } return null; } protected URI verb() throws IOException, RDFParseException, RDFHandlerException { int c = next(); if (c == 'a') { int cc = read(); if (isWhitespace(cc)) { return RDF.TYPE; } unread(cc); } return iri(c); } /** *
* subject ::= iri | BlankNode | collection ** @throws RDFHandlerException */ protected Resource subject(int c) throws RDFParseException, IOException, RDFHandlerException { Resource result = null; if (c == '_' || c=='[') { result = tryBlankNode(c); if (result == null) { fail("Invalid BNode definition"); } } else if (c == '(') { fail("TODO: Implement collection"); } else { result = iri(c); } if (result == null) { StringBuilder msg = err(); msg.append("Found '"); msg.appendCodePoint(c); msg.append("' but expected (iri | BlankNode | collection)"); fail(msg); } return result; } protected URI iri() throws RDFParseException, IOException, RDFHandlerException { return iri(read()); } /** * iri ::= IRIREF | PrefixedName * @throws RDFHandlerException */ protected URI iri(int c) throws RDFParseException, IOException, RDFHandlerException { if (c == '<') { String text = iriRef(c); return valueFactory.createURI(text); } else { return prefixedName(c); } } /** *
* PrefixedName ::= PNAME_LN | PNAME_NS * ::= (PNAME_NS PN_LOCAL) | PNAME_NS * ::= PNAME_NS PN_LOCAL? **/ protected URI prefixedName(int c) throws IOException, RDFParseException { unread(c); String prefix = pname_ns(); String localName = pn_local(); String namespace = namespaceMap.get(prefix); if (namespace == null) { fail("Namespace not defined for prefix '" + prefix + "'"); } return valueFactory.createURI(namespace + localName); } /** *
* PN_LOCAL ::= (PN_CHARS_U | ':' | [0-9] | PLX) ((PN_CHARS | '.' | ':' | PLX)* (PN_CHARS | ':' | PLX))? ** @return The string matching the PN_LOCAL rule, or an empty string if no match. */ public String pn_local() throws IOException, RDFParseException { StringBuilder builder = buffer(); int c = read(); if ( !pn_chars_u(c) && (c != ':') && !inRange(c, '0', '9') && !plx(c) ) { unread(c); } else { builder.appendCodePoint(c); int last = -1; for (;;) { c = read(); if ( !pn_chars(c) && (c != '.') && (c != ':') && !plx(c) ) { break; } builder.appendCodePoint(c); last = c; } unread(c); if (last == '.') { unread(c); } } return builder.toString(); } /** *
* PLX ::= PERCENT | PN_LOCAL_ESC ** @throws IOException * @throws RDFParseException */ protected boolean plx(int c) throws IOException, RDFParseException { return percent(c) || pn_local_esc(c); } /** *
* pn_local_esc :== '\' ('_' | '~' | '.' | '-' | '!' | '$' | '&' | "'" | '(' | ')' | '*' | '+' | ',' | ';' | '=' | '/' | '?' | '#' | '@' | '%')
*
*/
private boolean pn_local_esc(int c) throws IOException {
if (c != '\\') {
return false;
}
int next = read();
switch (next) {
case '_' :
case '~' :
case '.' :
case '-' :
case '!' :
case '$' :
case '&' :
case '\'' :
case '(' :
case ')' :
case '*' :
case '+' :
case ',' :
case ';' :
case '=' :
case '/' :
case '?' :
case '#' :
case '@' :
case '%' :
buffer.appendCodePoint(c);
buffer.appendCodePoint(next);
return true;
}
unread(next);
return false;
}
/**
* * PERCENT ::= '%' HEX HEX ** @throws IOException * @throws RDFParseException */ private boolean percent(int c) throws RDFParseException, IOException { if (c != '%') { return false; } char[] array = {hex(), hex()}; String text = new String(array); c = Integer.parseInt(text, 16); buffer.appendCodePoint(c); return true; } protected IriTemplate iriTemplate() throws RDFParseException, IOException { int c = next(); String text = iriRef(c); return new IriTemplate(text); } protected String iriRef() throws IOException, RDFParseException { skipSpace(); int c = read(); return iriRef(c); } protected String iriRef(int c) throws IOException, RDFParseException { assertEquals('<', c); StringBuilder builder = buffer(); c = read(); while (c != -1 && c!='>') { if (c == '\\') { uchar(); } else { builder.appendCodePoint(c); } c=read(); } assertEquals('>', c); return builder.toString(); } /** * Read UCHAR, assuming we have already consumed the leading backslash. * *
* UCHAR ::= '\\u' HEX HEX HEX HEX | '\\U' HEX HEX HEX HEX HEX HEX HEX HEX ** * @throws RDFParseException * @throws IOException */ private void uchar() throws RDFParseException, IOException { int c = read(); char[] array=null; if (c == 'u') { char[] tmp = {hex(), hex(), hex(), hex()}; array = tmp; } else if (c == 'U') { char[] tmp = {hex(), hex(), hex(), hex(), hex(), hex(), hex(), hex()}; array = tmp; } else { StringBuilder builder = err(); builder.append("Invalid escape sequence in IRI value. Expected (\\u HEX HEX HEX | \\U HEX HEX HEX HEX HEX HEX HEX HEX) but found: \\"); builder.appendCodePoint(c); fail(builder); } String value = new String(array); c = Integer.parseInt(value, 16); buffer.appendCodePoint(c); } protected char hex() throws IOException, RDFParseException { int c = read(); if (!inRange(c, 'a', 'f') && !inRange(c, 'A', 'F') && !inRange(c, '0', '9') ) { StringBuilder msg = err(); msg.append("Invalid HEX value. Expected [a-f] | [A-F] | [0-9] but found '"); msg.appendCodePoint(c); msg.append("'"); fail(msg); } return (char) c; } protected StringBuilder err() { buffer.setLength(0); buffer.append("Line "); buffer.append(lineNumber); if (columnNumber > 0) { buffer.append(':'); buffer.append(columnNumber-1); } buffer.append(' '); return buffer; } protected void fail(String msg) throws RDFParseException { StringBuilder builder = err(); builder.append(msg); fail(builder); } protected void fail(StringBuilder builder) throws RDFParseException { throw new RDFParseException(builder.toString()); } protected int next() throws IOException { int c = read(); while (isWhitespace(c)) { c = read(); } return c; } @Override public RDFFormat getRDFFormat() { return RDFFormat.TURTLE; } @Override public void parse(InputStream in, String baseURI) throws IOException, RDFParseException, RDFHandlerException { InputStreamReader reader = new InputStreamReader(in); parse(reader, baseURI); } protected void initParse(Reader reader, String baseURI) { if (this.reader != reader) { this.reader = new PushbackReader(reader, PUSH_BACK_SIZE); } this.baseURI = baseURI; } @Override public void parse(Reader reader, String baseURI) throws IOException, RDFParseException, RDFHandlerException { initParse(reader, baseURI); turtleDoc(); } protected int read() throws IOException { if (reader == null) { return -1; } int next = reader.read(); // System.out.println(" READ " + (char)next); if (next == -1) { reader = null; return -1; } columnNumber++; if (Character.isHighSurrogate((char) next)) { next = Character.toCodePoint((char)next, (char) reader.read()); columnNumber++; } if (next == '\n') { lineNumber++; columnNumber = 0; } return next; } protected void unread(int codePoint) throws IOException { if (codePoint != -1) { // System.out.println("UNREAD " + (char) codePoint); if (Character.isSupplementaryCodePoint(codePoint)) { final char[] surrogatePair = Character.toChars(codePoint); reader.unread(surrogatePair); columnNumber -= 2; } else { if (codePoint=='\n') { lineNumber--; columnNumber=Integer.MIN_VALUE; } else { columnNumber--; } if (reader == null) { reader = new PushbackReader(new StringReader(""), PUSH_BACK_SIZE); } reader.unread(codePoint); } } } protected boolean isWhitespace(int c) { return c==' ' || c=='\t' || c=='\r' || c=='\n'; } protected boolean tryWhitespace() throws IOException { int c = read(); if (isWhitespace(c)) { skipSpace(); return true; } unread(c); return false; } protected String tryCaseInsensitiveWord(String text) throws IOException { StringBuilder buffer = buffer(); String upper = text.toUpperCase(); for (int i=0; i